Linguistic Viewpoint in the Narratives of People Diagnosed with Schizophrenia Evelien M. van Beugen
Evelien M. Van Beugen, Centre for Language Studies, Radboud University Nijmegen. Supervised by Linde van Schuppen, MA; dr. Kobie van Krieken & prof. dr. José Sanders.
Introduction
Schizophrenia is a mental disorder that is phenomenologically characterized by self-disturbance (Mishara, 2014); “an abnormality of basic or minimal self-awareness, of the normal, first-person quality of experience”, i.e., of ipseity, which is “the core sense of existing as the subject of one’s own experiences and agent of one’s own actions” (Sass, 2018, p. 720). In line with this self-disturbance, people with schizophrenia tend to have difficulties with intersubjectivity: a restricted capacity to respond to the social environment and to reach a shared understanding through adequate interaction with others (Fuchs, 2015). Problems with taking others’ perspectives might be reflected or revealed in language since linguistic interactions (e.g., writing a story, conversing) assume a common ground of knowledge and understanding between Speaker and Hearer from which the language use is coordinated, partially through the use of Theory of Mind. More specifically, narratives are a form of language interaction in which multiple perspectives (Speaker, Hearer, and Others) are continually interwoven, and one thus has to continually coordinate and switch between these various perspectives (i.e., ToM) and must be able to conceive things from other points of view (i.e., intersubjectivity) (Verhagen 2005; Verhagen, 2007). The failure to successfully coordinate these perspectives, and hence the embedded representations of self and others, are theorized to become detectable in language if disturbances in self-experience are present, which is the case in schizophrenia (Mishara, 2014; Sass & Pienkos, 2015).
In language, perspectives, or viewpoint can be expressed on the morphological, syntactic, lexical and discourse level. In the current study we will focus on the expressions of perspective at the lexical level: epistemic markers, evidential markers, personal pronouns and backward causal connectives. We will identify and quantify these markers, in order to discover more about the role of perspective and intersubjectivity in the language use of people who have a schizophrenia diagnosis. More specifically, this paper will shed light on whether it is the case,
and if so, how the language of schizophrenia patients is to be characterized as atypical in terms of perspective and what their language use can tell us about the nature of potential anomalies in their cognitive perspective-taking abilities.
Theoretical Background
Schizophrenia and (inter)subjectivity Schizophrenia as a self-disorder
Schizophrenia is a mental disorder characterized by a disruption in the processes that form an interactive relationship between the self and other(s), which results in a collapse of self-experience (Mishara, 2014). This self-disorder entails a disruption of a person’s sense of minimal self; a sense of self that refers to the minimal requirements for selfhood, the subjective character (Zahavi, 2008) which is intrinsic to any phenomenally conscious state (Zahavi, 2014). Therefore, it is impossible to have any kind of experience without simultaneously being conscious of that experience and the fact that it belongs to us: ‘a sense of mineness’, which is inherent to any form of consciousness (Zahavi, 2014). Hence, the self is a subject of experience.
Another form of selfhood, besides the minimal self, is the narrative self (Zahavi, 2008).1 The narrative self is the product of a narratively structured life: the stories that we tell about ourselves and that are shaped through our relations with other people (Zahavi, 2008). For example, stories about personal challenges or hopes for the future are important to develop the narrative self (Lysaker et al., 2010). Because the minimal self entails a minimal level of self-awareness it is a prerequisite for the emergence of a narrative self (Bortolan, 2020). Therefore, it could be argued that a disruption in the minimal self could pass through to our narrative self (Bortolan, 2020).
1 Both the minimal self and the narrative self are two forms of selfhood that complement each other (Bortolan,
Schizophrenia and intersubjectivity
In line with the disruption of self, is a disruption of intersubjectivity in patients with schizophrenia. Intersubjectivity entails the relationship between the self and the Other(s); there is a bridge between the personal and the shared; the world is not only available to oneself (Ammaniti & Gallese, 2014). These difficulties with intersubjectivity are apparent in that people with schizophrenia tend to show a restricted capacity to respond to the social environment and to reach a shared understanding through adequate interaction with others (Fuchs, 2015). This can be argued to result in problems with perspective-taking.
More specifically, people with schizophrenia experience problems distinguishing between their own mind and between the mind of others in addition to experiencing devitalization, i.e., the sense that others seem dehumanized or do not have minds (Pérez-Álvarez, García- Montes, Vallina-Fernández & Perona-Garcelán, 2016). Studies also show that people with a schizophrenia diagnosis experience difficulty with Theory of Mind (ToM) (Bora, Yucel & Pantelis, 2009; Corcoran, Mercer & Firth, 1995; Sprong, Schothorst, Vos, Hox & van Engeland, 2007; Brüne, 2005). Theory of Mind entails the ability to understand and take into account another individual’s mental state (Premack & Woodruff, 1978); the ability to theorize about the minds of others and the awareness that others have different perspectives (Zeman, 2016). Taking this into account, coordinating the perspectives of Speaker, Hearer (and Other), and hence the embedded representations of self and others might be challenging for people with a schizophrenia diagnosis since they experience disturbances in self-experience (Mishara, 2014).
Lexical (inter)subjectivity in language
Viewpoint in language / Subjectivity and intersubjectivity
In and through language we constitute ourselves as the subject (i.e., I) (Beneviste, 1971). This subject and, inherently, our perspective, are necessary to enable communication:
“language is possible only because each speaker sets herself up as a subject by referring to herself as I in the discourse” (Beneviste, 1971). Because of this, I will be another person when the Hearer says I than when the Speaker says I. Similarly, Kärkkäinen (2006, p. 702) says that subjectivity refers “to the phenomenon that the speaker with her attitudes and beliefs is present in the utterances that she produces.” We express subjectivity and perspectivization through, for example, saying I or by describing events or state of affairs from a particular perspective, that of our own. What perspectivization and subjectivity have in common is that they both involve a subject of conceptualization (Verhagen, 2007), i.e., a ‘viewer’ or the Speaker in a discourse. Intersubjectivity enables us to coordinate and switch between the multiple perspectives that are present in linguistic interaction (e.g., writing a story, conversing) and enables us to conceive of things from other points of view (Verhagen, 2005; Verhagen, 2007). Intersubjectivity and subjectivity go hand in hand in linguistic interaction, since linguistic interaction does not just involve a personal or individual matter (i.e., the speaker commenting or stating facts about the world), it also involves interpersonal matters; reasoning or voicing an opinion means to elicit a response of solidarity from the addressee (Hunston & Thompson, 2000).
