Facial emotion recognition in patients with a psychotic disorder with childhood trauma

Facial Emotion Recognition in Patients with a Psychotic Disorder with

Childhood Trauma

Ruben Atteveld

Master thesis, December 22nd, 2017 Student number: 10368965

University of Amsterdam, Department of Clinical Psychology Academic Medical Centre Amsterdam

Supervisor University of Amsterdam: M. Effting, PhD

Supervisor Academic Medical Centre Amsterdam: W.A.M. Vingerhoets, PhD Word count: 6517

Index

2.5 Data Analyses and Operationalization 14

3. Results 16

Abstract

Objective: This study investigated impaired emotion recognition due to a history of childhood trauma in patients with a psychotic disorder.

Method: 25 healthy controls, 27 patients with a psychotic disorder, of whom 14 without- and 13 with a history of childhood trauma were included in this study. Childhood trauma was assessed with the Dutch version of the Childhood Trauma Questionnaire (JTV-SV). Emotion recognition was measured using the Emotion Recognition Task (ERT) from the Cambridge Neuropsychological Test Automated Battery (CANTAB).

Results: Healthy controls performed significantly better than both patients groups on the ERT (general recognition), specifically on recognition of disgust.

Conclusions: Healthy controls were significantly better in general emotion recognition than patients. Moreover, they were found to be better in recognition of disgust. These results warrant replication.

Facial Emotion Recognition in Patients with a Psychotic Disorder with

Childhood Trauma

1. Introduction

1.1 Background

Psychotic disorders are severe, psychiatric, mental disorders with a total lifetime prevalence estimated around 3.06% in the general population (American Psychiatric Association, 2000; Perälä et al., 2007). Psychotic disorders are characterized by positive symptoms such as hallucinations, delusions or thought disorders, which indicate impaired reality testing (American Psychiatric Association, 2000). Furthermore, psychotic disorders are characterized by negative symptoms such as flattening of affect and lack of motivation, but also cognitive symptoms including concentration problems, memory difficulties, impaired emotion recognition and impaired executive functioning (all together referred to as a general cognitive deficit) (American Psychiatric Association, 2000; Brüne, 2005). Research has identified numerous factors possibly contributing to the development of psychotic disorders. For example, genetic factors seem to cause a predisposition for developing psychotic

disorders (Luzi, Morrison, Powell, di Forti, & Murray, 2008). Also, heavy cannabis use greatly increases the chance of developing psychosis (Arendt, Rosenberg, Foldager, Perto, & Munk-Jørgensen, 2005; Caspi et al., 2003). Furthermore, traumatic or adverse events during childhood (sexual abuse, physical- and emotional abuse and neglect) have been related to development of psychosis later in life (Bebbington et al., 2004; Perry, Pollard, Blakley, & Baker, 1995; Read, Perry, Moskowitz, & Connolly, 2001; Read, Van Os, Morrison, & Ross, 2005). Severity of such traumatic life events has been associated with severity of cognitive symptoms in people with psychotic disorders (Kilcommons & Morrison, 2005). Childhood trauma negatively influences cognitive-, social- and brain-anatomical development (Anda et

al., 2006; Bebbington et al., 2004; Chapman, Dube, & Anda, 2007; Chartier, Walker, & Naimark, 2010; Perry et al., 1995; Read et al., 2001, 2005). Moreover, traumatic events during childhood are related to worse performance on cognitive and social tasks in healthy adults, specifically recognition of facial expression (Herba & Phillips, 2004; Majer, Nater, Lin, Capuron, & Reeves, 2010).

The ability to recognize facial emotion expression is crucial in human interactions (Guyer et al., 2007; LeDoux, 2000; cited in Knowles et al., 2015). Patients with a psychotic disorder tend to have trouble correctly recognizing facial emotional expressions (Addington & Addington, 1998; Brüne, 2005; Edwards, Jackson, & Pattison, 2002; Gessler, Cutting, Frith, & Weinman, 1989; Kohler, Walker, Martin, Healey, & Moberg, 2009). This might be because of amygdala malfunctioning, as amygdala (mal)functioning is associated with (specific) cognitive deficits in patients with a psychotic disorder (Aas et al. 2012). The amygdala is a brain area well known for its role in processing of emotional stimuli, particularly fear (Herba & Phillips, 2004; Phan, Wager, Taylor, & Liberzon, 2002; Davis & Whalen, 2001).

