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 Table of Contents  
ORIGINAL ARTICLE
Year : 2022  |  Volume : 6  |  Issue : 2  |  Page : 164-168

Irony comprehension in schizophrenia: Development, content validity and “Known-Groups” validity of an Indian, comic-based, computerized task


1 Department of Psychology, Jamia Millia Islamia, New Delhi, India
2 Department of Humanities and Social Sciences, India Institute of Technology, Kharagpur, West Bengal, India
3 Department of Clinical Psychology, Postgraduate Institute of Behavioral and Medical Sciences, Raipur, Chhattisgarh, India
4 Department of Psychiatry, Central Institute of Psychiatry, Ranchi, Jharkhand, India
5 Department of Psychiatry, All India Institute of Medical Sciences, Bibinagar, Hyderabad, India

Date of Submission10-May-2022
Date of Decision28-May-2022
Date of Acceptance11-Jun-2022
Date of Web Publication19-Aug-2022

Correspondence Address:
Dr. Sai Krishna Tikka
Department of Psychiatry, All India Institute of Medical Sciences, Bibinagar, Hyderabad
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/aip.aip_89_22

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  Abstract 


Introduction: Irony comprehension (IC) has been described as a schizophrenia (SCZ) disease marker. High variability exists in the measurement of IC. We aimed to assess content and “known-groups” validity of an Indian, comic-based, computerized-IC task. Methods: A 15-story IC task was prepared. Content validity of the IC task stimuli was assessed by experts in mental health. Performance on the IC task was compared between 15 SCZ patients and 15 healthy controls (HC). Known-groups validity was assessed using discriminant function analysis. Results: Content validity of the IC task was optimum. Lower number of correct responses and longer reaction times for irony stimuli were seen in SCZ patients, compared to HC. Both these measures showed 100% accuracy in discriminating SCZ from HC, therefore, implying excellent “known-groups” validity. Conclusion: The newly designed IC task has good psychometric properties, in terms of content and “known-groups” validity.

Keywords: Schizophrenia, social cognition, validity, verbal irony


How to cite this article:
Walia T, Agashe S, Tikka DL, Ram D, Das B, Tikka SK. Irony comprehension in schizophrenia: Development, content validity and “Known-Groups” validity of an Indian, comic-based, computerized task. Ann Indian Psychiatry 2022;6:164-8

How to cite this URL:
Walia T, Agashe S, Tikka DL, Ram D, Das B, Tikka SK. Irony comprehension in schizophrenia: Development, content validity and “Known-Groups” validity of an Indian, comic-based, computerized task. Ann Indian Psychiatry [serial online] 2022 [cited 2022 Sep 25];6:164-8. Available from: https://www.anip.co.in/text.asp?2022/6/2/164/354124




  Introduction Top


Aberrant integration of external perceptual signals with internal predictions leads to impaired predictive coding, which consequently results in erroneous appraisal of the internal world model.[1],[2] Inappropriate attribution of significance to external stimuli, also termed as “aberrant salience,” has been suggested to underpin development of schizophrenia (SCZ) psychopathology.[3]

Such erroneous predictions and attributions are greater when the perceptual stimuli are ambiguous.[2] The most common of the ambiguous stimuli in social conversations is verbal irony; ambiguity is inherent to verbal irony.[4] Ironic statements pose a comprehension challenge. Here what is said is the exact opposite of what is intended (e.g., remark 'food was awesome' when in fact the food remained uncooked). As irony comprehension (IC) and unmasking ambiguity have a close relationship,[4] its research in SCZ becomes important. Unsurprisingly, IC has been found to be defective in SCZ, even during remission.[5],[6] Defective IC and consequent misinterpretation have been shown to contribute to development or worsening of delusions,[7] therefore leading to symptomatic relapse. On the other hand, these deficits result in poor social functioning; they may also lead to symptomatic relapse. In fact, IC is closely related to comprehending metaphors, i.e., figurative expressions[8] and efficient use of sense of humor, which is known to have positive influence on social functioning.[9] Perhaps, better understanding of mechanisms underlying IC may help develop training modules to improve social communication in SCZ.