Viewpoint devices / lexical viewpoint
In language, perspective, or viewpoint, can be expressed on the morphological, syntactic, lexical and discourse level. In the current study we will focus on the lexical level. By using certain words, we can express perspective, or viewpoint, as shown in Example 1 (adopted from Nuyts, 2001, p.128).
1)
a) I think/believe they have run out of fuel. b) Who says so?*
The way in which one can object to a speaker’s epistemic qualification of a state of affairs is made clear in the example above, that is, the use of the mental state predicate, I think, leaves no doubt about who is responsible for the epistemic evaluation and, therefore, the reaction of the Hearer in 1b is impossible and 1c possible (Nuyts, 2001). Because of this, predicates such as I think, have a (inter)subjective nature (Nuyts, 2001) and as we will discuss in the next section, are (inter)subjective linguistic viewpoint markers.
We, speakers, use certain words like in Example 1 in intersubjective discourse. These words, or linguistic viewpoint markers, require the Speaker to coordinate the multiple perspectives (Speaker, Hearer, and Others) that can be present in linguistic interactions and, thus, require some skill of intersubjectivity. In the current paper we will investigate various types of perspective markers in order to discover more about the role of perspective and intersubjectivity in the language use of people who have a schizophrenia diagnosis. We will investigate, firstly, whether and how these linguistic viewpoint markers in narratives of people with a schizophrenia diagnosis differ from those in narratives of neurotypical people. Furthermore, we will elucidate if and how the language of people with schizophrenia is to be characterized as atypical in terms of perspective and what their language use can tell us about the nature of potential anomalies in their cognitive perspective-taking abilities.
Linguistic viewpoint makers: quantifying (inter)subjectivity
Epistemic markers
Epistemic modality is a sub-type of linguistic modality with which a speaker can communicate doubt, certainties and guesses; the speaker can communicate his/her “qualitative judgment of a proposition” (Velupillai, 2012, p. 219). Another definition, posed by Nuyts (2001) is that epistemic modality is concerned with the estimation of the likelihood that (some aspect of) a certain state of affairs is/will be/has been true (or false) under the consideration of the context
of our world (Nuyts, 2001). This likelihood is situated on a scale (henceforth, ‘epistemic scale’), going from certainty to uncertainty; which can be reflected in language with different epistemic modality markers (Nuyts, 2001).
Epistemic markers in West European languages (i.e., Germanic and Romance languages) can take the form of modal auxiliary verbs such as can, could, shall, might and may; modal adverbs and adjectives such as possibly, likely, slightly, maybe and perhaps; longer constructions such as be able to, that is necessary for X to, could have been and it is possible that (Nuyts, 2001); and Complement-Taking Mental Predicates (CTMPs) such as I think, I believe, I hope, I expect, I know and I doubt (Van Bogaer, 2011; Nuyts, 2001).
Incidentally, epistemic modality, or epistemic stance, also encompasses the expression of internal psychological states of the individual speaker; manifesting subjectivity (Kärkkäinen, 2006; Verhagen, 2005). They also express intersubjectivity, since participants in a discourse display an orientation toward reaching a common understanding and a shared stance, i.e., participants in a discourse try to reach a mutual stance towards a matter (see Kärkkäinen, 2006 for extensive examples). More specifically, in the case of Complement-taking Mental Predicates (CTMPs) (Degand & Simon-Vandenbergen, 2011), the Speaker can voice a personal opinion (subjectivity) which may be wrong and, therefore, the Speaker leaves room for other opinions or a reaction of the Hearer (Nuyts, 2011). The speaker, thereby, takes the perspective of the hearer into account; expressing intersubjectivity. A CTMP like ‘I think’ can also be seen as a sort of prototype of subjective language since it contains a reference to the speaker (the first-person pronoun) and a verb that denotes a private or interior cognitive process (Kärkkäinen, 2006), expressing subjectivity.
A subtype of epistemic modality markers, that Nuyts (2001) does not include in his selection of epistemic modality markers, are expectation markers such as actually and indeed. They mark a mismatch between what A says and what A expects B to say. These markers
concern the common ground (i.e., the knowledge that is shared between the discourse participants at the moment of conversation) since a contrast is marked by the speaker between the addressee's model and the speaker’s discourse model (Nuyts, 2001).
By using an epistemic modality marker, the speaker can incorporate the addressee’s discourse model into her own. By using an epistemic modality marker Theory of Mind is involved on the part of the speaker, in that it presupposes a number of implicit assumptions about the state of mind of the hearer: the speaker takes the perspective of the hearer into account by using a marker as actually or indeed (van Bergen, van Gijn, Hogeweg & Lestrade, 2011), which expresses (inter)subjectivity. As shown in Example 2b, inderdaad (indeed) marks a confirmation of the hearer’s beliefs state, given the speaker’s estimation of the hearer’s belief state, whereas actually (eigenlijk) (Example 2c) marks a proposition unexpected to the hearer, also given the speaker’s estimation of the hearer’s belief state (van Bergen, van Gijn, Hogeweg & Lestrade, 2011).
2) a. Het was vast prachtig weer in Griekenland? The weather must have been great in Greece?
b. We hebben inderdaad alleen maar zon gehad. We have (indeed) had nothing but sun.
c. We hebben eigenlijk alleen maar regen gehad. We have (actually) had nothing but rain.