Amygdala functioning might be altered because of glucocorticoid-mediated transformations in the brain due to a heightened HPA-axis facilitated by experiencing traumatic events during childhood (Grant, Cannistraci, Hollon, Gore, & Shelton, 2011; Lupien, McEwen, Gunnar, & Heim, 2009; Casey, Giedd, & Thomas, 2000). Thus, it could be hypothesized that patients with a psychotic disorder who have experienced childhood trauma may have even more difficulty recognizing emotions correctly (Herba & Phillips, 2004; Majer et al., 2010).

Whether this is the case for all emotions, is unclear. Ekman (1982) hypothesized that happiness is an easier emotion to recognize compared to negative emotions such as anger, sadness and fear (Mandal, Jain, Haque-Nizamie, Weiss, & Schneider, 1999). This is because happiness is the only emotion with distinctive characteristics in facial expression, such as cheek raise, lips parting and lip corners pulling (image 1). Ekman’s hypothesis was also

investigated in cross-cultural research by Mandal (1996). North American (Canadian) and Indian subjects were both shown Caucasian and Indian faces expressing different emotions.

Both groups were found to have trouble identifying fearful and sadness expressions. Thus, in the general population Ekman’s hypothesis is established; it is more difficult to recognize anger, sadness, and fear

compared to happiness. In theory, this means that patients with a psychotic disorder (who are found to be overall cognitively impaired) would have even more difficulty to recognize anger, sadness, and fear compared to happiness than healthy subjects.

Emotion recognition might also be impaired in patients with a psychotic disorder because of information processing difficulties or biases (Addington & Addington, 1998). The idea of information processing originates from cognitive psychology, and is a term used for describing cognitive functions such as attention, perception, and short-term memory

(McLeod, 2008). Studies have found that patients with an anxiety disorder displayed altered information processing, as they stirred more attention towards fearful stimuli and were more sensitive for fearful stimuli (called a fear structure) (Foa, Feske, Murdock, Kozak, &

McCarthy, 1991; Williams, Watts, MacLeod, & Matthews, 1988; cited in Foa et al., 1991). They are expected to allocate more resources to processing information corresponding with their fears. This was also the case for traumatized rape victims (Foa et al., 1991).

Furthermore, studies on Posttraumatic Stress Disorder (PTSD) patients found altered

information processing as well, as PTSD patients direct their attention towards or away from threatening/fearful stimuli (Fani, Tone, Phifer, Norrholm, Bradley, Ressler, Kamkwalala, &

Image 1. Facial characteristics of happy expression. Source: Imotions biometric research platform, February 9th 2016.

Jovanovic, 2012; Pine, Mogg, Bradley, Montgomery, Monk, McClure, Guyer, Ernst, Charney, & Kaufman, 2005). These studies have explored and deepened the existence of a relation between trauma and emotion recognition. If this relation is cross-cutting

psychopathology remains unclear, specifically for emotion recognition impairment as

symptom of psychosis. To the best of my knowledge, studies on exploring such a relation for patients with a psychotic disorder have not yet been conducted.

Another relation that remains unclear is between the number of psychotic episodes and impaired emotion recognition. It is known that duration of a psychotic episode (before

treatment) decreases overall cognitive functioning (Scully, Coakley, Kinsella, & Waddington, 1997). Also, duration of a psychotic episode is linked to worse recovery and higher chance of relapse (Szymanski, Cannon, Gallacher, Erwin, & Gur, 1996). There have been numerous studies on childhood trauma and psychosis, which have shown a relation between childhood trauma as predictor of psychosis later in life (Bendall, Jackson, Hulbert, & McGorry, 2008; Kilcommons & Morrison, 2005). However, influence of number of psychotic episodes and childhood trauma on emotion recognition in patients with a psychotic disorder has not been investigated thus far.

This paper focuses on facial emotion recognition in patients with a psychotic disorder with a history of childhood trauma. This study attempts to investigate whether patients with a psychotic disorder with a history of childhood trauma are worse in facial emotion recognition compared to patients with a psychotic disorder without a history of childhood trauma.

