Concretism in the Language of Patients affected by Schizophrenia. An Empirical Analysis.

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!

DIPARTIMENTO DI

FILOLOGIA, LETTERATURA E LINGUISTICA

CORSO DI LAUREA IN LINGUISTICA

TESI DI LAUREA

Concretism in the Language of Patients affected by Schizophrenia

An Empirical Analysis

CANDIDATO

RELATORE

Chiara Battaglini

Chiar.ma Prof.ssa Giovanna Marotta

CORRELATORI

Chiar.mo Prof. Alessandro Lenci

Chiar.ma Prof.ssa Valentina Bambini

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Introduction

This thesis aims at analysing concretism in the language of patients affected by schizophrenia. It generates from a study of the spontaneous speech production of patients with schizophrenia particularly focused on three measures of their lexicon: concreteness, frequency and lexical richness.

Schizophrenia is a mental illness characterized by a constellation of symptoms among which delusions, hallucinations and disorganized speech are the most important ones for the diagnosis. Patients with schizophrenia have deficits in language production and comprehension that encompass all the levels of language. In the first chapter we will outline the characteristics of the illness (§1.1). We will particularly focus on language (§1.2), reviewing literature that analysed deficits at all levels, from syntax (§1.2.1) to pragmatics (§1.2.4).

In psychological literature one of the most studied features of schizophrenia is the so-called concretism, a tendency to stick to the sensory aspects of the stimuli that has been defined and assessed in different ways. In the second chapter we will provide a historical overview of the definition of the term (§2.1) and of the different methodologies carried out to assess it (§2.2). Despite the heterogeneity of definitions and methodologies, the deficits that characterize patients affected by schizophrenia can be defined as a lack of abstraction: the ability to abstract from sensorial and particular data, detecting similarities and differences, in order to categorize reality and create concepts.

Abstraction and concept formation is the topic of the third chapter that presents the issue from the classical theories (§3.1) to the contemporary ones (§3.4). In particular, two opposite theories are evaluated: the Embodiment Theory that claimed that concepts are modality-dependent and stressed the importance of sensory experience in concept formation and recalling (Barsalou, 1999) and the Supra-modal Hypothesis that, on the contrary, stated that concepts are abstract and detached from the sensory modality through which it was acquired (Handjaras et al., 2016). Both have positive and negative aspects: the Embodiment Theory is supported by neuroscience evidence that measured sensory activation in correspondence of conceptual information processing (Pulvermüller, 2005). On the contrary, the Supra-modal Hypothesis accounts for abstract concepts, a thorny problem for the Embodiment Theory that tried to explain it in various ways, such as through conceptual metaphors (Lakoff and Johnson, 1980).

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In order to assess whether concretism as defined in psychology is mirrored in linguistic concreteness we run an experiment to evaluate the level of concreteness in patients’ production. In chapter 4 we report the results of the study. We analysed the performance of 43 patients with schizophrenia as opposed to the one of 37 controls, in APACS test (Arcara and Bambini, 2016). A previous study (D’adda, 2016; Carabba, 2016) detected this correlation in Figurative Language 2, one of the APACS tests aimed at analyzing subjects’ comprehension of 15 figurative expressions (5 highly familiar idioms, 5 novel metaphors and 5 common proverbs). In this study we focused on the Interview, a test aimed at assessing subjects’ performance in engaging a conversation where the subject is asked to talk about four familiar topics: family, home, work, organization of the day. Besides concreteness, assessed through a concreteness rating administer to four independent judges with expertise in Linguistics, we evaluated other two measures of patients’ lexicon: frequency and lexical richness. To determine the frequency of the lemmas produced, we referred to the Italian corpus CoLFIS, Corpus e Lessico di Frequenza dell’Italiano Scritto (Bertinetto et al, 2005; linguistica.sns.it/CoLFIS/Home.htm). To evaluate lexical richness, we calculated the type/token ratio of patients’ and controls’ production. Significant differences between the two populations were measured only in the total type/token ratio, the type/token ratio for the Noun production and the Verb production (§4.2). The levels of concreteness and the frequency of the lemmas produced by patients and controls were comparable both in corpus and vocabulary production (§4.3).

These data are in contrast with the ones previously gathered (D’adda, 2016; Carabba, 2016) suggesting that patients’ lexicon is spared and that patients are indeed affected by abstraction deficits, but not by a deficit in abstractness. Even thought the material is not sufficient to accept a theory and dismiss the other one, the Supra-Modal Hypothesis seems to account for these results that, on the contrary, would be difficult to reconcile with the Embodiment Theory (§5).

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1 The Schizophrenic Language

Ordered thought, manifest in the beauty and wonder of language, is cool indeed. So too is the continuing effort of scientists to understand how that precious gift is lost in people with schizophrenia and maybe one day to give it back to them.

David Noonan (2014)

1.1 Schizophrenia

In 1911 the Swiss psychiatrist Eugen Bleuler published Dementia Praecox oder Gruppe der

Schizophrenien naming for the first time a mental illness he defined as characterized by the Spaltung: scission, a mental scission manifested in four dimensions: associative deficit, affective

disorders, ambivalence and autism (Forcignanò, 2016). The symptoms constellations attributable to schizophrenia had already been individuated by the German psychiatrist Emil Kraepelin who described as dementia praecox a clinical condition characterized by mental degeneration. The double label and the lack of a specific aetiology and pathogenesis of the syndrome created ambiguity and difficulties in the diagnosis. The need for valuable and fixed diagnostic tools led to the publishing of the Diagnostic and Statistical Manual of Mental Disorders in 1952, an aid 1

for psychiatrists to evaluate the symptoms described by the patients, to drive their observations and to interpret the clinical history of the patients. The incessant research sharpened the understanding of the disorder and provided psychiatrists with more sophisticated diagnostic tools. In 2013 the outcomes are gathered in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) according to which schizophrenia can be diagnosed when

The Diagnostic and Statistical Manual of Mental Disorder is used by clinicians in the United States and all over the

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world as a guide for the diagnosis and classification of mental disorders. It comprises three sections:

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Diagnostic Classification: a list of mental disorders recognized in DSM

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Diagnostic Criteria Sets: the set of symptoms that must be present and the ones that must be ruled out in order to diagnose a particular mental disorder

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Descriptive Text: information about each disorder (such as diagnostic features, subtypes, development and course, diagnostic measures, etc)

It was born primary as a source of statistical information and during World War II it was used to incorporate the outpatients. It was published for the first time in 1952, the second edition was published in 1980.