Empirical evidence investigating the use of epistemic modality markers in people with a schizophrenia diagnosis is, to the best of our knowledge, lacking. However, since autism spectrum disorder (ASD) and schizophrenia are related in the sense that people with ASD or
schizophrenia can both experience difficulties with ToM (Bora, Yucel & Pantelis, 2009; Corcoran, Mercer & Firth, 1995; Brüne, 2005; de Mulder & Gautero-Watzema, 2018; Baron-Cohen, 2000), it is worth looking into a study by de Mulder and Gautero-Watzema (2018). They investigated the acquisition of epistemic modal auxiliaries in typically developing (TD) children and children with an autism diagnosis (ASD) and the role that ToM plays in acquiring these epistemic modal auxiliaries, since children with ASD can experience difficulties with ToM, as mentioned above. Their study shows that children that pass a series of ToM tests perform significantly better than children that did not pass the tests on epistemic modal auxiliary understanding. Their results seem to suggest a relationship between ToM skills and lexical epistemic modal understanding. Since people with schizophrenia can experience ToM difficulties, it might be the case that people diagnosed with schizophrenia also have difficulties with lexical epistemic modal markers. Similarly, these difficulties could also show with other epistemic modality markers, such as modal adverbs and CTMPs, since they also refer to positions on the epistemic scale as they are also concerned with the likelihood that a state of affairs is/will be/has been true (Nuyts, 2001).
Based on the literature we discussed above and the empirical findings we presented, we expect that people with a schizophrenia diagnosis will make less use of epistemic modality markers compared to compared to a benchmark corpus comprised of neurotypical narratives, because epistemic modality markers express (inter)subjectivity, which people with schizophrenia can experience difficulty with (Fuchs, 2015). When losing the connection with others, self and world, the expression of doubt, i.e. questioning one’s knowledge (Nuyts, 2001), is hypothesized to decrease as is also corroborated by the rigidity of psychotic delusions (American Psychiatric Association, 2013; Kiran & Chaudhury, 2009). That is, if one believes that the world is only available to oneself, it is unnecessary to try to reach a mutual stance or understanding towards a matter, since other’s perspectives, beliefs and understanding do not
matter. Therefore, we expect lower frequencies of epistemic modality markers in the narratives of people diagnosed by schizophrenia compared to a benchmark corpus comprised of neurotypical narratives.
Evidential markers
How people talk about the status of their knowledge, their epistemological assessment of information, can be voiced or expressed by evidential markers. In Dutch this is expressed through lexical means, for example adjectives or adverbs such as apparently (blijkbaar, kennelijk, schijnbaar) and (it) seems/seeming (zo te zien, lijken, and schijnen), and perception verbs such as to see (zien), to hear (horen), to feel (voelen), to smell (ruiken) and to taste (proeven) (Ünal & Papafragou, 2020). These markers encode information about the way in which knowledge was acquired and the subsequent relationship between speakers and their knowledge of what they talk about (Ozturk & Papafragou, 2016). In addition, they may encode the effect that this has on the assessment of knowledge as true or reliable by both speakers and their audience. A prerequisite of using evidential markers is being able to make distinctions about the sort of evidence that leads one to believe something (Papafragou, Li, Choi & Hand, 2007; Ozturk, Papafragou, 2016). Source monitoring, i.e., the ability to monitor the origin of one’s belief, is, in turn, a prerequisite in order to mark a source distinction (Papafragou, Li, Choi & Hand, 2007; Ozturk & Papafragou, 2016; Ünal & Papafragou, 2020). Reasoning about the type of evidence that leads us to believe something and knowing what event led us to believe something plays a vital role in belief evaluation and change (Ünal & Papafragou, 2020). Source monitoring builds on the understanding that people have different and variable informational relationships with the world; beliefs may change and be adjusted or updated as new information or evidence becomes available (Papafragou, Li, Choi & Hand, 2007). The phenomenon of source monitoring is part of Theory of Mind in that you have the ability to know that others have other mental states, or in this case, relationships with the world, and
reason from these mental states in order to explain and predict behavior (Papafragou, Li, Choi & Hand, 2007).
Various studies have investigated the phenomenon of source monitoring in relation to schizophrenia and found that patients with schizophrenia make significantly more errors of in the source attribution of the recognized target items than healthy controls (Moritz, Steffen, Woodward & Ruff, 2003; Brébion et al., 2000; Keefe, Arnold, Bayen & Harvey, 1999). The neurocognitive models of schizophrenia that underlie these studies are based on the idea that the psychotic symptoms in patients emerge from a difficulty distinguishing between the origin of stimuli that are internal versus external, i.e., endogenous or exogenous stimuli (Nelson, Whitford, Lavoie & Sass; 2014). The source monitoring deficits that are observed in patients with schizophrenia could arise from failures in the neural mechanisms underlying the ability to distinguish between endogenous and exogenous stimuli. These neurocognitive deficits or dysfunctions could present on a phenomenological level by the disturbed basic selfhood that is theorized to underlie schizophrenia (Taylor, 2011), as mentioned above. The difficulty patients can experience with source monitoring could result in thoughts to take an object-like quality, i.e., thoughts are experienced as if they were external objects and at the same time external objects or people can come to seem internal or dreamlike (Nelson et al., 2014). These experiences, which are hypothesized to be driven by neurocognitive disturbances, may underlie other psychotic symptoms such as auditory hallucinations (Sass & Parnas, 2003).
Based on the literature we discussed above and the empirical findings we presented, we expect to find less evidential markers in the narratives of people diagnosed with schizophrenia compared to the neurotypical narratives, because source monitoring influences ToM, in that source monitoring is needed to judge intentions and deceptions (Bright-Paul, Jarrold & Wright, 2008). People with schizophrenia can experience difficulties with source monitoring (Taylor, 2011; Nelson et al., 2014) and ToM (Fuchs, 2015). What is more, when the relationship
between one’s own mind or mental state and the world is disturbed (i.e., self-demarcation) (Henriksen & Parnas, 2012), providing the Hearer or Others in a discourse with the status of one’s knowledge, i.e., their epistemological assessment of information, is hypothesized to decrease, which is corroborated by the delusions people with schizophrenia can experience (Kiran & Chaudhury, 2009). That is, if one experiences that the world is only available to oneself, it is unnecessary to express the status of one’s knowledge, since there is no doubt about one’s epistemological assessment of information, which can be expressed through evidential markers. Therefore, we expect lower frequencies of evidential markers in the narratives of people diagnosed by schizophrenia compared to a benchmark corpus comprised of neurotypical narratives.