Differences in facial emotion recognition between the groups might be because of altered amygdala functioning (Herba & Phillips, 2004; Majer et al., 2010). However, further

amygdala measurements were not conducted. This paper also takes a first step in exploring a fear structure in patients with a psychotic disorder with a history of childhood trauma, as studies in PTSD patients suggest emotion recognition might be altered because of traumatic

experiences. Such a structure could lead to impaired emotion recognition; suggesting that fear is recognized more often than other emotions. If this is also the case for patients with a

psychotic disorder was examined here. Furthermore, this paper explores the influence of number of psychotic episodes and childhood trauma on emotion recognition in patients with a psychotic disorder.

1.2 Hypotheses

The first objective was to investigate emotion recognition in patients with a psychotic disorder (with and without a history of childhood trauma). Based on previous research (Herba & Phillips, 2004; Majer et al., 2010), we hypothesized that both patients with a psychotic disorder with and without a history of childhood trauma perform worse on a facial emotion recognition task (happiness, sadness, anger, fear, disgust and surprise) compared to healthy controls (hypothesis 1a). In addition, it was hypothesized that patients with a psychotic disorder with a history of childhood trauma are worse in facial emotion recognition compared to patients with a psychotic disorder without a history of childhood trauma (hypothesis 1b).

The second objective is to investigate if patients with a psychotic disorder with a history of childhood trauma recognize fear better than patients with a psychotic disorder without a history of childhood trauma (hypothesis 2a). Expected is that patients with a psychotic disorder and a history of childhood trauma display a higher correct selection of the emotion fear on the facial emotion recognition task, compared to the patients without a history of childhood trauma. There was no significant expectation for the other five emotions for any of the groups. It is hypothesized that healthy controls and patients with a psychotic disorder without a history of childhood trauma are not better in specific recognition of any emotion on the facial emotion recognition task (hypothesis 2b), and are only found to differ in general emotion recognition as was outlined by hypotheses 1a and 1b.

The third objective is to investigate whether number of psychotic episodes and childhood trauma influence emotion recognition (hypothesis 3). It is hypothesized that childhood trauma and number of psychotic episodes are negatively associated with facial emotion recognition in patients with a psychotic disorder.

2. Methods

All participants gave written informed consent after the study procedure had been fully explained.

2.1 Participants

30 healthy controls and 33 patients with a psychotic disorder were examined in this study. Participants were matched on gender, age and IQ. All subjects participated in a comprehensive two-day study investigating clinical and neurobiological mechanisms underlying cognitive impairment in psychosis (abbreviated to SMURF) of the Academic Medical Centre Amsterdam (AMC). Participants, both patients and healthy controls, were recruited in several ways; by advertisement in a national newspaper, advertisements on psychosis information webpages and flyers at mental health institutes. Additionally, some participants were recruited through the Early Psychosis department at the AMC. All participants were medication free at time of participation. Participants were included when there was no physical condition, medication use or drug use present. Healthy controls with a diagnosis of a psychiatric disorder and psychotic patients with a comorbid psychiatric disorder were excluded from the study. As part of the SMURF study, all participants (both patients and healthy controls) included were administered placebo and biperiden (Akineton).

2.2 Materials

2.2.1 Comprehensive Assessment of Symptoms and History

To validate the diagnoses of all participants, The Comprehensive Assessment of Symptoms and History (CASH), which is a semi-structured interview, was administrated to assess psychotic and affective symptoms (Andreasen, Flaum, & Arndt, 1992). The CASH was also used to determine the number of psychotic episodes. It had good interrater reliability on different diagnoses (к=.78) and acceptable test-retest reliability with an average of к=.68 (Andreasen et al., 1992).

2.2.2 Positive and Negative Syndrome Scale

In this study, The Positive and Negative Syndrome Scale (PANSS) was used to determine severity of positive and negative symptoms as well as general psychopathology symptoms at time of testing. The PANSS is a semi-structured interview (Kay, Opler, & Lindenmayer, 1989) and was used to assess current positive and negative symptom severity. The PANSS consists of three scales. A Positive scale, which consists of seven items, a

Negative scale which consists of seven items, and a general psychopathology scale, consisting of 16 items. The PANSS has a total of 30 items, which were scored by experienced clinicians. A 7-point Likert-scale, ranging from Absent(1) to Extreme(7) was used for scoring. Its

internal consistency by examining correlations with socio-demographic variables, DMS IV diagnoses, clinical characteristics and drug use was acceptable and ranged from α=.70 to α=.85 (Van Den Oord et al., 2006).