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the patient presents at least two of the symptoms that can be ascribed to three broader categories: positive, negative and cognitive symptoms:

• Positive symptoms consist of mental manifestations generally not attested in the healthy population and mainly include hallucinations, delusions, language disorders, disorganized behaviour;

• Negative symptoms refers to characteristics of healthy subjects which patients with schizophrenia do not exhibit and include diminished emotional expression, avolition (decrease in the motivation to begin and perform planned activities), alogia (poverty of speech).

• Cognitive deficits affect the patients’ cognitive abilities, both basic and complex, i.e. working memory, theory of mind, executive functions.

These signs of disturbance should persist for at least six months and should not be the effect of drug of abuse nor medication. Prime importance is given to delusions, hallucinations and disorganized speech: at least one of them must be present in order to diagnose schizophrenia, yet no single symptom is pathognomic of the disorder because schizophrenia is a heterogeneous clinical syndrome. The development of schizophrenia is heterogeneous as well but it is possible to establish the onset between the late teens and the mid-thirties with the peak age of onset in early- to mid-twenties for males and in the late-twenties for females (DSM-V: 102).

The causes of the illness are not clear but in the thirties the German scientist Franz Kallman claimed that genetic factors contribute consistently to the onset of schizophrenia (Kandel et al., 2015). Scientists have used several methods to investigate the genetic nature of the illness. One of these methods is based on the comparison of the concordance rates of illness in homozygous twins (whose DNA sequences are 100% identical) as opposed to heterozygous twins (whose DNA sequences are 50% identical). Assuming that the environment is the same for the couples, the fact that the concordance rates in homozygous twins are around 50%, while only reach 15% in heterozygous twins, suggests that genes do have a fundamental role in schizophrenia. Ça va

sans dire, factors other than the genetic ones are at play, as well. Otherwise, the concordance

rates should have been 100% in homozygous twins. Epigenetic mutations, environmental factors, random factors must have a role in converting the inherited genetic vulnerability into

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illness. Still, the genetic factor is so paramount that even the health homozygous twin or a simple sibling of a patient possess some of the neuroanatomical anomalies of the illness. There is a higher risk of illness in first-degree relatives of a patient affected by schizophrenia, 100% for homozygous twin, as opposed to second- and third-degree ones, 12,5% for third-degree relatives (see Kandel et al., 2015: 1395-1397 for an overview of the issue).

fMRI studies highlights cerebral anomalies in the brains of patients diagnosed with schizophrenia: the cortical volume is reduced in the dorsolateral prefrontal, temporal and parietal cortex. Prefrontal cortex is particularly affected by this atrophy in its dorsolateral area that is considered to be involved in activities that entail working memory (Kandel et al., 2015). Moreover, the dorsolateral prefrontal circuit is involved mainly in executive function and its dysfunction is related to impaired reasoning, inability to maintain attention and disorganized behavior (Tekin and Cummings, 2002: 650). The reduced cortex volume in temporal lobe is related to cognitive dysfunction (Kandel et al., 2005: 1398). The loss of grey matter is paralleled by a volume increase of the cerebral ventricles. The severity of this loss is evident in Figure 1 that represents the difference of grey matter loss between the healthy population and patients. During adolescence the loss of grey matter is physiological: there is a gradual diminishment of grey matter volume in the parietal, motor, supplementary and superior frontal motor cortex as a consequence of normal processes of synaptic reshaping. In adolescences affected by schizophrenia, the grey matter loss is deeper in areas of the temporal lobe, including the superior temporal gyrus.

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Figure 1

The right column shows the difference of grey matter loss between the healthy population and the patients affected by schizophrenia, identifying the extent of grey matter loss attributable to schizophrenia (Kandel et al., 2015: 1401)

Since several studies suggest that these structural abnormalities may be more extensive on the left than the right hemisphere, it is plausible to hypothesize that this atrophy contribute to some of the impairments in schizophrenics’ language function (Kuperberg and Caplan, 2003). Functional neuroimaging studies of the neural basis of language deficits in schizophrenia show that perturbation of brain activity in schizophrenia are not localized to one brain region but to networks comprising multiple regions, for instance structural equation modeling of a PET semantic processing study revealed differences between patients and controls in interactions among frontal regions, between frontal and temporal regions, and between lateral, frontal and anterior cingulate cortices (Kuperberg and Caplan, 2003).

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Schizophrenia is a debilitating mental illness which affects 0.5-1.0% of the world’s population with a male female ratio of 1.4:1 (Kandel et al., 2015: 1393). More than 5% of patients suffering from schizophrenia die by suicide and most of them have severe impairments in social relations preventing them from conducting a normal lifestyle. Enhancing the efficacy of the diagnostic tools and understanding the causes of the illness is paramount in order to find proper treatments and give to patients with schizophrenia the opportunity to live a decent life. As Rosenstein et al. (2015) suggest, scholars should devote their researches “to provide a framework for searching for biomarkers of psychosis that can inform early intervention” (Rosenstein et al., 2015: 250). A promising field of enquiry is language: children with childhood-onset schizophrenia exhibit aberrant patterns of neural activity during semantic and syntactic processing related to severity of the disorder (Borofsky et al., 2010), suggesting that language processing is abnormal at a very praecox phase of the illness.

1.2 Schizophrenia and Language

“The central paradox of schizophrenia (that the condition, apparently genetic in origin, persists in spite of a substantial fecundity disadvantage, ed.) can be resolved in the conclusion that the variation of which predisposition to schizophrenia is a part of variation that crosses the population as a whole, that is Homo sapiens-specific, and is associated with the capacity for language that defines the species” (Crow, 2000: 126). This theory of the British psychiatrist Tim Crow is interesting and tries to find a solution to the intricate puzzle of the origin of language. 2

Though this is not the focus of our thesis, it gives us the opportunity to show how deeply schizophrenia and language are intertwined and should be analyzed in parallel in the literature. Traditionally, speech disturbances have been regarded as a reflection of disorders affecting thinking rather than language. From the very first definitions of schizophrenia, language has been confined to a simple tool to investigate what is going on in patients’ brains rather than a

Tim Crow is a psychiatrist and researcher from Oxford. He is primarily interested in the causes of schizophrenia, 2

neurology and evolutionary theory. He is the Honorary Director of the Prince of Wales International Centre for Research into Schizophrenia and Depression. His main claims are that schizophrenia is a genetic anomaly and that patients are characterized by abnormalities in the lateralization of the brain. These observations led him to propose that language and schizophrenia have a common origin in the genetic event that gave rise to Homo sapiens that endowed humans with the faculty of language but exposed them to a genetic predisposition to psychosis. (Crow, 2000; Mitchell and Crow, 2005).