Personal Pronouns
The third group of markers we will investigate are the personal pronouns (e.g., I, you, he, she, them, me, her). Personal pronouns are words that can be used to refer to something or someone instead of the proper name. For example, in Example 3b, she refers to the woman in 3a and he in 3d refers to the man in Example 3c.
3) a. The woman is reading a book.
b. She is reading a book by Jane Austen. c. I saw the man sitting by the window. d. He was reading a book by Jane Austen.
Factors such as sense of self and of others, the capacity or ability for decentration and for joint attention play important roles in the use of personal pronouns: one needs to be able to understand others and other people’s minds (ToM) (Richard, Girouard, Decarie, 1999). One
has to correctly represent the listener’s understanding of the discourse topic in order to provide information that is needed to identify the pronoun’s referent (Corcoran, Mercer & Firth 1995): who does she refer to? This ability is even more important in narratives: the Speaker has to build a representation of the listener’s mental states and monitor it continually (Lorusso et al., 2007). If one experiences difficulties in representing the mind of others the use of the pronoun might be wrong, i.e., the pronoun does not refer to the right referent.
Empirical studies investigating the use of personal pronouns and schizophrenia show that people with schizophrenia use especially first-person pronouns more frequently than neurotypical controls (Fineberg et al. 2016; Junghaenel et al. 2008; Strous et al. 2009; Bedi et al. 2015; Buck & Penn, 2015; Hong et al. 2015; Minor et al. 2015). An explanation for the finding of increased use of first-person pronouns by Strous et al. (2009) is that because people with a schizophrenia diagnosis can experience a disconnection with reality and can therefore experience difficulties representing the identities of people and objects, the over-representation of the first-person pronoun can be seen as an attempt to focus more on oneself and thereby also introduce less information of others (i.e., people, objects, and places). In contrast, a study by Deutsch-Link (2016) shows the opposite; people diagnosed with schizophrenia use less ‘I’ than (healthy) controls. They explain this finding by saying that people diagnosed with schizophrenia frequently experience auditory hallucinations, such as hearing voices; instead of saying ‘I went to the park.’ they might say ‘The voices ordered me to go to the park.’ Another explanation they provide is that patients with severe symptoms might have been locked inside wards which can contribute to a reduced sense of agency and, therefore, a reduced use of the first-person pronoun (Deutsch-Link, 2016, p. 49).
Studies investigating the use of second- and third-person personal pronouns in schizophrenia show a hybrid picture: the personal pronoun ‘you’ is more often used by people who developed schizophrenia at a later time compared to participants who did not (Watson et
al., 2012), whereas, Buck et al. (2015) found that lower social cognition measures, which are theorized to be characteristic of schizophrenia (Brüne, 2005; Langdon and Ward, 2009), were significantly correlated with less second-person pronoun use, as well as the overall use of pronouns.
Based on the literature we discussed above and the ambivalent empirical findings we presented, we expect that people with a schizophrenia diagnosis will make more use of first-person first-personal pronouns, and less use of second- and third-first-person first-personal pronouns compared to a benchmark corpus comprised of neurotypical narratives. As mentioned before, schizophrenia is characterized as a self-disorder (Mishara, 2014) and factors such as sense of self and of others play important roles in the use of personal pronouns. That is, one needs to be able to understand others and other people’s minds (i.e., ToM) (Richard, Girouard, Decarie, 1999) in order to successfully use personal pronouns in a discourse. Because people with schizophrenia can experience a disrupted sense of self and therefore, also a disrupted relationship with others, we hypothesize it might be hard for them to take the perspective of the Hearer into account, that is, they will use less second-and third person personal pronouns. The use of first-person personal pronouns, however, is hypothesized to increase, as one experiences the world to be only available to oneself, it could be argued we refer to ourselves more.
Causal connectives
The last group of markers we will investigate are backward causal connectives. Backward causal connectives mark a causal relationship between events in the world and can express objectivity (e.g., doordat, zodat, daardoor) or subjectivity (e.g., want, dus) or are volitional in the case of omdat (because) (Sanders, Sanders & Sweetser, 2012). For example, when using a causal connective like daardoor or doordat the speaker is not involved in the construction of the causal relations between the events: there is no Subject of Consciousness.
On the other hand, when using a causal connective like dus or want the speaker construes a relationship in which he/she is implicitly expressed. For example, Example 4a (Sanders, Sanders & Sweetser, 2012) shows that the Subject of Consciousness is often identical to the Speaker: the relation is construed by the Speaker even though she is not mentioned explicitly, that is, in Example 4b we see that the Subject of Consciousness of 4a is explicitly expressed. When using a causal connective such as want in Dutch in Example 4c, the Subject of Consciousness, I, is implicitly expressed, such as is also the case for the English translation in Example 4a.
4) a. The neighbors are not at home, since their lights are out.
b. The neighbors are not at home, since I observe their lights are out. c. De buren zijn niet thuis, want hun licht is uit.
As shown in Example 5 (adopted from Sanders, Sanders & Sweetser, 2012), omdat is a volitional backward causal connective, because the subject, Jan, undertakes a volitional action (i.e, went swimming) for a reason, for example, in order to prevent getting too hot (Sanders, Sanders & Sweetser, 2012). By using a volitional backward causal connective, such as omdat the Speaker expresses that Jan, the subject, is responsible for this causal connection (Sanders, Sanders & Sweetser, 2012).
5) a. Jan ging zwemmen, omdat het een warme dag was. b. Jan went swimming, because it was a hot day.