2.2.3 Childhood Trauma Questionnaire

To investigate if patients have experienced traumatic events during their childhood, all participants filled out the Dutch version of the Childhood Trauma Questionnaire, called the

Jeugd Trauma Vragenlijst, Shortened Version (JTV-SV), a 25-item self-report questionnaire (Arntz & Wessel, 1996). The items of the JTV-SV are categorized by different types of trauma: Physical abuse, emotional abuse, sexual abuse, physical neglect and emotional neglect (5 questions per category). Response is rated on a 5-point Likert-scale, with a range from 1 to 5, which ranged from Never True (1) to Very Often True (5). Scale reliability was good for Physical abuse (α=.91), for Emotional abuse (α=.89), for Sexual abuse (α=.95), and for Emotional neglect (α=.91) and questionable for Physical neglect α=.63 (Thombs,

Bernstein, Lobbestael, & Arntz, 2009). Furthermore, the JTV-SV effectively discriminates clinical samples from non-clinical samples (Thombs et al., 2009). Total score on the JTV is the mean score of all 25 items (Heins, Simons, Lataster, Pfeifer, Versmissen, Lardinois, Marcelis, Delespaul, Krabbendam, van Os, & Myin-Germeys, 2011). Patients were divided in two groups based on trauma severity, which was done by using a cutoff score conducted by examining the 80th _{percentile of the total mean score on the JTV by healthy controls (Heins et}

al., 2011; van Dam et al., 2014, Varese et al., 2012). 2.2.4 Emotion Recognition Task

Emotion recognition ability was tested using the Emotion Recognition Task (ERT), which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB®) for schizophrenia. The CANTAB® is a computerized, automated neuropsychological test-battery that covers a broad range of cognitive functions such as memory, attention, executive

function, decision-making, social cognition and motor functioning. It can be used for individuals with different cultural backgrounds. Correlations between CANTAB® _subtests

and ‘’traditional’’ cognitive tests is moderate (Smith, Need, Cirulli, Chiba-Falek, & Attix, 2013). The ERT was conducted for testing social cognition (Cambridge Cognition, 2017; Russo et al., 2015). Participants finished all CANTAB® tasks in approximately 90 minutes. The ERT presents an image of a male facial expression of emotion. This emotion could be

happiness, sadness, anger, disgust, surprise or fear and also differ in intensity. The ERT presents a fixation cross, which is followed by a brief (200ms) presentation of a male facial expression of emotion. The facial expressions are followed by a mask, after which the six emotions are presented. Participant had to select by touch screen which of the six emotions had been expressed by the male facial expression. The ERT consists of two sets of 90 images with in each set, every emotion presented 15 times in different intensities. Results of the ERT are measured by correct- and incorrect. Scoring ranged from 0 (everything wrong) to 180 (everything correct), with a maximum score of 30 per emotion.

2.2.5 Wechsler Adult Intelligence Scale-III, Shortened Version

A shortened version of the Wechsler Adult Intelligence Scale-III (WAIS-III) was administrated to estimate the intelligence of the participants (Velthorst, Levine, Henquet, de Haan, van Os, Myin-Germeys, & Reichenberg, 2012). This was done for matching

participants between groups. Another reason for estimating IQ was that it was found to have a strong significant effect on emotion recognition in adolescents (Jones, Pickles, Falcaro, Marsden, Happé, Scott, Sauter, Tregay, Phillips, Baird, Simonoff, & Charman, 2011). The shortened version contained four subtests of the original WAIS-III (Information, Arithmetic, Block Design and Digit-symbol Coding) and could be completed in fifteen minutes. These subscales together represent full scale IQ (Velthorst et al., 2012). It has an overall R of .95 (R2=.92) and item-response theory on selecting items correlating highest with the original and without overlap in difficulty gave R=.96 (R2=.92). Reliability and sensitivity of IQ

resemblance were good and not significantly affected by shortening the WAIS-III (Velthorst et al., 2012).

2.2.6 Beck Depression Inventory

(estimated 50%) in patients with a psychotic disorder (Buckley, Miller, Lehrer, & Castle, 2009), the Beck Depression Inventory (BDI) was administrated to assess current depressive symptoms of the participants. Another reason to assess depressive symptoms is that depressed patients are found to perform worse on a facial emotion recognition task compared to healthy controls (Mikhailova, Vladimirova, Iznak, Tsusulkovskaya, & Sushko, 1996). The BDI has good internal consistency of α=.86 for psychiatric patients and α=.81 for non-psychiatric patients (Beck, Steer, & Garbin, 1988).