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phenomenon to be studied independently and in depth. Kraepeling attributed impairments in speech to “derailments and incoherence in the train of thought” (Kuperberg and Caplan, 2003), Bleuler claimed that disorders of association of thoughts are a fundamental feature of schizophrenia, reporting in his 1911 book, among the characteristic symptoms of patients with schizophrenia, examples of impaired speech as in the following quote (reported in Noonan, 2014), where the patient loses focus and slides off topic, showing one of the features of schizophrenic speech: derailment . 3

“I always liked geography. My last teacher in that subject was Professor August A. He was a man with black eyes. I also liked black eyes. There are also blue eyes and gray eyes and other sorts, too. I have heard it said that snakes have green eyes. All people have eyes.”

On the other hand, he specifies that these disorders do not lie in the language itself. Some scholars even deny the existence of a speech disorder: “there is no such thing as schizophrenic speech [..] I encountered plenty of schizophrenic thoughts” (Brown, 1972). In order to have an insight in someone’s mind you have not many tools available: one of the most valuable one is language. This led scholars to identify language disorders with speech disorders. On the other hand, it was stressed that thoughts and language are not the same and it was proposed to analyze schizophrenic language features independently: they can manifest themselves in different manners, there is no simple, one-to-one relationship between the language system and thought processes (Chaika, 1974). One patient could find him/herself unable to express him/herself through language but his/her thought processes may be intact (Kuperberg and Caplan, 2003).

Some scholars use the term thought disorders to refer to “subjective changes experienced and reported by a patient” and the term speech or language disorders to identify “observed abnormalities of spoken or written language” (Kuperberg and Caplan, 2003). Different approaches embrace different terminology and this has led to ambiguity and undifferentiated use of the terms. Another source of confusion arises due to the intricate and controversial definitions of thought and language in the first place that are the topics of philosophical heated debates. A Derailment is defined as “a pattern of spontaneous speech in which the ideas slip off the track onto another one that is 3

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first attempt to disentangle between these two phenomena have been pursued by traditional psychiatry that distinguished between content and form of thought. Content of thoughts refers to what the patient is talking about, form is the way concepts, sentences and words are put together: “how a person is talking, the fluency and accuracy of his speech, the grammatical correctness of his language” (Taylor, 1981: 4). Disorders affecting content include delusion, and can be defined as abnormalities in the competence of conventional norms and in the representation and evaluation of events in the real world. Disorders of the form of thought manifest through the “use of vague sentences that are difficult to follow, non sequitur responses to questions, through fragmented incomprehensible speech with neologisms, word approximations, and private word usage” (Kuperberg and Caplan, 2003). This distinction between form and content is blurred and a more clear distinction is needed. Thought disorders have been classified as positive (tangentiality , derailment, neologisms) and negative thought disorders (poverty of speech). 4

Positive thought disorder is also termed disorganized speech. This confusion and ambiguity prevented the analysis of schizophrenic language features as independent phenomena.

The first attempt to study speech disruption in patients with schizophrenia from a purely linguistic point of view was made by the American linguist Elaine Chaika (1974) who identified six definable characteristics of schizophrenic speech that encompass the different linguistic levels (Chaika, 1974: 275):

1. sporadic disruption in the ability to match semantic features with sound strings that is reflected in the production of gibberish and neologism; 2. preoccupation with too many of the semantic features of a word in

discourse;

3. inappropriate noting of phonological features of words in discourse;

4. production of sentences according to phonological and semantic features of previously uttered words, rather than according to a topic;

5. disruption in the ability to apply rules of syntax and discourse; 6. failure of self-monitor

Tangentiality is the tendency to reply “to a question in an oblique, tangential, or even irrelevant manner. The reply may 4

be related to the question in some distant way. Or the reply may be unrelated and seem totally irrelevant. In the past, tangentiality has been used as roughly equivalent to loose associations or derailment. The concept of tangentiality has been partially redefined so that it refers only to questions and not to transitions in spontaneous speech”.

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These characteristics are attested in recent literature that makes use of more sophisticated methods of investigation (§1.2.1). Chaika disentangled thought and speech disorders, claiming that thought and speech disorders are not necessarily the same phenomenon and quoting other scholars to support her view, such as Furth (1961) who, while recognizing a fundamental role to language in concept formation, suggests that it is not conditio sine qua non for the development of abstraction and generalization skills and Brown (1972), who notes that hallucinations can be reported in structurally normal language and that structurally abnormal language is not always representative of aberrant thinking.

Before analyzing the features of schizophrenic speech, it is important to distinguish it from other kinds of aberrant speech: as Covington et al. (2005) suggest, the errors made by patients diagnosed with schizophrenia are not comparable to speech errors and slip of the tongue present in normal speech, as the American linguist Fromkin (1975) had claimed: normal speakers make occasional errors and correct it when an error is pointed out. Patients, on the other hand, produce whole strings of errors and seem not to be aware of their mistakes (Covington et al., 2005). As opposed to aphasic patients, patients with schizophrenia present a relatively impaired verbal comprehension (Taylor, 1999: 64-68) and they manifest a language mastery and awareness well beyond that of most aphasics, as in cases where patients affected by schizophrenia jump from one topic to another led by the phonological features of the words they are uttering or when they consciously and deliberately create new words.

The features of schizophrenic speech are listed in the next section (§1.2.1), divided according to the language level affected. The deficit seems to encompass both comprehension and production, as well as all the levels of language, from phonetics to pragmatics. It is important to bear in mind that schizophrenia is an heterogeneous illness and it is possible that not all the patients present all of the following features and the extent to which language is disrupted may vary among patients. Moreover, linguistic performance assessment methods vary in the literature and this methodological inconsistency may produce different results. Consequently, the following list is aimed at representing the most common features of schizophrenic language.

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1.2.1 Phonetics and Phonology and Morphology

As far as segmental phonology is concerned, no disruption is detected, on the contrary, patients tend to fulfill the phonological rules of their language even when uttering the most unintelligible utterances. When a patient produce a neologism, the new word is consistent with the phonological patterns permitted by the language and “because they are so consistent with the stress and phonemic rules of English, one thinks the patient has actually made utterances of the language which one has failed to catch” (Chaika, 1974: 261). One of the patients from our empirical study (reported in chapter four), while talking about his family utters this sentence which is really hard to interpret but the new words he creates do not break the Italian phonological rules : 5

P#6: [..] le fattezze *quintestoliche di nuova famiglia *contolitamente <inspiration> inondata e vessata [..]

