ABSTRACT
Background:
Schizoaffective disorder (SAD), in current literature, lies clinically and prognostically between schizophrenia (SCZ) and bipolar affective disorder (BPAD), with some overlapping neuropsychological deficits in them.
Aim:
The aim of this study was to investigate whether there was any difference in executive functions among patients of schizoaffective disorder (SAD), schizophrenia (SCZ), bipolar affective disorder with psychotic symptoms (BPAD) and normal controls (NC).
Methods:
Data were collected by a non-probability purposive sampling technique from a total of 114 psychotic in-patients using inclusion and exclusion criteria. Using standard laboratory procedure, executive functions (Trail Making Test, TMT; Stroop Color-Word Test, SCWT; Spatial Working Memory, SWM; Stockings of Cambridge, SOC; Intra-Extra Dimensional Set Shift, IEDS) of 23 consecutive consenting clinically stable patients of SAD (manic type) were compared with 23 matched (age, gender and handedness) consenting clinically stable patients of each SCZ, psychotic BPAD and NC subjects.
Results:
Significantly more executive function deficits due to low CW score (F = 35.11,95% CI = 32.12 to 37.09, P < .001), more Stroop interference (F = 6.53,95% CI = 5.12 to 7.11, P < .001) in SCWT and more SWM errors (F = 19.08,95% CI = 17.42 to 21.34, P < .001) were noted in SAD patients than BPAD patients. NC and bipolar group had gradually reduced their percentage of bets in CGT, as they passed through higher probability to lower probability ratios. But both SAD and SCZ patients could not follow this concept, and thus they showed more impulsivity or risk-taking behavior.
Conclusion:
The CW score, and Stroop interference and number of errors of SWM can differentiate SAD patients from BPAD. The percentage of bets placed in different probability ratios in CGT can differentiate SAD and SCZ patients from BPAD patients neuropsychologically.
Keywords: Executive function, gambling, neuropsychology, schizoaffective disorder
INTRODUCTION
The conceptual issues of schizoaffective disorder (SAD) are of recent interest. In terms of clinical manifestations, schizoaffective disorder (SAD) occupies an intermediate position between schizophrenia (SCZ) and bipolar affective disorder (BPAD), with some studies favoring a closer proximity to schizophrenia and others to psychotic mood disorders.[1] Parallel to it “executive function” is a way to understand the implicit instrumental process for cognition and behavior. Executive function is a multi-faceted construct including the ability for planning, directing and maintaining attention, organization, abstract reasoning, problem-solving, self-regulation and motor control.[2,3] Compared with normal controls in past literature, executive functions in BPAD, SCZ and SAD patients also showed diverse results. In some studies, all three performed poorly across neurocognitive measures. Interestingly, in some studies, mood disorder patients without a history of psychosis showed impairment only in processing speed.[4] After controlling for age and socioeconomic status, Hooper et al.[5] and Tümkaya et al.[6] found loss of significance in differences between SCZ and SAD groups regarding working memory and problem-solving ability. SCZ patients performed worse in the domains like mental speed, executive function, concept formation and shifting ability when compared with SAD or psychotic mood disorder patients in another study by Bora et al.[7] The SAD patients of Torrent et al.[8] reported greater impairment than normal controls and bipolar patients in the domains of executive function including attentional measures.
Because of the overlapping as well as contradictory published findings of executive functions in these psychotic illnesses and the relative scarcity of published well-organized empirical research data, the current study felt a need to reinvestigate all clinically relevant executive functions to avoid premature and oversimplified conclusions. Keeping in mind also the potential validity of SAD as a disease entity separate from SCZ and affective disorder in our classificatory system, the present study sought a comparison of different dimensions of executive functions in patients of SAD, SCZ, BPAD with psychotic symptoms and normal controls (NC).
METHODOLOGY
Ethical considerations
Permission from Institutional Review Board (IRB) had been taken.