2.3 Power Analysis

A Power analysis was done by using an effect size reported in a study investigating emotion recognition in Schizophrenic subjects and healthy controls (Comparelli et al., 2013). Power analysis was done using G*Power 3 to estimate the number of participants needed (Faul, Erdfelder, Lang, & Buchner, 2007). It estimated to have 95% chance of finding an effect size of Cohen’s d=.71 (f=.355), which gave group sizes for each condition of 33

subjects per group. This Power analysis outlines the size of the healthy controls group and the patients group. This Power analysis does not provide insight on ideal group sizes for groups conducted within the patients group (with and without a history of childhood trauma). It should be mentioned that, to the best of my knowledge, no research has been conducted that has the same group distribution, same use of instruments and exact same population, which could be used as a fitting guideline for estimating Power.

2.4 Procedure

Data collection took place from March 2015 until August 2016 at the AMC. All participants underwent a urine drugs screening prior to participation (cannabis, cocaine, amphetamines and benzodiazepines). Participants were excluded when tested positive on the urine drug screening. Female participants underwent additional urine screening for pregnancy.

None of the female participants were pregnant during the study period. Participants who completed the study procedure were reimbursed.

Participants were measured twice: once after administration of placebo and once after biperiden (Akineton). Participants visited the AMC twice, once for a long day (8-12 hours) and once for a short day (6-7 hours). This was counterbalanced. The JTV-SV questionnaire and CASH interview were at all times conducted on the long day. Other questionnaires and tests were randomly conducted on the long or short day. The shortened WAIS-III was at all times conducted on the placebo day. The questionnaires, cognition test and semi-structured interview were conducted by an experienced psychologist and trained internes, who were at all times supervised by the experienced psychologist. All data used in this study was obtained after administration of placebo.

Before participants were included in the SMURF study, they were screened by telephone for psychopathology, specifically for (presence of) psychosis symptomatology and history. They were also screened for other psychiatric comorbid diagnoses. This screening determined if participants could be categorized in the non-psychopathology group (HC), or if they could be categorized in the psychotic disorder group. In this study, the psychotic disorder group is sorted into two groups based on JTV-SV scores: Patients with a psychotic disorder with a history of childhood trauma (PPDT+) and patients with a psychotic disorder without a history of childhood trauma (PPDT-), resulting in a total of three groups. To make sure participants in the HC group have indeed no psychopathology (and therefore no childhood trauma), the JTV-SV, CASH, BDI and PANSS were administered as well.

2.5 Data analysis and Operationalization

The data gathered was analyzed with IBM’s Statistical Package for the Social Sciences (SPSS), version 23. A one-way between groups ANOVA was used to check if the groups

significantly differ in IQ, age, number of psychotic episodes, current depressive symptoms and general psychopathology symptoms at time of testing. Chi-squared test was used to check if groups significantly differ in gender and ethnicity.

To investigate hypothesis 1a; whether PPDT+ and PPDT- perform worse on a facial emotion recognition task compared to HC, total correct scores on the ERT were compared. A similar approach was used to estimate difference in performance between the two groups of psychosis patients. JTV-SV scores determine presence or absence of a history of childhood trauma (see 2.2 Materials for cutoff procedure). To examine hypothesis 1a, a one way independent ANCOVA was conducted with groups as independent variable and

ERT-performance (total scores) as dependent variable. To check for confounding variables, scores on the BDI and PANSS were included as covariates. Helmert’s contrasts were used to

specifically test: 1) whether patients with a psychotic disorder (both with and without a history of childhood trauma) perform worse than healthy controls, and 2) whether patients with a psychotic disorder with a history of childhood trauma perform worse than patients with a psychotic disorder without a history of childhood trauma (hypothesis 1b) (Field, 2013).

To investigate hypothesis 2a and 2b; whether PPDT+ recognize fear better than PPDT- and HC on a facial emotion recognition task, total correct fear selection was compared

between groups. Furthermore, all other emotions (happiness, sadness, anger, disgust and surprise) were also tested between groups. A MANOVA was conducted on all emotions, but for only one of the emotions (fear) a hypothesis was formed. As little is known about

recognition of the other five emotions in patients with a psychotic disorder (with and without a history of childhood trauma), these were also analysed. Groups were the independent variables and correct emotion selections on the ERT (per emotion category) were the dependent variables.