From this utterance, it is possible to see how morphology is spared, as well: the patient is creating new words according to the morphological rules. Italian adverbs are created from the feminine of the adjectives and the suffix -mente, which is the process followed by the patient in order to create the inexistent adverb contolitamente. These observations are in line with the literature that defines abnormal morphology as quite rare (Chaika, 1990; Covington et al., 2005; Perlini et al., 2012).

Patients show abnormal patterns of prosody which is characterized by flattened intonation, or aprosody (Covington, et al., 2005: 90). Stein (1993) points to abnormalities of pitch found in almost all the patients with schizophrenia studied who altered their voices by displacing speaking pitch, narrowing speaking pitch range and constricting vocal timbre. She suggests that pitch displacement is partly voluntary because when patients were given feedback about it, they gradually shifted toward normally pitched speech and she hypothesizes that this is a mechanism that helps individuals to cope with the illness. Pitch narrowing and timbre construction are considered as negative symptoms that create the appearance of lack of energy and affect but Stein reports that patients complained of an inability to express feelings, not of an absence of This is an excerpt from the translation of an interview to a patient affected by schizophrenia from our empirical study. 5

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affect. Both the production and the comprehension of intonation contours seem to be impaired, as shown by a series of studies reported in Cutting (1985: 254). Patients with schizophrenia tend to pause more frequently and longer and their speech contains more hesitation than normal speech. These features could at least in part result from difficulties at the semantic or pragmatics level so their classification as phonological impairment is not uncontroversial.

Chaika (1974) identified a tendency of patients to inappropriately note the phonetic and phonological features of words which is manifested in their tendency to produce sentences according to phonological and phonetic features of previously uttered words rather than according to a topic:

n. I had a little goldfish too like a clown. (pause, drop to low pitch, as in an aside)

o. Happy Halloween down. (pause, higher pitch)

(Chaika, 1974: 269)

The patient, after uttering n, produces o driven by the phonetic features of the word clown that rhymes with down. The individuation of a subject matter in this discourse is really hard, if not impossible. This extract of the interview with a patient is exemplar of patients’ inability to identify a topic and build his/her conversation around it.

1.2.2 Syntax

Chaika (1974) reports examples of impaired syntax, such as errors in tense and aspect marking, failure to pronominalize, as in “I gave my friend food so that my friend would not go hungry”, and general erroneous application of syntactic rules. Covington et al. state that “schizophrenia is accompanied by a reduction in syntactic complexity and an impairment in syntactic comprehension” (2005: 91).

Anyway, the attribution of these errors to the syntactic level of language is controversial. Chaika proposes that the errors are an effect of an impairment at the discourse level: patients have difficulty planning their discourse and these difficulties are mirrored in the syntactic structures and Covington et al. claim that they could result from an overall cognitive deficit,

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difficulty concentrating, or distraction. The same conclusions can be derived from the analysis carried out by Lelekov et al. (2000) who observed an impairment in syntactic comprehension and suggest that it could be due either to syntactic-specific impairment or to deficits in high cognitive functions required to process syntax. The authors opt for a middle way explanation and conclude attributing this deficit to a malfunction of a complex neural network involved in syntax processing impaired by selective lesions and by less selective dysfunctions. This view is supported by Condray et al. (2002) who state that impaired syntax comprehension may not be completely explained by compromised general cognitive ability and some specific impairments must be present, as well.

In order to analyze the neural processes involved in syntax processing and asses the nature of the impairment, Ruchsow et al. (2003) studied syntax comprehension in patients suffering from schizophrenia analyzing the event-related potentials elicited by semantic and syntactic mismatch. Their research measured a syntactic mismatch effect on the P600 ERP component , a 6

positive potential peaking at about 600 ms, only in control subjects and not in the patients. In contrast, the ELAN, a negative ERP deflection peaking at about 80 ms after the onset of syntactically incorrect word, did not differ between patients and controls. The P600 is thought to reflect the integration of syntactic and semantic information into a coherent sentence representation, while the ELAN is thought to reflect the automatic assignment of a grammatical structure to a string of words (Ruchsow et al., 2003).

These findings suggest that the impairments in syntactic comprehension derive from an impairment in higher level syntactic-semantic integration in patients with schizophrenia, while the early processes, such assigning phrase structure to string of words, is intact. This is mirrored in behavioral observations: patients produce a higher percentage of simple sentences and, in compound sentences, fewer dependent clauses that are not deeply embedded (Kuperberg and Caplan, 2003).

ERP are voltage fluctuations derived from ongoing electroencephalography that are time locked to specific sensory, 6

motor, or cognitive events (Kuperberg and Caplan, 2003:458). The ERP is a waveform containing a series of deflections appearing as positive and negative peaks, which are referred to as “components”. ERP components are characterized by polarity (positive or negative), peak latency (post stimulus-onset time at which largest amplitude is reached), and topography or scalp distribution (the pattern of amplitude across electrodes sites). Accordingly, components are traditionally named with a letter denoting the polarity and a number denoting either the peak latency value (e.g. the N400 is a negative component peaking at 400 ms), or the ordinal latency of the component (e.g. the P3 is the third positive peak in the waveform) (Bambini, 2012: 22)

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The preservation of syntax is manifested in online studies of sentence processing. One widespread online method is the so-called “click paradigm”: a short burst of noise presented during speech is usually perceived as occurring at, or near, a clause boundary when, in fact, the click might have occurred somewhere in the middle of the clause. This automatic mechanisms is thought to be due to the operation of syntactic constraints (Kuperberg and Caplan, 2003). Patients tend to perceive the click near clause boundaries to the same extent as matched controls suggesting that at least some aspects of syntactic processing are intact in schizophrenia. This observation is mirrored by behavioral observations: the syntactic structure of the “word salad” patients produce is not aberrant:

If we need soap when you can jump into a pool of water, and then when you go to buy your gasoline, my folks always thought they should get pop, but the best thing is to get motor oil.

(Andreasen, 1979: 1319)

The patient jumps from one topic to another without breaking any syntactic rule: the utterance he/she produces is perfectly grammatical.