Aims and objectives
The aim of this study was to investigate whether there was any difference in executive functions among patients of SAD, SCZ, BPAD with psychotic symptoms and NC. The objectives were to use standard laboratory procedure to assess and compare the Stroop interference, spatial working memory, dimensional set shifting ability and concept of percentage of bets used as one passes through a higher probability to lower probability tasks between 23 patients of SAD (manic type) and 23 matched (age, gender and handedness) patients of each SCZ, psychotic BPAD and NC groups.
Sample size estimation
Sample size was calculated taking the confidence interval of 95% and the power of the study to be 80%. Taking E/S = 0.75 (ratio of difference of mean value of and their respective SD in SAD and SCZ) from the previous study,[9] we found sample required for each group as about 24.
Data collection/study procedure
The sample was selected using the non-probability purposive sampling technique over a period of two years (2008–2010). This study was conducted in the neuropsychology lab of the Central Institute of Psychiatry, Ranchi [Supplementary file S1 (436.4KB, tif) ]. The treating team managed the patients with drugs and psychosocial interventions independently. A detailed physical examination was done to rule out the presence of major medical or neurological disease. In this study a total 114 patients who were treated for more than a month in different psychiatry wards of our institute diagnosed according to the criteria of ICD-10 DCR[10] by senior resident or consultant as SAD (F = 25.0) (N = 39), SCZ (F 20.0) (N = 37) and BPAD with psychotic symptoms (F = 31.2) (N = 38) were taken to screen for inclusion [18–60 years old clinically stable for more than 15 days (i.e. scores of BPRS ≤ 30 and YMRS ≤12 or HDRS ≤7)]patients with normal (or corrected to normal) vision and hearing, able to comply with the test requirement] and exclusion criteria [ history of major medical and neurological disorder (like head injury, encephalitis etc), co-morbid major psychiatric disorder (like clinically disorder of intellectual development etc), substance use (harmful use or dependence except in nicotine and caffeine), and had a electroconvulsive therapy session within the past 6 months ] of this study. Out of the initially selected 26 consecutive consenting patients of SAD, three were excluded because of noncooperation (one), eye strain from the computer screen (one) and cold sensitivity to air conditioning of the CANTAB (Cambridge Neuropsychological Test Automated Battery) lab (one). All 23 finally selected SAD patients were right-handed. Consecutive consenting (either by clinically stable and competent patients themselves or their family members), 25 SCZ patients and 25 BPAD patients were selected after matching (with respect to age, sex and handedness) with the SAD group. Two of the SCZ patients were excluded subsequently because of incomplete data in IED (Intra-Extra Dimensional Shift) and/or SOC (Stockings of Cambridge). Two of the BPAD patients were excluded from the study (one because of noncooperation for CANTAB, and one to maintain the homogeneity of this group in terms of age outlier). Similarly, “normal controls” group (N = 23) was selected from right-handed persons accompanying patients of the dermatology OPD of our institute who scored GHQ ≤2 with normal vision and hearing, ability to comply with the test requirements without past and family history of psychiatric illness, after matching with the SAD group with respect to age and gender.
Study tools
To ensure handedness, the Edinburgh Handedness Inventory[11] was administered. This is required to exclude the confounding due to the handedness difference between subjects in different neuropsychological indices. Written informed consent from all participants was taken after explaining the procedure in detail. Then, sociodemographic information and other relevant clinical data were gathered from all the subjects. Patients were classified socio-economically by the Modified Kuppuswamy scale.[12] Fifteen patients were on typical antipsychotics (haloperidol, chlorpromazine, clozapine, thioridazine, pimozide, etc.), 38 patients were on atypical antipsychotic (clozapine, risperidone, olanzapine, aripiprazole, etc.), and the remaining 16 patients were on both. Moreover, mood stabilizers (carbamazepine, oxcarbazepine, sodium valproate, lamotrigine, etc.) were administered to all the BPAD and 21 SAD patients. An additional antidepressant (Escitalopram, sertraline, venlafaxine, etc.) treatment was in 4 SCZ patients. 5 each of SAD and BPAD patients had received electroconvulsive therapy (ECT) in their previous episodes (>6 months prior).