IC is assessed by measuring performance on certain experimental tasks. These tasks typically involve a scenario/story leading up to a character stating either ironic or literal sentence, which the subject has to recognize. Our literature review found that tasks exploring IC significantly vary in the number of stories/scenarios, kind of stimuli, and mode of presentation. The number of stories vary from 1 to 120, median being 16.[6],[10],[11],[12],[13],[14],[15],[16],[17],[18],[19],[20],[21],[22] While majority of them used sentence based stimuli,[6],[11],[12],[13],[15],[16],[17],[18],[19],[20],[21] a few of them have image-[10] and video-based[12],[22] stimuli; one task uses bilateral chat history as the stimulus too.[22] While neuroimaging studies have used computerized presentation mode,[10],[11],[18],[19],[20],[21],[22] all other studies have presented stimuli in a manual mode. Majority of the studies have task stimuli in English and are conducted on native English-speaking populations. However, studies from nonnative English populations have used native languages,[6],[10],[17],[22] one of them being Indian.[17]

With only one available Indian validated task, which has only 2 sentence-based stories that are presented manually, we aimed to validate content of a computerized, Hindi, color-comic image-based IC task consisting of 15 stories, in this study. We also aimed to assess IC in remitted SCZ patients, in comparison to healthy controls (HCs), and assess its “known-groups” or discriminant validity.


  Methods Top


The study was approved by the institute ethics committee. Written informed consent was taken from all the participants (and their primary caregivers in case of patients) before enrolling them for the study.

Irony comprehension task

Stimulus preparation

The task used for this study was prepared using certain comic characters and situations. The comics were prepared using characters and situations available on www.pixton.com (free version). Each of the character was customized such that they represent characters of Indian culture. The language used in these stimuli was exclusively Hindi.

This task was adopted from Rapp et al.'s[18] “sentence-” based task used in an fMRI experiment and the “metaphor-irony” task of the Social Cognition Rating Tools in Indian Setting (SOCRATIS) test battery.[17] The task was presented in a set of 15 stories. Out of these 15 stories, 4 of the them depicted a single character, while the rest of the 11 stories depicted two characters, in a social situation. There was no repetition of characters in any of the stories. Each story consisted of 4 separate stimuli [Figure 1]:
Figure 1: The sample stimuli used to test irony comprehension (source: Original)

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  • 1st stimulus depicted a scene with character/s in a social situation along with a sentence describing the character/s and the situation. This visual stimulus was simultaneously presented with prerecorded audio narration of the situation
  • 2nd stimulus/3rd stimulus/4th stimulus consisted of another scene with a judgmental phrase related to the situation by one of the characters. The phrase was either an ironic or a logical or a missense statement specific to the situation, respective to 2nd/3rd/4th stimuli. These sentences were shown in dialogue boxes. The sentences in the ironical and logical statements were matched for number of words in them. The missense sentence stated a universally true statement but completely irrelevant to the situation. These visual stimuli were simultaneously presented with prerecorded audio narration of the situation.


The stimuli were categorized, roughly equally, based on the emotional valence of expressions of characters. The first stimuli, which depicted the social situation for each story, were categorized into those that showed negative emotional (8) and neutral (7) emotional valence of the characters. Emotional valence of the 2nd, 3rd, and the 4th stimulus was constant for each story; 8 and 7 of them showed incongruent and congruent emotional valence of expressions between the two characters (or between the emotional expression and verbal irony content in those stories with a single character), respectively.

Stimulus presentation

The first stimulus was presented till the subject indicated that he has fully understood the situations and the images in the story. After the presentation of the first stimulus, the second, third, and fourth stimuli were repeated twice each in a random order, i.e., a total of 90 response-seeking stimuli were presented (30 irony, 30 logical, and 30 missense). The second, third, and fourth stimuli were presented for 10 s duration each, wherein the subject had to press 1, 2, or 3 for irony, logical, and missense responses, respectively, immediately and after the completion of audio narration, which was for a duration of 3500 ms. In this manner, 15 stories were presented one after the other.

The task was presented using E-prime (E-prime 2.0, psychology software tools, E-prime Inc. Denver, USA). The number of correct, incorrect, and missed responses was calculated for each response, for each story, and for every subject. Percentage of correct responses (i.e., correct responses × 100/total responses) was taken as the measure of accuracy of performance. The reaction times for each of these responses were also recorded.