1.2.3 Semantics

Two of the six impairments in Chaika’s paper concern semantics. The author suggests that neologisms could be the result of a mistake in assigning semantic features to phonological shapes and lists among patients’ disruptions this inability to assign the proper semantic features to existing words. This impairment leads to the phenomenon know as the “opposite speech”. Chaika reports many examples, such as using “yes” for “no”, “always” for “never”, “I do know” for “I do not know”. This phenomenon could be explained making reference to the nature of antonyms: items belonging to the same grammatical category and sharing all but one semantic feature, the distinguishing one. Failing to assign the right semantic feature, patients are likely to utter samples of opposite speech. Not only do the patients fail to assign the right semantic features, but also to select the relevant ones. In normal discourse, healthy people usually note only the semantic features that fill in the context, but patients produce utterances not according to a topic but based on the semantic features of previously uttered words. This phenomenon is

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defined as glossomania and is attributed to a failure of editing by Cohen et al. (1974), who studied patients’ speech production in colour identification tasks. When dealing with difficult expressive semantic tasks, such as identifying and describing subtle colour distinctions, healthy subjects produced descriptions as the following:

Both are salmon colored. This one, however, has more pink.

Patients affected by schizophrenia, on the other hand, went off into glossomania:

A fish swims. You call it a salmon. You cook it. You put it in a can. You open the can. You look at it in this color. Salmon fish.

The authors suggest that the patients are dealing with different concepts and ideas associated with the colour presented and they are not able to edit out the unwanted alternatives.

Rossell and David analyzed patients’ semantic processing performance in five measures and concluded that patients show deficits on all five: “they were worse than controls at giving an accurate definition of single words (definition), understanding the relationships between word pairs (implicitly: semantic priming; and explicitly: synonyms and word associations) and giving correct category information (categories)” (Rossell and David, 2006: 130). They tried to evaluate whether the deficit was due to access or storage problems. In neuropsychological research access problems are hypothesized in correspondence with “an inconsistent pattern of performance across sessions using the same items and [..] no frequency effects or semantic priming effects” and storage problems are inferred from “item-specific consistent performance across sessions, with the same information always affected” (Rossell and David, 2006: 122). According to the authors, the item-specific consistent performance, the presence of hyper-priming and effect of word frequency points to a storage deficit of semantic memory in schizophrenia.

The traditional empirical distinction between storage and access deficits may be blurred in schizophrenia and there is lack of agreement in the literature about the locus of the deficit. Some researchers have proposed that in these patients “the semantic memory store may be disorganized rather than degraded” (Kuperberg and Caplan, 2003: 450). Semantic priming tasks guide the scholars towards the same conclusion: several studies demonstrated greater priming

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effects in patients as opposed to controls and greater indirect priming effects, as well, suggesting that patients rely on an activated or disinhibited semantic associative network.

Trying to solve the puzzle, the American psychologist Gina Kuperberg and the American neurologist David Caplan reviewed studies about semantic competence in patients with schizophrenia carried out using different methodologies. A paradigm commonly used is the semantic or category fluency task that requires subjects to produce words within specific categories. During these tasks, patients produce words that are inappropriate for a given category, manifesting their inability to properly group superordinate exemplars in clusters and a tendency to produce bizarre associations. This characteristic behavior could be explained by both a disorganization of the storage of items and by deficits in selection of items in semantic memory. Moreover, patients seem to produce fewer words in a specified period than controls, but the difference vanishes and patients produce the same total number of category exemplars when given enough time. Naming tasks, administered as part of neuropsychological batteries designed for use with the aphasia syndrome, highlighted patients’ impairments in accessing lexical phonological representations from semantic memory and in planning speech production. In immediate and long-term recall tasks patients fail to use semantic information to improve recall of semantically related words and produce largely unorganized word lists at recall. This inability could be related to a disorganized semantic memory store that could lead to deficits in effective retrieval and category classification. These difficulties, though, are overcome when semantic cues are provided and, when given enough time, patients succeed in using semantic information to improve performance in these kind of tasks. These results suggest a deficit in accessing to or retrieving from the semantic system, rather than a degradation in knowledge. These observations suggest that there is no loss of semantic information in schizophrenia; rather, the problem seems to lie in accessing/retrieval and using semantic knowledge effectively.

Kuperberg et al. (2010) explains the same phenomenon with a different approach: they reject the dichotomy between storage of, and access to semantic information, “given the increasing evidence for a continuous interaction between semantic memory-based processes and combinatorial processes during the construction of higher-order meaning in healthy individuals” (Kuperberg et al., 2010: 70). In 2007, Kuperberg published a paper reviewing literature about ERP investigations on language processing in healthy individuals and suggested that this process comprises two routes: a semantic memory-based system that compares lexical

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relationships of the incoming stimuli with pre-existing information stored in the semantic memory, reflected in the modulation of the N400; a second combinatorial stream sensitive to thematic-semantic constraints. The outcomes derived from these two streams can conflict and when this occurs a P600 effect is detected reflecting a continued combinatorial analysis (Kuperberg, 2007). In 2010 Kuperberg and collegues hypothesized an imbalance between storage and access in patients and related their semantic impairments to an over-reliance on semantic associative activity at the expense of utilizing the combinatory, integrative stream of analysis. Patients are able to match incoming content words with information stored in semantic memory but they fail to override this semantic-based analysis during online sentence processing when demands for a deeper combinatorial and integrative analysis are increased. Patients seem to have difficulty at a discourse-level rather than single word-level. This hypothesis seems to be supported by studies of brain activities during semantic speech processing by patients affected by schizophrenia through ERP components. The N400, a negative component peaking at 400 ms, is thought to reflect the integration of lexico-semantic information and semantic processing in general. The amplitude of the N400 is larger (more negative) in the processing of words preceded by a context that is semantically incongruous, than the one detected in correspondence of words preceded by congruous context. This context can be a single word, a sentence stem or a whole story. The attenuation of the amplitude of the N400 to congruous relative to incongruous words is termed ‘the N400 effect’. The modulation of the N400 is thought to reflect the semantic processing of a word in relation to its preceding context, with a larger N400 amplitude reflecting an increased difficulty in semantic processing (Kuperberg et al., 2010). On-line language processing tasks gave scholars an insight on what is going on in patients’ brain. In a mediated priming paradigm an N400 congruity effect to target words that were preceded by indirectly related words (“lion” and “stripes” related to “tiger”) was reported in patients but not in controls. This result supports the idea of a disorganized organization of semantic connective network in patients showing abnormal activity spread. The abnormalities in the lexico-semantic network are revealed by the observation of an N400 effect in words preceded by semantically associated homonym when the surrounding context suggested the secondary meaning of the homonym in healthy population but not in patients. The context in patients failed to override the semantic associative effects of its individual words. Moreover, several studies reported an increased N400 latency in patients suggesting a delay in contextual integration in patients with schizophrenia.