We expect to find less subjective and volitional backward causal connectives and more objective causal connectives in the language of people with a schizophrenia diagnosis. Given the phenomenon of self-disturbance that people with schizophrenia can experience,
devitalization, which is the feeling or experience that the world loses familiarity and context, can arise: a feeling as though one and Others are not human beings, or only apparently so (Pérez-Álvarez, García-Montes, Vallina-Fernández & Perona-Garcelán, 2016). Because of this devitalization, expressing or marking one’s own mind or subject of conceptualization is unnecessary, since Others are not real or do not have minds: why would I mark my own perspective and, therefore, take the perspective of the Hearer into account, when the Hearer is not perceived as ‘minded’? Furthermore, since people diagnosed with schizophrenia have described their subjectivity as 'dissolving' or melting together with others or the world, like in a (waking) dream, we expect to find that their linguistic construal contains less subjective backward causal connectives and more objective backward causal connectives (Mishara, 2014; Sass & Pienkos, 2015; Sass, 1994).
Method
In the current paper we will identify and quantify the four groups of markers mentioned above, epistemic modality markers, evidential markers, personal pronouns and backward causal connectives to discover more about the role of perspective and intersubjectivity in the language use of people who have a schizophrenia diagnosis.
Participants
Twenty-six participants between 26 and 57 years old participated in this study (Mage = 52 years, SDage = 11.55). All participants indicated they had been diagnosed with schizophrenia. A letter has been sent to all treatment providers to contact us if the diagnosis was not correct. Almost all treatment providers have confirmed the diagnosis of their patients; we are awaiting several confirmations. Three participants were excluded because one participant’s diagnosis was denied by the treatment provider, one participant did not have a treatment provider to confirm the diagnosis, and another participant’s interview was repeatedly
interrupted by the partner talking. Therefore, the resulting sample consisted out twenty-three participants study (Mage = 50 years, SDage = 11.93). The average number of words of all transcripts of this corpus was 8,414 (SD = 5,183), the shortest transcript was 2,208 words and the longest transcription was 22,268 words. The corpus comprised a total of 193,525 words. Participants were recruited in several ways. Some participants contacted Linde van Schuppen (the main researcher) in response to a call on a closed forum for people with a schizophrenia diagnosis, others were brought into contact through a mutual friend of the main researcher, others participants expressed interest in taking part as a result of a public talk or publication by the main researcher, whilst others were recruited through the employee of a housing organization for protected living or via a call by a patient organization. The recruitment of participants was in line with a research protocol that was waived from being assessed under the Medical Research Involving Human Subjects Act (Wet Medisch-Wetenschappelijk Onderzoek met Mensen/WMO) by the Committee on Research Involving Human Subjects (Commissie Mensgebonden Onderzoek/CMO of region Arnhem-Nijmegen (file nr. 2017-4007). In addition, the protocol was ethically approved by the Ethics Assessment Committee for the Humanities of Radboud University (file nr. 3625). Participants provided informed consent. All participants were native speakers of Dutch and lived in the Netherlands. Participants were interviewed at home, except for two. Some participants lived independently; others had several housemates as arranged by a regional institute for protected living arrangements. None of the participants were admitted in a mental health institution at the time of the interview.
Procedure
Participants were given an information brochure about the study and gave informed consent after which the interview started. At the end of the session participants were requested to retell the narrative of the ‘Pear Film’ (see Chafe, 1980) which is part of a larger study and
not relevant for the current study (van Schuppen, van Krieken & Sanders, 2019). Participants were compensated for their participation with a gift card (€ 20). The interviews were meant to stimulate narrative language production in the participant, resulting in stretches of interactive discourse. The interviews were conducted according to the clean language method (Lawley & Tompkins, 2000); aiming to have as little interference by the interviewer on the interviewee’s verbal production by evading interpretive and morally loaded content words like ‘problem’, ‘normal’ and ‘false’ and asking for clarification without offering an interpretation. Questions were asked like ‘What happened next?’ and ‘Can you tell me more about that?’. The interview was initiated with the question ‘Could you tell me something about your life, up until now?’. Other themes that were touched upon were: the daily/weekly routine of the interviewee, relationships with other people and thoughts about the future. Other questions asked that were used to generate more response if the participant did not answer to the main themes in a narrative way, were narrative prompting questions like ‘Can you tell me something about a memory that is important to you?’, ‘Can you tell me something about what your childhood was like?’ and ‘Can you tell me something about a time in your life when you learned a lot?’. The interviews were conducted by Linde van Schuppen (main researcher). For some of the interviews the author (Evelien van Beugen) was also present and/or a third person (e.g., partner).
The interviews were recorded, transcribed by hand and anonymized. The interviews were transcribed by the main researcher, author and five student-assistants, all not trained in any specific transcription format (e.g., CHAT). Each interview was transcribed verbatim by one of the transcribers, who listened to each interview until the entire interview was transcribed. Utterances or portions of utterances that could not be fully transcribed after multiple times listening were marked as unintelligible with the convention ‘(onverstaanbaar)’ in Dutch. Other conventions used were (i) putting the utterance or word between square
brackets if the transcriber was not sure about the transcription, (ii) mark all names, places and other personal information in yellow in order to replace it later with a pseudonym, (iii) mark nonwords or dialect green in order to replace it with Standard Dutch later and (iiii) extralinguistic information were marked with curly brackets. A consensus procedure to check reliability of the transcripts was used. No coding conventions were used to mark syntactic errors, or extract word type and token variables. Both the audio and the transcriptions were saved anonymously on a secure university server for analysis. Before analyzing the transcripts, the utterances of the interviewer were taken out after which only the utterances of the interviewee remained. Lastly, all tags and extralinguistic information were removed.