To investigate hypothesis 3; whether number of psychotic episodes and childhood trauma influence impaired emotion recognition, a multiple regression analysis was done on number of psychotic episodes, JTV-SV scores (both predictors), and total correct scores on the ERT (independent variable). Impaired emotion recognition was measured by total correct response on the facial emotion recognition task and number of psychotic episodes was registered as part of the CASH interview. Only PPDT- and PPDT+ were analysed as HC did not experience any psychotic episodes.

3. Results

3.1 participant characteristics

Five healthy controls (HC) and six patients with a psychotic disorder (PPD) were excluded due to early dropout or incomplete data. Descriptive statistics are displayed in table 1. Mean and SD of HC scores on the JTV-SV were M = 1.46, SD = .39. The 80th percentile of the mean of HC scores on the JTV-SV was 1.64, and was therefore used as a cutoff score to divide the patients with a psychotic disorder condition into two groups (PPDT- and PPDT+).

Analyses showed groups did not significantly differ in gender, with χ2 (2) = 332, p = .85, but assumptions on sample sizes were violated. Therefore, likelihood-ratio was analyzed (Field, 2013) which yielded χ2 _{(2) = .338, p = .85. Groups differed significantly in ethnicity,}

with χ2 (4) = 10.710, p = .03. A one-way between groups ANOVA was conducted to check if groups significantly differed in IQ, age, number of psychotic episodes, current depressive symptoms (BDI) and general psychopathology symptoms (PANSS). Assumption of homogeneity of variances as tested by Levene’s F test was violated for current depressive symptoms measured by the BDI (F(2, 49) = 6.054, p < .01) and general psychopathology symptoms measured by the PANSS (F(2, 49) = 8.154, p < .01). Therefore, these variables were included as covariates in further analyses. Groups did not significantly differ on age, IQ

or number of psychotic episodes (table 1). Table 1

Descriptive statistics for HC, PPDT-, and PPDT+.

PPD HC N = 24 PPDT- N = 14 PPDT+ N = 13 Gender M/F 16/9 10/4 8/5 Ethnicitya _{(N, %)} • Caucasian • African-American • Asian • Other Diagnosis • Schizophrenia* o Paranoid o Undifferentiated • Schizophreniform disorder • Schizoaffective disorder • Psychotic disorder NOS 25(100%) - - - 10(72%) 2(14%) - 2(14%) 3(22%) - 1(7%) 2(14%) 8(57%) 8(62%) 2(15) - 3(23%) 4(31%) 3(23%) - 1(8%) 5(38%) M ± SD M ± SD M ± SD Age 25.21 ± 4.65 27.38 ± 3.99 28.06 ± 6.14 IQ 106.48 ± 16.22 101.14 ± 17.09 98.31 ± 12.64 BDIb _{4.56 ± 5.88 12.29 ± 12.52 12.54 ± 11.28} PANSSc _{17.00 ± 3.69 22.43 ± 6.96 24.00 ± 6.48} JTV-SV 1.46 ± .39 1.41 ± .16 2.22 ± .49

No. of psychotic episodes 1.21 ± .43 1.15 ± .38

*Schizophrenia subtypes as diagnosed with the Comprehensive Assessment of Symptoms and History. a _{= p < .05 for HC vs. PPDT-, HC vs. PPDT+, PPDT- vs. PPDT+.}

b _{= p < .05 for HC vs. PPDT-, HC vs. PPDT+, PPDT- vs. PPDT+.} c _{= p < .05 for HC vs. PPDT-, HC vs. PPDT+, PPDT- vs. PPDT+.}

3.2 General emotion recognition

To test hypothesis 1a, a One-Way ANCOVA was performed to examine group

differences in performance on the ERT while controlling for IQ, current depressive symptoms and general psychopathology symptoms which gave F(2, 46) = 3.527, p = .04. A first contrast showed that HC scored significantly better on the ERT compared to PPD, with p = .03. A second contrast, to test hypothesis 1b, did not yield a statistically significant difference on ERT performance between PPDT- and PPDT+ (p = .15). Mean scores on total correct ERT performance

per group are displayed in figure 1. 3.3 Specific emotion recognition

Before testing hypothesis 2, selection of the separate emotions was checked for normal distribution per group using Shapiro-Wilk’s test for normality, which is commonly used for testing normal distribution in small samples (Field, 2013). Analysis showed that emotion selection was normally distributed for all groups except surprise for HC, with D(25) = .828, p < .01. Analyzing skewness for surprise in HC gave z = -3.56, p < .01 meaning surprise was significantly skewed to the right (Field, 2013).