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1.2.4 Pragmatics

Disorganized speech is one of the fundamental symptoms to diagnose schizophrenia, according to the DMS-V, and is manifested through topic switching (derailment or loose association), answering to questions in a obliquely related or completely unrelated manner (tangentiality) and speech disorganization that can lead to complete misunderstanding of the utterances produced by patients (incoherence or “word salad”). These phenomena occur primarily at the level of the whole discourse and consequently can be classified under the label of “pragmatic deficits”. Pragmatics results to be the most obviously disordered level in schizophrenia. Pragmatics is that part of linguistics that analyzes language use in context and deals with “how communicative agents’ minds brains represent and share intentions, beliefs, situations and the various components of the context in order to construct a shared meaning and to engage in successful communication” (Bambini and Bara, 2012: 1). For this purpose establishing reference and identifying real-world objects that the speaker is talking about, and keeping the reference clear without excessive repetition of words is of primary importance.

One tool to achieve this goal is producing cohesive utterances. Several studies demonstrate that cohesion is impaired in patients affected by schizophrenia. Rochester and Martin (1979), for instance, show how patients have a greater tendency to identify referents non-verbally, have troubles with presumed information and indirect references and use fewer cohesive ties.

The language production of patients is generally less informative and more tangential than normal, characterized by empty speech, filled with semantic paraphasias and by local coherence errors such us the frequent use of pronouns without antecedent, deictic terms without clear referents and frequent derailments that make their discourse vague and ambiguous (Marini et al., 2008). Moreover, schizophrenic speech is characterized by structural unclarities and wrong words, and statistical measures of type-token ratio highlighted scarce lexical density in patients who tend to repeat the same expressions. This behavior manifests patients’ inability to plan and produce a proper discourse.

Another characteristic of the deficit at the pragmatic level in patients is the incoherence of their utterances: schizophrenic speech does not hold together (Covington et al., 2005). Chaika claimed that what are absent in schizophrenic speech she reported are “the discursive markers necessary to show connections and to orient listeners to her topic” (Chaika, 1974: 268). What

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results apparent is a lack of structure in schizophrenic discourse, suggesting an impairment in discourse planning.

One of the founding theory of pragmatics is Grice’s principle of cooperation (1975). Patients do not follow the maxims producing off-topic, rambling and uncooperative answers to questions (De Decker and Van de Craen, 1987).

Another characteristic feature of schizophrenic language is the so-called concretism, that is the central topic of the next chapter. From a linguistic point of view, this feature can be defined as patients’ inability to understand non-literal meanings: proverbs, metaphor and irony are not understood by patients affected by schizophrenia as by healthy people. This is the most widely investigated feature in patients with schizophrenia and the tests involving proverbs interpretation have became a standardized method to assess language disruption in patients and has recently been labeled as a pragmatic deficit (§2.1) even thought the pragmatic nature of this impairment is not so clear-cut (§2.2.2).

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2 Concretism between Thought, Language and Cognition

This chapter is aimed at tracing the development of a term frequently associated with patients affected by schizophrenia: concretism. This term is used in the psychiatric literature in order to define the tendency of the patients to stick to the sensory aspect of stimulus that impedes them from holding and interpreting abstract connections of objects and concepts which manifests verbally in a failure to interpret non literal meaning and non verbally in the impairment of abstraction and categorization of reality. In the first part (§ 2.1) we will outline the history of the term in the psychological literature and in the second part (§2.2) we will explain how this feature has been assed in patients with schizophrenia.

A preliminary theoretical distinction is needed between “abstraction” and abstractness”. These two terms are distinct but have been and are often used indifferently creating ambiguities and misunderstandings. As proposed by the American professor of Psychology Lawrence Barsalou , there are six senses of abstraction: 1

1. Categorial knowledge. It is the abstraction from the settings in which they occur of the category to which the elements belong. Such as “abstracting the category of CHAIRS”. In different theoretical approaches (cf. §3) these categories are though of as unions of entities sharing sufficed and necessary qualities (the so-called Classical Theory) or as being the gathering of elements characterized by family resemblance (as in the Theory of Prototypes). 2. The behavioral ability to generalize across category members. The ability to summarize

the properties of the members of a certain category.

3. Summary representation. When people generalize behaviorally they describe an underlying summary representation.

4. Schematic representation. The process through which it is possible to “abstract the critical properties of a category’s exemplars and discard the irrelevant properties”.

5. Flexible representation. The summary representation can be applied flexibly to different tasks. Being abstracted form the settings in which they occur and categorized according to similarities in summary representation that are schematic, these representation are flexible.

Lawrence Barsalou is Professor of Psychology and interested in cognitive science. His field of research includes the 1

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6. Abstract concepts. It refers to the abstractness of concepts that range from concrete (referring to entities that can be experienced through the senses) to abstract (referring to entities that cannot be perceived through the senses).

(Barsalou, 2003: 1177-78)

The first five senses can be grouped under the term “abstraction” that refers to the process of abstraction from sensorial and particular data in order to create concepts and the last sense can be labelled as abstractness and it is the quality of the concepts that refer to entities that can be experienced though senses.

This differentiation must be borne in mind throughout the current dissertation because the aim of the empirical study reported in chapter four is to assess whether the impairment in the field of abstraction is mirrored in the processing and production of abstractness.

2.1 Origin and Development of the Term

Psychiatrists rely almost completely on the observation of behavior in order to comprehend and analyze subjects’ mental states and derive theories and diagnosis from this empirical observations. This is exactly what the Swiss psychiatrist Carl Gustav Jung did in defining the 2

various personality types that characterize and compose the human nature. The research aimed at defining the different psychological types that characterize humans had already been pursued by his collaborator Sigmund Freud who, at the beginning of the ‘900 identified two different kinds of thought processing in humans: a primary-process thought, characterized by a primitive form of cognition that is “irrational, autistic, free-associative, and concrete”; and a secondary-process thought which represents the “logical, reality-oriented, abstract thought” (West and Martindale, 1988: 547). Even though the paths of the two psychiatrists separated, the influence of Freud is detectable in Jung’s work. In his depiction of psychological types he defined two opposite ways of thinking and feelings that contribute in detecting to which type the subject belongs: abstraction and concretism. Abstraction is defined as the drawing out of a content from a context made up of other elements, a “mental activity that frees this content from its association with the Carl Gustav Jung (Kesswyl 1875 - Küsnacht 1961) was a Swiss psychiatrist. He was influenced by Beuler, Janet and 2