Participants

Patients were recruited by purposive sampling from the outpatient services of a tertiary care mental health institute. Sixteen right-handed, male patients in the age group of 18–50 years, with first episode of SCZ as per ICD-10 DCR,[23] meeting clinical remission[24] on the Positive and Negative Syndrome Scale (PANSS)[25] items, were taken up for the study in the “SCZ” group. Patients in clinical remission were primary chosen considering their better cooperation levels compared to symptomatic patients. Cooperation levels were deemed important as the study was conducted in laboratory settings. Patients on stable dose of antipsychotic medication were recruited; antipsychotic equivalents were calculated according to the minimum effective dose method.[26] Patients having a history of neurological illness, significant head injury, comorbid substance dependence (excluding nicotine and caffeine), other psychiatric disorders, disruptive behavior (suicidal or homicidal) that warranted immediate intervention, or history of electroconvulsive therapy within previous 6 months were excluded. The “HC” group included fifteen right-handed, age-matched subjects, recruited from the hospital staff and community living in the vicinity of the institute. HC were screened with General Health Questionnaire-12;[27] only those with scores < 3 were included. In addition, all the participants required a minimum 8 years of formal education, normal vision and hearing, and sufficient mastery in Hindi to undergo the task. Relevant sociodemographic and clinical data were collected from all the participants.

Analysis

Content validity

Eleven consultants/senior residents/clinical and child psychologists/research officers from the departments of psychiatry, clinical psychology, and psychiatric social work (having experience of working in cognitive neurosciences; mean experience in mental health = 9.36 years and proficiency in spoken as well as written Hindi language) rated 15 stories (sets of stimuli) on three questions: whether the stimulus (1) tested the construct of IC as in the original, (2) depicts “Indianness” of characters and situations, and (3) is ideal for computerized experiments on a Likert scale (1 = strongly disagree; 5 = strongly agree). Stories that received a score of < 4 (agree) from > 25% of the experts were deemed excluded.

Statistical methods

Group differences and clinical characteristics for the continuous and categorical variables were computed using independent samples t-test and Fisher's exact test, respectively. Scores on attribution bias questionnaire, social functioning, and measures of the IC task were compared using independent samples t-test. For examining “known-groups validity,” we conducted discriminant function analysis. The level of significance was kept at 0.05. Statistical analysis was done using IBM SPSS for Windows, Version 21.0 (IBM Corp., Armonk, NY, USA).


  Results Top


Content validity

None of the 15 stories received a score of < 4 (agree) from > 25% of experts. Average scores on content validity, “Indianness,” and computerized presentation suitability for the 15 IC stories used were 4.84, 4.72, and 4.58, respectively.

Sociodemographic and clinical profile

All participants were men. One of the patients included in the patient group had to be dropped due to inappropriate responding; data from 15 patients and 15 controls were analyzed. Age of the participants in the patient group (30.40 [6.65]) was comparable (t = 1.11; P = 0.28) to those in the control group (28.13 [4.26]). Both the groups were also comparable on marital status (χ2 = 1.68; P = 0.39), occupation (χ2 = 1.22; P = 0.46), and habitat (χ2 = 2.22; P = 0.26). Income of the patient group (Rs. 7133.33 (1684.67)) was found to be significantly lower (t = 2.41; P < 0.05) than that of the control group (Rs. 10266.67 (4742.92)). Furthermore, subjects in the patient group had significantly lower levels of education than the control group (χ2 = 6.92; P < 0.05).

Among SCZ group, the mean age of onset and duration of illness were 28.13 (5.65) years and 19.07 (5.92) months, respectively. The mean antipsychotic dose equivalents was 1.19 (0.73). The mean PANSS scores for positive, negative, general psychopathology, and total were 10.07 (2.28), 11.00 (1.60), 18.6 (1.81), and 39.67 (3.06), respectively.