Finally, all participants were subjected individually to the standard laboratory procedure to assess their executive function, which took around 2–3 hours each using the Trail Making Test (TMT), Stroop Color-Word Test (SCWT), Spatial Working Memory (SWM), Stockings of Cambridge (SOC), Intra-Extra Dimensional Set Shift (IED) and Cambridge Gambling Task (CGT). The sequence of tests was identical for each participant. Outcome measures of individual tests were stored in an optical disk as an Excel and HTML file.
Calculation of neuropsychological indices
TMT interference was defined as the B/A ratio of performance in the TMT.[12] The time needed to perform the third task (i.e. reading color names) was calculated by subtracting the predicted Color-Word score [pCW = (WxC)/(W + C)] from the CW. The initial thinking time of SOC is derived by subtracting the time taken to complete the first move of each problem during the control phase from that of the planning phase.[13] The subsequent thinking time derived by subtracting the time to complete the task after the first move during the control phase from that of the planning phase.[14] The total adjusted error of IED was defined as the error score adjusted for whether the entire task is completed.[15] Quality of decision making (Proportion Correct) was the proportion of trials on which subjects chose the more likely outcome. Risk adjustment (Percentage bet) is calculated by averaging the percentage staked for all those trials that were gambled in relation to certain ratios of colored boxes, like red: blue box ratio 9:1 or 8:2 or 7:3 or 6:4.
Statistical analyses were performed with the Statistical Package for the Social Sciences (SPSS), version 20. Preliminary analysis consisted of dealing with missing data and thus n had been less than 23 in such cases (as it had been seen in case of CGT). The distribution pattern (normal or not) of variables was identified by Kolmogorov-Smirnov tests, histograms and Q–Q plots. Then, potential outliers were identified; these were data points far outside the area covered by the normal distribution. Data that were not normally distributed were transformed using log base 10 transformations to reduce skewness in the distribution, except those variables with large values or zeros where square root transformation or log 10 (Xi + 1) transformation had been conducted respectively. ANOVA was run with all neuropsychological variables as dependent variables. The Pearson Chi-square (Χ²) test, t test and one-way ANOVA (with Tukey post hoc) were used (e.g., for duration of active and untreated psychosis, CPZ equivalent, etc.) as per requirement. Kruskal–Wallis non-parametric analysis of variance was applied to variables which did not approximate normal distributions (e.g., duration of current episode, etc.). Follow-up comparisons between groups were performed using the Mann-Whitney U-test, with U scores transformed into the normally distributed z-statistic. using the Mann-Whitney U-test, with U scores transformed into the normally distributed z-statistic.
RESULTS
Sociodemographic details
All four groups were similar in terms of age (F = 0.60, P = 0.61), years of education (F = 2.14, P = 0.10) and socioeconomic status (F = 2.52, P = 0.87) [Supplementary Table S2]. Majority of the participants were male (52.2%), married (68.48%) and hailed from lower socioeconomic class (40.22%). 54.35% participants never consumed psychoactive substances. The SCZ patients were of paranoid (N = 17), undifferentiated (N = 4) or schizophrenia unspecified (N = 2) type. All 23 patients of the BPAD group had mood-congruent psychotic symptoms. The majority of patients were from rural areas (59.42%), but normal controls were predominantly from an urban background (78.3%) (c2 = 10.61, P = 0.01). Unemployment was significantly higher in participants with SCZ (47.8%) than the other two psychotic groups (30.4% each), and NC (21.7%) (c2 = 12.95, P =0.04).
Table S2.