Freud. He designed a method to reveal complexes through word associations and devoted part of his work to defining personality types. (from treccani.it/enciclopedia/carl-gustav-jung)

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irrelevant elements by distinguishing it from them” (Jung, 1921: 409). On the contrary, “a concretely thought concept is one that has grown together or coalesced with other concepts”, concretistic thinking operates with concrete concepts and percepts and is constantly related to sensation, never segregated from “its sensuous context” (Jung, 1921: 420). It is defined as a primitive thought process. If characterized by concretistic thinking, the subject is subjected to the influence of the senses at the expense of his/her own psychic independence. During his years at the Burghölzli hospital, under the direction of Eugen Bleuler, Jung worked with mental ill patients, especially with the one affected by the at that time called dementia praecox. One of the tools he used to investigate and understand patients’ illness was a word-association task (Jung, 1910). This verbal task was administered in order to understand patients’ thought associations. The first to use this task was the English statistician, psychologist, explorer, inventor, meteorologist, eugenicist, sociologist Sir Francis Galton . In 1879, he published an article 3

explaining a new experimental method in order to investigate mind’s processes of thought, aimed at giving the status and dignity of science to the study of thought processes. He defined two categories of processes: a first one, where ideas present themselves by association either with an object perceived or with previous ideas; and a second process, through which these associated ideas are fixed and vivified by the attention. His “object is to show how the whole of these associated ideas, though they are for the most part exceedingly fleeting and obscure, and barely cross the threshold of our consciousness, may be seized, dragged into daylight, and recorded” (Galton, 1879: 150). Consequently, he started focusing his attention to different objects noting the thoughts that arouse in association with each object. After an amount of time, he repeated the experiment with the same objects, again noting the associations that arouse in his mind. Then, he selected a list of words to be studied statistically. With a chronograph, he wrote down how long it took to him to recollect two ideas associated with a word among the ones in the list. Analyzing the results he highlighted a delay when abstract ideas are dealt with, as if it was “very difficult to get a quick conception of the word “carriage”, because there are so many

Sir Francis Galton was born in 1822 in Birmingham. He was Charles Darwin’s cousin. He is the father of eugenics, a 3

program aimed at artificially producing a better human race through the regulation of marriage and thus procreation. Among his interests there were mathematics and statistics (he is the one who introduced the method of percentiles) and psychology. He was the first to recognize the so-called “lexical hypothesis”: salient and social personality differences are encoded into language. According to him, studying language it is possible to derive information about personality traits (Revelle, 2015).

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different kinds [..] But limit the idea to, say, a landau, and the mental association declares itself more quickly” (Galton, 1879: 154). Moreover, he observed a less variety in the mental stock than he had expected, suggesting that “the roadways of our minds are worn into very deep roots [..] the mind is perpetually traveling over familiar ways without our memory retaining any impression of its excursions” (Galton, 1879:155). He succeeded in assessing statistically and scientifically a large class of mental phenomena, giving credits to these kinds of investigations. Thanks to his study, he was able to distinguish three groups of associated ideas: a parrot-like memory, where the association is guided by an imagined sound of words; visual imagery, where every other kinds of sense-imagery are at play; and the histrionic representation, defined as a “very frequent way of generalising” (Galton, 1879:159). The last group is the basis for conceptualization, as no general idea is hold without its translation into this form that is characterized by the representation of the subject either as an actor or a spectator of an “imaginary mental theatre” and by the feeling of a sense of muscular action while witnessing “a puppet of my brain [..] perform that action, and I assume a mental attitude appropriate to the occasion” (Galton, 1879: 159). Furthermore, Galton identified three groups of associations according to the different kinds of words that could be admitted: one group with words that could be represented under some mental image, such as “abbey”, “abyss”, a second group that contained words that admitted histrionic representation, such as “abhorrence”, “ablution”, and a third group of associations characterized by the more abstract words that are the more difficult to produce and understand. The author concluded remarking precisely this difficulty to seize and manipulate abstract ideas that we grasp imperfectly “and hold on to their skirts with great difficulty” (Galton, 1879:161). Despite the lack of advanced technology and methodology, Galton’s work presents interesting hypothesis and observations and it is admirable how current some issues are, as for instance his idea of a limited working stock of ideas to which the mind recurs “in conducting its operations, therefore its tracks necessarily become more defined and its flexibility diminished as age advances” (Galton, 1879:162).

In Jung’s experiment, patients were presented with a list of words and were asked to produce the first word that came to their minds after hearing one. Reaction times and accuracy of responses were calculated and analyzed. The patterns of responses were heterogeneous but generally patients tended to manifest longer reaction times and abnormal responses. These can in turn manifest as one of the following phenomena: the production of an inappropriate word, the

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production of a definition of the word (such as: apple - a tree fruit), repetition of the stimulus word, the production of more than one word or failure of reproductions. What Jung inferred from patients’ behavior is a tendency to produce bizarre associations. These bizarre associations were interpreted in light of mental thought processes, particularly, unusual associations were related to complexes: “unconscious patterns of memories, emotions, wishes, perceptions, organized around a common theme” (Jung, 1921). By analyzing the concept associations a word elicited in the patients, Jung inferred their mental processing, attributing verbal phenomena such as hesitations, slips of the tongue, bizarre associations, to an “intellectual weakness which express itself in a tendency towards definitions which [..] does not tend towards generalization, but the content of the stimulus is defined or designated in the sense of the complex” (Jung, 1909: 110). This tendency manifests the concretistic thinking as later defined by Jung himself: “a predominance of the sensation factor in psychological orientation” (Jung, 1921: 421).

Likely, the results of these studies with word-association tasks are what led Bleuler to claim that “among the basic symptoms the disturbances of association are especially important [..] links of association following one another in sequence may lack all relation to one another so that thinking becomes disconnected” (Bleuler, 1916: 195). Inspired by Jung’s studies, Bleuler hypothesized that this feature was at the bottom of an impairment in abstraction and claimed that “the poverty of association impedes the formation of concepts [..]. The more abstract a concept the more combinations must be made. That is why there is an absence of higher abstractions. Many concepts are also falsely formed because the essential is not differentiated from the unessential” (Bleuler, 1916). Having explicitly related deficits in abstraction and patients affected by schizophrenia, thought confounding abstraction and abstractness, the term concretism is generally traced back to Bleuler, but it is unquestionable that his idea of concretistic thinking as a consequence of loosening of association is the legitimate child of a scientific marriage between the two colleagues Bleuler and Jung.