Irony comprehension task performance

[Table 1] also shows the comparison and known-groups validity for measures of performance on the 'irony comprehension' task. Both percentage of correct responses and reaction times, for both irony and logical stimuli, were significantly lower in SCZ compared to HC. Both percentage of correct responses and reaction times for irony stimuli could discriminate SCZ from HC with 100% accuracy. For logical stimuli, percentage of correct responses and reaction times were 83.3% and 96.7% accurate, respectively.
Table 1: Measures of comparison and known-groups validity of percentage of correct responses and reaction times on the “irony comprehension” task

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  Discussion Top


Our study provides evidence for good to excellent content and known-groups validity for the task studied. These psychometric properties are similar to those of other standardized IC tasks for use in India.[17] Moreover, the present task involves more stimuli and a computerized mode of presentation, which allows for more objective assessment, including that of reaction times. In addition, computerized mode of stimulus presentation allows for assessments that may be offline as well as online (i.e., presentation during online EEG, fMRI, etc.).

IC requires higher order social cognitive abilities. It involves integration of several processes: understanding literal content, social contexts such as speaker's beliefs and emotional attitudes, and nonverbal cues such as facial expression. As facial expression recognition and discrimination has been found to be deficient in SCZ patients,[28] controlling for this domain becomes mandatory. Hence, preparation of stimuli in the present task involved proportionate use of neutral, positive, and negative emotional valence of expressions of the characters. Moreover, it has been shown that efforts invested in comprehending irony, which in itself has a higher order cognitive demand among the various communicative phenomenon, increase with the use of nonnative language in stimuli.[12] Therefore, use of Hindi as the stimulus content language is scientifically justified.

SCZ patients showed inaccurate responses and longer reaction times on both the task conditions (irony/logical), suggesting deficit in irony-metaphor comprehension. Apart from specific deficits in IC, recent reviews suggest consistent impairments in metaphor comprehension in SCZ patients.[8],[9] Moreover, the performance on IC and logical (metaphor comprehension) task stimuli discriminated SCZ patients from HC with high accuracy, the discrimination accuracy being greater for IC than the logical (metaphor comprehension) task stimuli. As the patients in the current study met the criteria for clinical remission, our study results imply that IC deficits are fairly existent despite improvement in clinical symptoms. Studies in the past too demonstrate such defects.[18],[29] With a methodological advancement in the use of color comics with simultaneous voice over in the tasks, rather than the use of a “sentence based” as in the past studies, we consider our finding to be better binding. Further, our findings second the recommendation that such IC deficits are indeed trait markers.[30],[31]

Literature suggests a significant relationship between IC and theory of mind (ToM), which is the ability to attribute mental states to others.[6],[10],[13],[14],[32] Besides, SCZ and autism, where ToM deficits were first described, they have now been shown to be present in a range of psychiatric disorders– affective disorders (both major depressive[33] and bipolar disoder[34]), alcohol use disorders,[35] somatoform disorders,[36] etc. It might be extremely interesting to understand the ability to comprehend irony and its relationship with ToM in these disorders as well. Recently, the influence of personality traits (i.e., schizotypal, borderline, and autistic) on IC has also been assessed.[22] With growing research among child and adolescents with SCZ, affective and substance use disorders, use of comic based stimuli in the task, might have specific implications.

Limitations

The major limitation of the study was that other reliable and validity measures, internal consistency, concurrent validity, and factor structure remain to be explored. Although we consider the use of color comics with simultaneous voice-over, rather than the use of a “sentence based” ones, as a methodological advancement in the tasks, clarification by comparing each of theirs criterion validity scores is certainly needed. Small sample size limits generalizing the findings. The sample size was chosen considering the time-limited nature of the study (masters degree dissertation) without priori sample size estimation and therefore the results of comparison analysis may be considered exploratory. Inclusion of only male participants might be another limiting factor, as gender differences in IC have been debated upon.[37] Furthermore, lack of education matching between the two study groups is an important limitation too. As the patient population were in clinical remission and the experiment conducted in a laboratory setup, the findings cannot be extrapolated onto, symptomatic patients and real-life settings. Apart from ironic criticism, which was exclusively used in the verbal irony stimuli used in the present task, ironic praise[22],[38] might also be examined in future studies.


  Conclusion Top


This Indian, comic-based, computerized IC task has optimum content and an excellent “known-groups” validity. The study findings reiterate that irony and metaphor comprehension is impaired in SCZ.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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