Comparison of Sociodemographic profile among the groups
| Sample character | SAD group (n=23) | SCZ group (n=23) | BPAD group (n=23) | NC group (n=23) | F/χ2 (df) | P |
|---|---|---|---|---|---|---|
| n (%) | n (%) | n (%) | n (%) | |||
| Age in years | 35.96 (7.35) | 34.26 (6.94) | 33.07 (9.04) | 35.26 (7.62) | .60 (3,88) | .61 |
| Education in years | 9.91 (3.92) | 11.93 (3.16) | 11.83 (3.19) | 10.22 (3.54) | 2.14 (3,88) | .10 |
| Gender | ||||||
| Male | 12 (52.2) | 12 (52.2) | 12 (52.2) | 12 (52.2) | .000 (3) | 1.00 |
| Female | 11 (47.8) | 11 (47.8) | 11 (47.8) | 11 (47.8) | ||
| Domicile | ||||||
| Rural | 14 (60.9) | 12 (52.2) | 15 (65.2) | 5 (21.7) | 10.61* (3) | .01 |
| Urban | 9 (39.1) | 11 (47.8) | 8 (34.8) | 18 (78.3) | ||
| Marital status | ||||||
| Single | 7 (30.4) | 11 (47.8) | 6 (26.1) | 5 (21.7) | 4.18 (3) | .24 |
| Married | 16 (69.6) | 12 (52.2) | 17 (73.9) | 18 (78.3) | ||
| Occupation | ||||||
| Housewife | 7 (30.4) | 5 (21.7) | 7 (30.4) | 1 (4.3) | 12.95* (6) | .04 (exact) |
| Unemployed | 7 (30.4) | 11 (47.8) | 7 (30.4) | 5 (21.7) | ||
| Employed | 9 (39.1) | 7 (30.4) | 9 (39.1) | 17 (73.9) | ||
| Kuppuswamy’s socio- economic class | ||||||
| Upper class | 7 (30.4) | 8 (34.8) | 10 (43.5) | 7 (30.4) | 2.52 (6) | .87 (exact) |
| Middle class | 6 (26.1) | 4 (17.4) | 6 (26.1) | 7 (30.4) | ||
| Lower class | 10 (43.5) | 11 (47.8) | 7 (30.4) | 9 (39.1) | ||
| Substance use | ||||||
| Never | 15 (65.2) | 13 (56.5) | 12 (52.2) | 10 (43.5) | 2.28 (3) | .52 |
| Occasional | 8 (34.8) | 10 (43.5) | 11 (47.8) | 13 (56.5) |
SAD=schizoaffective disorder, SCZ=schizophrenia, BPAD=psychotic bipolar affective disorder, NC=normal controls, F where test used is ANOVA, χ2 where test used is Chi-squire, *means P significant at 0.05, df=degree of freedom
Clinical details
SAD group had significantly longer mean duration (months) of current episode (21.41 ± 42.94) as compared to BPAD (3.35 ± 1.43), but shorter than SCZ group (65.85 ± 53.25) (H = 32.15, P < 0.01) [Supplementary Table S3]. But the BAD group (3.13 ± 2.90) had significantly more prior episodes compared to the SCZ group (.26 ± 1.25) (H = 34.36, P < 0.01). Duration (in months) of active psychosis and untreated psychosis both were prolonged in both SAD (56.39 ± 45.41 and 30.89 ± 28.31, respectively) and SCZ group (44.65 ± 30.10 and 34.57 ± 24.01, respectively) compared to BAD group (17.87 ± 12.76 and 11.30 ± 8.95, respectively) (F = 7.51, P < 0.01 and F = 7.37, P < 0.01, respectively). The SAD group mostly (65.2%) followed an episodic course (with either progressive or stable deficit), and the SCZ group mostly (87%) followed a continuous course (F = 24, P < 0.01). We have operationally defined the episodic nature of psychotic illness in our study as an illness having at least one instance of more than eight weeks with sub-threshold symptoms (as per ICD-10 DCR[10]) or no symptoms, and non-substantial impairment in the activity of daily life. There were no significant differences in total scores of BPRS and YMRS (F = 0.15, P = 0.87 and t =−.51, P = 0.14, respectively) among these three psychotic groups. All three psychotic groups were treated with similar CPZ equivalent doses of AP (Mean dose in SAD 486.65 mg, SCZ 454.35 mg and BPAD 334.64 mg; F = 206, P = 0.8).