CGN corpus
The neurotypical interviews were gathered from the Spoken Dutch Corpus (i.e., CGN) in 1990 (Oostdijk, 2000). We used the semi-structured interviews with teachers (i.e., component b) as a benchmark (N = 79, Mage = 64 years, SDage = 10.26) to compare with our schizophrenic corpus as a reference for neurotypical language use. The average number of words of all transcripts of this corpus was 2,879 words (SD = 491), the shortest transcript was 1,093 words and the longest transcription of 4,198 words. The corpus comprised a total of 227,464 words. All participants were native speakers of Dutch and lived in the Netherlands. Each interview lasted for approximately fifteen minutes. Since the interviews with teachers were shorter compared to our own corpus, we included all interviews with teachers to compensate for the smaller amount of data compared to our own database. One participant from the CGN was excluded because the participant was a student and not a teacher. The neurotypical narratives from the CGN were transcribed2 according to the protocol of Goedertier, Goddijn and Martens (2000). Speakers were tagged and the interviewer was
removed from the transcriptions. A list of the markers we investigated can be seen in Appendix A.
We examined how comparable the CGN and SZ corpus were. We found there was a significant difference between the ages of both corpora, Chi2(1) = 17.462, p < 0.01, with a mean age of 63.48 for the CGN and 50 for the SZ corpus. We also checked whether both databases had a similar distribution of men and women. Figure 1 represents the number of women and men in each corpus. We found there was no significant difference between the amount of men and women between both corpora, Chi2(1) = 0.272, p = 0.602.
We also looked at whether there was a difference in the place of residence of participants in both datasets. We adopted the system that was used for the CGN, namely a system with abbreviations denoting different provinces and regions in the Netherlands (see Appendix B). Every participant in both datasets received an abbreviation for their place of residence. We then looked at whether there was a difference between both corpora regarding the places of residencies and found that there was a significant difference between the two datasets, Chi2(15) = 14.32, p < 0.001. Figure 1 represents the places of residencies of the participants of both datasets.
Figure 1. Bar plot showing the number of participants living in a certain area (y-axis) for each corpus (CGN vs. SZ) (x-axis). Every bar represents a different province or area in the Netherlands (see Appendix B). We found there was a significant difference between the CGN and SZ-dataset, Chi2(15) = 14.32, p < 0.001.
Results
The current study aimed to investigate the role of perspective and intersubjectivity in the language use of people who have a schizophrenia diagnosis. The results consist of three parts. We first tested whether there was a difference in the overall percentage (inter)subjective markers used between the two corpora we investigated, the CGN and our own data (i.e., SZ-data). We then investigated whether there was a difference between the two corpora for each separate group of markers. In the last part, we further investigated our data by looking at the epistemic modality makers and evidential markers in more detail to see which markers specifically in these two groups differed the most between the two databases.
Analysis 1: All subjectivity markers
To see whether linguistic viewpoint markers in narratives of people with a schizophrenia diagnosis differed from those in narratives of neurotypical people, we tested whether the CGN-data were significantly different from our SZ-data regarding the overall percentage of (inter)subjectivity markers used in each database. We included twelve subcategories of markers in this analysis (as per the marker list in Appendix A) that express (inter)subjectivity: CTMPs, epistemic modal verbs, epistemic modal discourse particles, evidential modal discourse particles, perception verbs, evidential modal verbs and volitional verbs, subjective backward causal connectives and the volitional backward causal connectives, first person personal pronouns, second person personal pronouns, and the third person personal pronouns. The objective backward causal connectives were not included in this analysis because they do not (necessarily) express (inter)subjectivity. An overview of the total percentage markers for each corpus per marker category and marker subcategory can be seen in Table 1.
Table 1
Total average percentage markers per marker category and marker subcategory for the CGN corpus and the schizophrenic corpus.
SZ CGN
Epistemic markers 6.274 5.891
Evidential markers 0.628 0.479
Personal pronouns 0.786 0.746
Causal connectives 5.091 3.547
Epistemic modal verbs 0.693 0.719
Epistemic modal discourse particles 4.729 4.566
Evidential modal verbs 0.022 0.040
Perception verbs 0.056 0.035
Volitional verbs 0.251 0.239
Evidential modal discourse particles 0.006 0.006
First person personal pronouns 6.449 3.714
Second person personal pronouns 1.503 1.879
Third person personal pronouns 2.230 1.501
Objective backward causal connectives 0.034 0.029
Subjective backward causal connectives 1.336 1.312
Volitional backward causal connectives 0.202 0.151
Figure 2 presents the aggregated percentage markers for each corpus with each observation being one participant. Both datasets were inspected for normality; CGN (W = 0.99, p = 0.83) and SZ (W = 0.84, p = 0.002). A Wilcoxon rank sum test with continuity correction shows that there is a significant difference between the total percentage markers used between the CGN-data (SD = 1.863, M = 14.930) and SZ-data (SD = 2.324, M = 18.625) (W = 207, p < 0.001).
Figure 2. Violin and boxplot showing the aggregated percentage markers (y-axis) for each corpus (CGN vs. SZ) (x-axis) with each dot (i.e., observation) being one participant. The boxplot shows the corpora do not have a similar mean. The violin plot shows the distribution of the participants. There is a significant difference between the CGN-corpus and SZ-corpus between the percentage of markers (W = 207, p < 0.001), with CGN (SD = 1.863, M = 14.930) and SZ (SD = 2.324, M = 18.625).
Analysis 2: Differences per marker group
In order to see what drove the difference in use of (inter)subjectivity markers between the CGN-data and SZ-data as shown in the previous analysis, we looked at several categories of (inter)subjectivity markers that we defined in the Theoretical Background (see Appendix A).
Wilcoxon rank sum tests with continuity correction shows that there is a significant difference between the percentage markers used between the CGN-data and SZ-data for the evidential markers (W = 520, p < 0.001), first person personal pronouns (W = 47, p < 0.001), second person personal pronouns (W = 1203, p = 0.018), third person personal pronouns (W = 335, p < 0.001) and the volitional backward causal connectives (W = 645, p = 0.035). The
means and standard deviations per marker subgroup for each corpus for this analysis can be seen in Table 2. Figure 3 presents the aggregated percentage markers for each corpus with each observation being one participant for the above-mentioned marker groups.
Table 2
Means and standard deviations for the CGN corpus and the schizophrenic corpus.