This idea of a lack of abstraction as a characteristic feature of schizophrenia is evident in the works of the American psychologist William White, who identified abnormal speech as the signal of patients’ inability to abstract and advocated a better investigation of schizophrenic language because this analysis “would inevitably lead to a full consideration of thought of which language is an expression and so to a quite complete treatment of the whole subject of psychology” (White, 1926: 396). He defined language as a mean to make intelligible to others

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the experiences of an individual that, due to their richness in details, would be incommunicable without recurring to symbols and language. Language is defined as “an abstraction in which the elements of actual individual experience are replaced by symbols “ (White, 1926:397). This kind of abstraction is not present in patients and even thought they use the same words as we do, the interpretations they attribute to them is different. Patients have mental and imagery experiences characterized by “a substantial and concrete nature”, while healthy people are capable of interpreting symbols and creating analogies (White, 1926). Many expressions are preserved, such as “collect our thoughts”, but while for healthy people these expressions are symbolic, patients understand them literally and make “gesture with similar meaning” (White, 1926: 400). This actual interpretation of symbolic expressions, according to White, leads patients to interpret as real the metaphorical idea of “being one with somebody” and could be at the basis of the patients’ mystical behavior that make them feel a sense of union with the universe and eventually think to be God. This delusional behavior is what led scholars to compare schizophrenic to primitive people and suppose a regression in schizophrenic cognitive abilities to our ancestors’ level. Another possible analogy would be the one with children: “children, like patients, love to make up a sort of neoplastic language of their own, having meanings known only to themselves or their immediate circle” (White, 1926: 402). Others features are shared among the two populations: perseveration and stereotypy in speech and actions, preference for simple melodies and rhythms. All these pieces of evidence guided the author to the conclusion that schizophrenia is a regression psychosis. But rather than primitive and children, White used the metaphor of a machine: patients are provided with a simpler machine to interpret reality. Particularly, thought processes and language, the machines human possess to interpret reality, are of a lower order of abstraction. Accordingly, White claimed that patients thought processes should develop contrary to healthy development where “thought and language [..] change from feeling, concreteness and perception in the direction of reasoning, differentiation and abstraction” (White, 1926: 412). Thus, schizophrenic language is of a lower order of abstraction and this results in the fact that “expressions we regard as figurative such as looking down or collecting our thoughts are taken literally”(White, 1926: 409).

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Another important contribution to the understanding of schizophrenia was made by the works of Lev Semyonovich Vygotsky . The Soviet psychologist was particularly interested in studying 4

children concept development and in 1934, in Thought and Language, he compared patients’ mindset with the one that characterizes children in the stage immediately precedent to conceptual thought. His idea of concepts formation echoes Piaget’s approach and is defined as a process that involves different developmental stages. He believed in a stratification of knowledge that is organized in a subordinative way in the brain: a new concept is built upon an older one. The acquisition of a new concept or of a new piece of knowledge cannot succeed unless the subordinate concept had previously been acquired. Rejecting the hypothesis of a primitive thought process, he highlighted similarities between children and patients suffering from schizophrenia, suggesting that child-patient is a better equivalence, as already suggested by the name previously attributed to Schizophrenia: dementia praecox. In his analysis of children he found that the most important development in thoughts happens when children thought process changes from complex to conceptual. In parallel, he noticed that the most important 5

deterioration in schizophrenic thought is an impairment in the formation of concepts. The child acquires the concepts by associations but he/she groups and combines referents in a different way than adults and the associations of children and concepts of adults begin to differ. When a complex and a concept refers to the same referent, the complex is called pseudoconcepts. These pseudoconcepts allow adults to understand children and healthy people to understand patients with schizophrenia: their words coincide with ours but their meaning and conceptualization differ. This phenomenon is what would explain, according to the clinical psychologist George Kassimer Yacorzynski, the patients’ performance in verbal tests aimed at assessing subjects’ vocabulary competence and that led scholars to claim that schizophrenics’ vocabulary is unaffected by general deterioration. In 1941 he published a paper about these kinds of tests arguing that what is assessed there is just the final result of a process of definition of words, while it would be important to understand which path is followed by patients to achieve the same Lev Semyonovich Vygotsky (1896-1934) was a Soviet psychologist who stressed the importance of the social context 4

in the developing of personality traits and cognitive architecture. According to him, the environment affects children mental development: in a rich and stimulating environment the child can develop abilities earlier than in a poor context (Fonzi, 2001).

Vygotsky uses the term “complex” in order to refer to a type of simple elementary generalization found in the thought 5

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results as healthy people because “the organism whose intellectual horizon has been diminished due to pathological causes would still be able to reach the same goal result, but this would be accomplished in relation to his general level of intellectual ability” (Yacorzynski, 1941: 264). This hypothesis will be proven empirically (§2.2.2).

The complexes and pseudoconcepts, according to Vygotsky, ontogenetically precede concepts and are the underlying layer of concepts. In the same way, associations are substructure in the development of higher forms of thinking. They remain covered below the layer of conceptual thinking unless a disturbance in the higher intellectual processes occurs due to the mental illness. He detected these disruptions in association with a task that required patients to form artificial concepts through the association of meaningless syllables with definite concepts. This kind of task was developed by the German psychologist Narziß Ach but he was interested in introspection investigation rather than concept formation. In his 1934 work, Thought and

Language, Vygotsky modified the task and applied his methods in order to investigate concept

formation processes. The subjects were presented with wooden blocks varying in colour, shape, height and size. Each block had a name written on the underside, hidden from the subject. The name is one of the following nonsense words: lag, applied to all tall large figures, bik, to all flat large figures, mur, on the tall small ones, and cer, on the flat small ones. The examiner selected one of the objects and read its name, asking to the subject to select all the other blocks that might belong to the same kind. When he/she made a mistake, the examiner corrected it giving the subject hints to understand to which characteristics of the blocks the nonsense word referred to and eventually to succeed in the task. This gradual introduction of the means of solution permitted the examiner to investigate the total process of concept formation in all its dynamic phases. This process can be divided in three stages, each comprising sub-phases. The first step towards concept formation is the formation of unorganized heap of unrelated objects grouped together without any basis. At this stage, the meaning of the words refers to “vague syncretic conglomeration of individual objects that have [..] coalesced into an image in his (of the child) mind” (Vygotsky, 1986: 110). The second phase is characterized by a type of thinking called thinking in complexes: objects are grouped not only according to subjective impressions but even to bonds actually existing between the objects, even thought these relations are thought of in a different way than in conceptual thinking: the bonds between objects “are concrete and factual rather than abstract and logical” (Vygotsky, 1986: 112). This stage is characterized by