Table S3.
Comparison of clinical profile among groups
| Clinical characteristics (n=69) | SAD groupa Mean (SD) | SCZ groupb Mean (SD) | BPAD groupc Mean (SD) | F/H/t/χ2 (df) | P (Post hoc) |
|---|---|---|---|---|---|
| Duration of current episode (in months) | 21.41 (42.94) | 65.85 (53.25) | 3.35 (1.43) | 32.15** (2) | <.01 (c<a<b) |
| Number of previous episodes | 1.96 (2.10) | .26 (1.25) | 3.13 (2.90) | 34.36** (2) | <.01 (c>b) |
| Duration of active psychosis (in months) | 56.39 (45.41) | 44.65 (30.10) | 17.87 (12.76) | 7.51** (2,66) | <.01 (a, b>c) |
| Duration of untreated psychosis (in months) | 30.89 (28.31) | 34.57 (24.01) | 11.30 (8.95) | 7.37** (2,66) | <.01 (a, b>c) |
| CPZ equivalence of AP (current) | 487.65 (310.62) | 454.35 (290.47) | 334.64 (169.81) | 2.60 (2,66) | .08 |
| Pattern of course (n=46) | |||||
| Continuous | 5 (21.7) | 20 (87.0) | |||
| Episodic with deficit | 15 (65.2) | 0 (0) | N/A | 24.00**(2) | <.01 (exact) |
| Incomplete remission | 3 (13.0) | 3 (13.0) | |||
| BPRS total score | 21.74 (2.40) | 22.04 (2.20) | 22.04 (2.01) | .15 (2,66) | .87 |
| YMRS total score | 6.78 (2.35) | 7.91 (2.71) | -1.51 (44) | .14 |
SAD=schizoaffective disordera, SCZ=schizophreniab, BPAD=psychotic bipolar affective disorderc, F where test used is ANOVA, χ2 where test used is Chi-squire, ** means P significant at 0.01, df=degree of freedom
Executive functions details
Executive functions like time taken for completion of TMT, number of error committed during TMT B, IED and SWM; SCWT scores of Word (W), color (C) and word-color [Figure 1], mean initial thinking time for five moves of SOC, SWM strategy, number of problems of SOC solved in minimum moves [Figure 2], total earned points and number of lost blocks in CGT as expected were impaired in all three psychiatric patients than normal participants. The number of errors committed during TMT A was significantly higher in the SCZ (P = 0.04) and BAD group (P < 0.01) than in the normal control. SAD patients scored less in CW (P < 0.01) and faced more Stroop interference (F = 6.532, P < 0.01) than bipolar participants [Figure 1].
Figure 1.
Line graph of different SCWT indices among four groups of patients
Figure 2.
Bar diagram showing executive functions from SOC and SWM among four groups of patients
SAD patients executed a larger number of errors in SWM than the BAD group (P = 0.01). Mean subsequent thinking time for five moves of SOC was significantly longer in the SAD and SCZ groups than in the other two groups (each P = 0.045).
The quality of decision-making of CGT was significantly lower in the SAD group than normal when the red and blue box ratio was 9:1 (P = 0.0031) and 8:2 (P = 0.01) [Figure 3]. SCZ patients also have an inferior quality of decision-making than normal at a 6:4 ratio (P < 0.001). BPAD patients scored poorly in quality of decision-making at 9:1 compared with normal controls (P = 0.04). Although choice latency (decision speed) of descending series was not statistically different across the four groups (F = 0.96, P = 0.42), the SCZ group had prolonged choice latency in ascending series compared to the normal control (P = 0.02) [Figure 3].
Figure 3.