CGN SZ
SD M SD M
Evidential markers 0.180 0.4797 0.190 0.628
First person personal pronouns 0.967 3.714 0.950 6.449
Second person personal pronouns 0.643 1.879 0.697 1.503
Third person personal pronouns 0.614 1.501 0.496 2.230
Figure 3. Violin and boxplots showing the aggregated percentage markers (y-axis) for each corpus (CGN vs. SZ) (x-axis) with each dot (i.e., observation) being one participant. The boxplots show that the corpora do not have a similar mean. The violin plots show the distribution of the participants. Figure A shows the evidential markers, B the first-person personal pronouns, C the second-person personal pronouns, D the third-person third-personal pronouns and E shows the volitional backward causal connectives.
difference between the percentage markers used between the CGN-data and SZ-data for the epistemic markers (W = 770.5, p = 0.271), subjective backward causal connectives (W = 818.5, p = 0.474) and objective backward causal connectives (W = 786.5, p = 0.306). The means and standard deviations per marker subgroup for each corpus for this analysis can be seen in Table 3. Figure 4 presents the aggregated percentage markers for each corpus with each observation being one participant for the above-mentioned marker groups.
Table 3
Means and standard deviations for the CGN corpus and the schizophrenic corpus.
CGN SZ
SD M SD M
Epistemic markers 1.077 5.891 1.374 6.274
Subjective backward causal connectives 0.684 1.312 0.421 1.336
observation) begin one participant. The boxplots show that the corpora do not have similar mean. The violin plots show the distribution of the participants. Figure A shows the epistemic markers, B the subjective backward causal connectives and C the objective causal connectives.
In this analysis we investigated how the subcategories (see Appendix A) of evidential and epistemic modality markers contributed to the difference in evidential and epistemic modality markers between the CGN-data and SZ-data, as shown in our previous analysis.
Wilcoxon rank sum tests with continuity correction did not show a significant difference between the percentage markers used between the CGN-data and SZ-data for the epistemic modal verbs (W = 884, p = 0.847) and epistemic modal discourse particles (W = 819, p = 0.476). However, a Wilcoxon rank sum test with continuity correction shows that there is a significant difference between the percentage CTMPs used between the CGN-data and SZ-data (W = 496, p < 0.001). The means and standard deviations per marker subgroup for each corpus for this analysis can be seen in Table 4. Figure 5 presents the aggregated percentage markers for each corpus with each observation being one participant for the above-mentioned marker groups.
Table 4
Means and standard deviations for the CGN corpus and the schizophrenic corpus.
CGN SZ
SD M SD M
Epistemic modal verbs 0.274 0.719 0.214 0.693
Cognitive Mental Predicates (CTMPs) 0.274 0.605 0.332 0.851
observation) begin one participant. The boxplots show that the corpora do not have similar mean. The violin plots show the distribution of the participants. Figure A shows the epistemic modal verbs, B the CTMPs, and C the epistemic modal discourse particles.
verbs and evidential modal discourse particles as per the marker list (see Appendix A). Wilcoxon rank sum tests with continuity correction did not show a significant difference between the percentage markers used between the CGN-data and SZ-data for the evidential modal verbs (W = 955.5, p = 0.701), volitional verbs (W = 836, p = 0.564), and evidential modal discourse particles (W = 769.5, p = 0.110). However, a Wilcoxon rank sum test with continuity correction shows that there is a significant difference between the percentage perception verbs used between the CGN-data and SZ-data (W = 344.5, p < 0.001). The means and standard deviations per marker subgroup for each corpus for this analysis can be seen in Table 5. Figure 6 presents the aggregated percentage markers for each corpus with each observation being one participant for the above-mentioned marker groups.
Table 5
Means and standard deviations for the CGN corpus and the schizophrenic corpus.
CGN SZ
SD M SD M
Evidential modal verbs 0.051 0.040 0.018 0.022
Perception verbs 0.037 0.035 0.057 0.056
Volitional verbs 0.129 0.239 0.113 0.251
observation) begin one participant. The boxplots show that the corpora do not have similar mean. The violin plots show the distribution of the participants. Figure A shows the evidential modal verbs, B the perception verbs, C the volitional verbs and D the evidential modal discourse particles.
In this study we explored the language use of people with a schizophrenia diagnosis compared to a benchmark corpus. We quantitatively analyzed narratives of people with a schizophrenia diagnosis and compared the frequency of the use of linguistic viewpoint markers. Our analyses showed that, as expected, participants with a schizophrenia diagnosis use significantly more first-person personal pronouns, which is in line with the literature and earlier findings. It also appears that, as expected, a benchmark corpus comprised of neurotypical narratives use significantly more second-person personal pronouns, which is also in line with the literature and earlier findings. However, we did not expect to find that the participants with a schizophrenia diagnosis in our study would use significantly more third-person personal pronouns, more volitional backward causal connectives (i.e., omdat) and more CTMPs than the benchmark corpus. These results point towards more perspective taking, instead of less, i.e., these markers express (inter)subjectivity and higher frequencies imply that one takes the perspective of the other into account. What is more, the increased frequency of subjectivity markers could also imply that participants acknowledge their own subjectivity to a greater extent.
We also found evidence, contrary to our expectations, for a significant difference in the evidential markers and perception verbs between participants with a schizophrenia diagnosis and a benchmark corpus; participants with a schizophrenia diagnosis used more evidential markers and perception verbs than a benchmark corpus. The difference between these expected and obtained results may not be reliable, since the small number of frequencies for this marker group (evidential markers) and subgroup (perception verbs), as they increase the chances of the results being false positives. Therefore, it might be beneficial for future studies to investigate these marker groups with a larger corpus. Nonetheless, is important to note that the significance of the evidential markers is probably driven by the significance of the perception
verbs, since this subgroup of evidential markers was the only subgroup that was significant. However, empirical studies have investigated the use of evidential markers in people with schizophrenia, especially words that denote sensory experiences, since people with schizophrenia can experience tactile and olfactory or gustatory hallucinations (Mueser, Bellack & Brady, 1990). A study by Mueser, Bellack and Brady (1990) shows that these kinds of hallucinations were strongly correlated with each other and with the severity of delusions for people diagnosed with schizophrenia. Similarly, Deutsch-Link (2016) found that people diagnosed with schizophrenia used more language related to perceptual experiences, especially words for hearing. An explanation for these findings is that perceptual experiences (e.g., visual or auditory hallucinations) that people with a schizophrenia diagnosis can have, are reflected in their language. What is more, verbs like hear or feel suggest a heightened degree of awareness of the speaker’s sensory processes and foregrounds the subjectivity of perception, retreating from a shared world. The same applies to non-factive expressions such as believe or assume (Zimmerer et al., 2017). These previous findings might explain the difference in expected (i.e., less) and obtained results (i.e., more) for the perception verbs, in that we found higher frequencies of perception verbs in participants with a schizophrenia diagnosis compared to a benchmark corpus.