To see if there was a difference between HC and PPD (PPDT- and PPDT+) in

recognition of fear, a MANOVA was conducted on all emotions except surprise, as it was not normally distributed. Box’s test of equality of covariance matrices assumption was not

violated. No significant differences were found for HC and PPD on recognition of fear with Figure 1. Mean total correct ERT scores per group.

HC PPD T-PPD T+ 0 50 100 150

F(2, 46) = 1.102, p = .34, happiness with F(2, 46) = 2.157, p = .13, sadness with F(2, 46) = 1.138, p = .33 and anger with F(2, 46) = .315, p = .73. HC were found to significantly recognize disgust better than PPD, with F(2, 46) = 5.8889, p < .01. A first contrast using Helmert’s contrast found HC significantly recognize disgust better than PPD (p < .01). A second contrast using Helmert’s contrast found no significant difference within PPD (between PPDT- and PPDT+), which yielded p = .91. As recognition of surprise was not normally distributed, a Mann-Whitney test was conducted which yielded U 281.000, z = -1.04, p = .29 which found HC and PPD did not significantly differ in recognition of surprise. Mean scores for correct selection on each emotion per group are displayed in figure 2.

These analyses found that both patients with a psychotic disorder with and without a history of childhood trauma were worse at recognizing disgust compared to healthy controls. There were no significant differences in recognition in any of the separate emotions between the two groups of patients with a psychotic disorder.

Figure 2. Mean scores for correct selection on each emotion per group.

happiness sadness anger fe ar disgust surprise 0 10 20 30

times correct on ERT

HC PPDT-PPDT+

3.4 Number of psychotic episodes on emotion recognition

A multiple regression was conducted to examine hypothesis 3; whether number of psychotic episodes and experience of childhood traumatic events influence emotion

recognition. No assumptions were violated. JTV-SV scores were not used as a dichotomous variable for distinguishing two groups, but as continuous variable indicating levels of trauma experience. A non-significant regression equation was found F(2, 24) = .93, p = .41, with R2=.07 (∆R2 = -.005) for number of psychotic episodes and JTV-SV scores on ERT total correct scores. Number of psychotic episodes was not a significant predictor for ERT total correct scores, with b1= 7.683, t = .83, p = .42. JTV-SV was also not a significant predictor for ERT total correct scores, with b1 = -6.018, t = -.89, p = .38. Number of psychotic episodes and experience of traumatic events during childhood were not found to be of significant influence on emotion recognition.

4. Discussion

In this study the relation between emotion recognition and history of childhood trauma in patients with a psychotic disorder was investigated. In line with previous studies, patients with a psychotic disorder performed significantly worse on an emotion recognition task compared to healthy controls (Addington & Addington, 1998; Edwards et al., 2002; Kohler et al., 2009). No significant difference in performance on the emotion recognition task was found between patients with a psychotic disorder with and without a history of childhood trauma. In addition, it was found that psychotic patients with and without a history of

childhood trauma had significantly more difficulties correctly identifying disgust compared to healthy controls. However, no significant difference in recognition of disgust was found between patients with a psychotic disorder with and without a history of childhood trauma. No significant differences were found between healthy controls and patients with a psychotic

and surprise. Concluding, the present study found patients with a psychotic disorder to be worse in emotion recognition than healthy controls, specifically for recognition of disgust.

The lack of difference in fear recognition between patients with a psychotic disorder with and without a history of childhood trauma suggests absence of a so called fear structure in patients with a psychotic disorder and childhood trauma, even though earlier studies on PTSD found presence of such a fear structure (Foa et al. 1991). In theory, this might be because patients with a psychotic disorder are found to be generally cognitive impaired (American Psychiatric Association, 2000; Brüne, 2005), which might have influenced their way of emotion recognition. Hypothetically, it could be there used to be a fear structure present, developed due to traumatic experiences during childhood, but this fear structure became ‘masked’ by impairment in emotion recognition caused by psychosis. This might be an interesting topic of further investigation, which could be implemented in longitudinal studies in ultra high risk (UHR) patients measuring emotion recognition.