Line graph showing quality of decision making (QDM) based on CGT among four groups of patients
SAD patients placed fewer bets (in percentage) than their SCZ counterparts at 9:1 (P = 0.03) and 7:3 (P < 0.01) ratios of ascending series. BPAD, in turn, had a lower percentage bet than SCZ at 8:2 and 7:3 ratios of ascending series (P = 0.01 and 0.02, respectively) [Figure 4]. Conversely, the SAD group at a 6:4 ratio and the SCZ group at a 9:1 ratio betted significantly less percentage than their BPAD counterpart (P = 0.03 and P = 0.04, respectively). Normal participants, in both ascending and descending series, and the bipolar group, only in ascending series, had gradually reduced their percentage of bets, as they passed through higher probability to lower probability (i.e. 9:1 to 6:4 ratio) [Figure 5]. Thus, the benefit of bet in higher probability is better recognized by BPAD and NC participants than SAD and SCZ patients.
Figure 4.
Line graph showing risk adjustment in ascending series of CGT among four groups of patients
Figure 5.
Line graph showing risk adjustment in descending series of CGT among four groups of patients
DISCUSSION
The present study was conducted in a dedicated psychology laboratory with the motivation to investigate if SAD is a separate entity from SCZ and BPAD from the viewpoints of executive function and clinical parameter.
Executive functions in three psychotic groups and normal controls: More impairment in most of our neuropsychology domains has been found in psychotic patients than in normal controls, which is consistent with some previous studies.[4,7] The results of the present study also found similar deterioration in stable SAD, SCZ and psychotic BPAD participants in some other executive functions. Further in this section, we have discussed whether SAD patients share some of the deficits in executive functions with SCZ and psychotic BPAD patients.
Executive function results when compared among four groups. We found that all psychotic patient groups had impairment in attentional control, attentional flexibility, spatial working memory, visuo-motor coordination, and they made poor quality decisions compared to normal participants. Thus, it can be inferred that any of these three psychoses can impair the underlying neuronal mechanisms for executive functions similarly.[16,17,18]
In comparison to psychotic BPAD SAD patients, who depicted weaker attention control capacity, so that they took more time to complete the trail making and read colored words. Many recent authors supported our findings by their dependent variables like TMT latency[8] and digit symbol,[4] but some other authors[19,20] contradict this finding (i.e., equal deficits in attentional control measured by the TMT and SCWT).
Our SAD patients also showed poor directed attention because they took extra time and dedicated extra cognitive effort to discard irrelevant but salient information (verbal) in favor of less obvious aspects (color naming) of SCWT. They additionally showed impaired cognitive set shifting compared to bipolar patients. This provides a guess that our SAD patients had poorer learning capability from the environmental reactions. Moreover, we saw that SAD patients (as also our SCZ patients) could utilize directed attention less competently, and had worse cognitive set shifting than our normal participants. Simonsen et al.[4] found equal impairment of cognitive interference in both the SCZ and SAD groups. In line with our findings, Torrent et al.[8] also reported greater impairment in euthymic SAD patients than BPAD patients as to the Stroop interference of SCWT. Many of the previous studies using WCST[21,22] and (D-KEFS)[4] concluded that SCZ and SAD patients perform equally to bipolar patients in maintenance of set and response to feedback.
SAD patients were as capable as psychotic bipolar patients in choosing, evaluating and rejecting or adopting alternative courses (i.e., planning ability and strategy and concept formation), which shows that they may have some similar deficits in underlying neuronal mechanisms. However, among the four groups, SCZ had the lowest ability for planning and strategy formation, and cognitive set shifting. However, our SAD patients made their decision less efficiently than SCZ patients in the gambling task, especially when the red-to-blue box ratio was most favorable. Hooper et al.[5] controlling for age, establishes no significant differences between SCZ and SAD in problem-solving efficiency. On the contrary, Roofeh et al.[9] and Goldstein et al.[23] using the Wisconsin Card Sorting Test (WCST) found no group differences for first-episode SCZ and SAD patients in the domain of organizational strategies.