Another explanation for the findings in our analysis is probably that our participants were not psychotic at the time of the interview. Theories and studies investigating schizophrenia might benefit from refraining to generalize schizophrenia as also including psychotic symptoms or psychotic episodes, and limit themselves to studying psychosis or individual symptoms in patients. An editorial by Guloksuz and van Os (2019) addresses the issues with the label schizophrenia and proposes benefits of changing the name and adopting a spectrum approach with an umbrella psychosis spectrum disorder (PSD) category with specifiers (Guloksuz & van Os, 2018). This umbrella spectrum disorder will be following in
the footsteps of the reconceptualization of ASD, where a person “will fall on a continuum, with some individuals showing mild symptoms and others having much more severe symptoms. This spectrum will allow clinicians to account for the variations in symptoms and behaviors from person to person” (American Psychiatric Association, 2013). For PSD, or psychotic phenomena, this continuum could be “conceptualized as a broad spectrum ranging from mild but persistent schizotypy to severe and recurrent schizophrenia” (Guloksuz & van Os, 2018, p. 8). Therefore, future studies could investigate people who are psychotic at the time of the interview and could investigate whether phenomenological and linguistic theories on schizophrenia could be empirically corroborated in people who experience psychosis at the time of the interview or language use.
Another explanation for the findings, is the comparability of our corpus with the benchmark corpus we used, the CGN. The results show the two corpora are only comparable in gender; region of residence and age differed between the two corpora. Our goal was to use the CGN as a benchmark for neurotypical language, not to have a control group composed of neurotypical controls to compare to our data. Seeing this goal, it was expected there would be differences in the demographics between the two corpora. Furthermore, these differences could also be due to the different goals with which each corpus was constructed. The project of the CGN was focused on the construction of a database of contemporary Dutch as spoken by adults in the Netherlands and Flanders. Our corpus, on the other hand, was constructed with the idea of obtaining life narratives by people with a schizophrenia diagnosis. Seeing these goals, the topics that were discussed also differed between the two corpora; talking about one’s hobby’s or job as a teacher in case of the CGN is very different from talking about one’s life, hardships, and day-to-day living. Seeing these differences in topic, it could be argued that we, for example, found a higher frequency of first-person personal pronoun use in participants with a schizophrenia diagnosis. In addition, the CGN is an older corpus (recorded in 1990) compared
to ours (recorded in 2018, 2019 and 2020), which might, therefore, also cause differences in language (e.g., expressions and vocabulary). What is more, the interviews of the CGN were each around 15 minutes, while the interviews that we recorded varied from half an hour to over two hours. The CGN interviews were recorded at schools where the teachers that were interviewed worked, whereas our interviews were mostly conducted at the home of the participant. Seeing all these differences, future research could use a larger control group composed of neurotypical controls using the clean interview method we applied in this study (see Lawley & Tompkins, 2000), in a similar interview setting, with similar topics and geographical origins of the participants and record these interviews at similar times as the other corpus in order to create a comparable corpus, instead of a benchmark corpus, to compare with the corpus that was constructed in the current study.
Our results show that the label ‘schizophrenia’ is not a label that can account for all the variability that we see in people with a schizophrenia diagnosis. That is, participants in our corpus show that there is variability in the (average) percentage (inter)subjectivity markers they use (see Figure 2 to 6), which might help support the proposition of Guloksuz and van Os (2019) to change the label ‘schizophrenia’ to an umbrella term: PSD.
In conclusion, we did not find evidence for generalizable differences, based on the literature and previous findings we discussed, in the use of lexical viewpoint markers when comparing the language use of people with a schizophrenia diagnosis to that of a benchmark corpus. We demonstrated, however, a possible method of investigating linguistic viewpoint markers as a method to quantitatively investigate viewpoint and perspective in language. A qualitative way to investigate viewpoint, perspectives and language has already been proposed by van Schuppen, van Krieken and Sanders (2019). They propose the Deictic Navigation Network (DNN), which isa way of envisioning and analyzing perspectives in narratives and which is based on Mental Space Analysis (Fauconnier & Sweetser, 1996) and helps to identify
linguistic markers of perspective in intersubjective discourse. A combination of a quantitative study like the one presented here and a qualitative analysis, which makes use of the DNN, could further bridge the gap between the fields of linguistics, philosophy and psychiatry. All in all, the results we presented provide a foundation for further studies investigating the cognitive linguistic aspects of the phenomenon of schizophrenia, and the relationship between linguistic and cognitive perspective-taking in general.
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Marker group Marker subgroup Marker Class Singular/plural
Epistemic marker epistemic modal verb zou verb
Epistemic marker epistemic modal verb zouden verb
Epistemic marker epistemic modal verb zult verb
Epistemic marker epistemic modal verb zal verb
Epistemic marker epistemic modal verb zullen verb
Epistemic marker epistemic modal verb kan verb
Epistemic marker epistemic modal verb kunnen verb
Epistemic marker epistemic modal verb kunt verb
Epistemic marker epistemic modal verb gekund verb
Epistemic marker epistemic modal verb kon verb
Epistemic marker epistemic modal verb konden verb
Epistemic marker Complement-Taking Mental Predicates (cognitive verb)