The offering of bets in both ascending and descending conditions provided us an opportunity to understand whether the decision-making behavior was based on impulsivity or risk-taking. But both SAD and SCZ patients could not follow this concept of need for a reduction of the percentage of bet, as they passed through higher probability to lower probability ratios (i.e., 9:1 to 6:4) to score more in CGT. So they became more impulsive and took high risks. Thus, the benefit of bet in higher probability is better recognized by BPAD and NC participants than SAD and SCZ patients.
Sociodemographically, unemployment was significantly higher in SCZ participants (47.8%) than in the other two psychotic groups (30.4% each) and in the normal control group (21.7%).
Clinically, the SAD group had a significantly longer duration of current episode as compared to the psychotic bipolar group, but shorter than the SCZ group. Most previous studies described a general impairment that differs from that of chronic patients only in degree.[24] Both the duration of active psychosis and the duration of untreated psychosis were prolonged in our SAD and SCZ group compared to the psychotic bipolar group. Although it was related to some of the neuro-psychological variables like the number of SOC problems solved and IED errors, it had no significant influence on group differences. Our SAD patients were treated with significantly higher doses of antipsychotics than psychotic bipolar patients. Family history of affective disorder was more prevalent in SAD and BPAD patients. Non-affective psychotic disorders in their families were equally (4.3%) reported by both SAD and SCZ patients. Thus, clinically and demographically, SAD patients shared features of both SCZ and BPAD.
Limitations
Notwithstanding the present study’s attempt to improve upon the methodological shortcomings of earlier studies, it is also not free from limitations. The present study did not use any structured diagnostic interview for confirmation of diagnosis. Secondly, the participants were assessed when they were clinically stable, so the findings cannot be generalized to more symptomatic patients. Moreover, it is also not clear how well the results may generalize to schizoaffective patients with a less favorable response to treatment. A small sample of our cohort and the non-prospective nature of our study limit interpretation in terms of causal associations between predictors and outcome. Rural urban distribution difference between psychotic and normal control could be a confounder for some of the results. Future studies can be framed to ascertain if tests like SCWT (especially CW score and Stroop interference) and SWM (especially error score) can be utilized to differentiate SAD from BPAD patients. Future research can also be conducted in SAD patients to correlate morphologically with significant gradient features of fronto-temporal regions, hippocampus, and insula, as studied by Hung et al.[25] in their SCZ patients. Lastly, one may go for executive functioning in subsections of these psychotic patients who have suicidal ideation or recent suicidal attempt, as done by Verma et al.[26]
CONCLUSIONS
Keeping in mind the above-mentioned limitations of this study, psychiatrists and psychiatry residents may look for CW score, Stroop interference and SWM errors to differentiate SAD patients from BPAD as an additional tool in only selected clinically confusing cases. In addition to clinical features elicited by the psychiatrists in their clinics, the percentage bet placed in different probability ratios in CGT may be of help to differentiate SAD and SCZ patients from BPAD patients. However, because of the limitations, there is weak generalizability of these findings when used in clinics.
Declaration regarding the use of generative AI
Here, all authors affirm that there was no use of generative artificial intelligence (AI) technology in the generation of text, figures, or other informational content of this manuscript. We assume full responsibility for the entire content of the manuscript, and no part of it was generated by the AI tool.
Conflicts of interest
There are no conflicts of interest.
Diagram for the flow of participants
Acknowledgments
We thank Dr. S Haque Nizamie, Dr. D Ram and Dr. B Das, Ex-directors, CIP; Dr. Nishant Goyal, Professor, CIP; Dr. Devvarta Kumar, Professor (clinical psychology), NIMHANS, Bangalore, for their cooperation during the whole journey of this project. A special thank to Ms Swarnrekha for her patience and help while writing the manuscript. We assume full responsibility for the entire content of the manuscript, and no part of it was generated by the AI tool.
Funding Statement
Nil.
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Associated Data
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Supplementary Materials
Diagram for the flow of participants