No significant difference was expected on any of the other emotions than fear.

However, it turned out that in this study healthy controls significantly differed on recognition of disgust. Literature on research on recognition of disgust found, that in order to understand this facial expression, one must feel some form of disgust (Wicker, Keysers, Plailly, Royet, Gallese, & Rizzolatti, 2003). Furthermore, Wicker et al. (2003) found the insula to be the neural basis of seeing and feeling disgust. Moreover, patients with a psychotic disorder were found to have grey matter reduction in the (bilateral) insula (Palaniyappan, Balain, & Liddle, 2012). In line with these studies, it could be hypothesized that patients with a psychotic disorder have an underdeveloped sense of feeling disgusted because of structural changes in the insula. This might be an interesting topic of further research. Another explanation might be that patients with a psychotic disorder tend to misinterpret disgust for another emotion, as was found for patients with a social anxiety disorder and non-anxious individuals (Heuer,

Lange, Isaac, Rinck, & Becker, 2010). In that study, social anxious subjects were found to misinterpret disgust for contempt, while non-anxious individuals interpreted disgust as happiness. While contempt is not an emotion measured with the ERT, it is noteworthy that disgust might be misinterpreted for another negative emotion, as contempt is seen as a combination of anger and disgust (TenHouten, 2006). This is in line with Ekman’s (1982) theory and earlier research by Mandal (1996) and Mandal et al. (1999), stating it is more difficult to distinguish between negative emotions (sadness, anger, fear, disgust), than negative from happy emotions (e.g. happiness vs. sadness). Nonetheless, Heuer et al. (2010) also found that disgust is also misinterpreted for a positive emotion, suggesting it seems to be difficult to correctly interpret facial expression of disgust. If this is the case for other

psychiatric disorders is unknown. This could be an interesting topic of further research. A limitation was that in this study no analyses on misinterpretation have been conducted, as there was no data on what emotion was selected when not selecting the right emotion.

Although the present study indicates there might be some interpretation difficulties for disgust in patients with a psychotic disorder, this needs to be investigated further.

Nonetheless, with the present study, a first step is taken in exploring the role of childhood trauma in interpretation of emotion in patients with a psychotic disorder.

Moreover, no conclusion can be drawn on information processing or attention

allocation, as the facial emotion recognition task used in this study does not register time from presentation of stimulus until answer selection. This task only registers right or wrong

emotion selection. If significant differences in response time were found, as was stated by Foa et al. (1991), this would provide more insight in information processing in patients with a psychotic disorder with a history of childhood trauma. However, it might be hypothesized that emotions that were correctly selected compared to other emotions per group point in the

direction of possible altered information processing. Further research, with aforementioned implementation of response time measurement registration might strengthen this hypothesis.

Explorative analysis on a possible effect of number of psychotic episodes on trauma severity and emotion recognition did not implicate a significant effect. Earlier studies found that as duration of psychotic episodes increased, cognitive functioning decreased (including emotion recognition) (Scully et al., 1997). According to the present study, number of

psychotic episodes is not a significant moderator of emotion recognition. However, duration of psychotic episodes was not registered in this study, thus complicating direct comparison with results reported by Scully et al. (1997).

Findings described in the present study are not in line with previous studies

investigating the role of childhood trauma in development of psychotic disorders and emotion recognition. This discrepancy in findings might be due to differences in measurement of traumatic events. For example, in this study, participants are classified as having no history of childhood trauma, or having a history of childhood trauma based on JTV-SV scores. Even though this way of classifying participants into two groups has been used before (Heins et al., 2011; van Dam et al., 2014; Varese et al., 2012), it might not be the most optimal way to do so. Using this method, someone with a traumatic experience such as one experience of sexual abuse (e.g. rape) could be classified as no history of childhood trauma, as their JTV-SV score would be under the cutoff score. On the other hand, if someone scored ‘sometimes true’ on all items, their score would be above the cutoff score. Intensity of traumatic experiences in this case is lower than previous example about rape, but as it is on multiple subcategories within trauma (physical neglect, emotional neglect, physical abuse, sexual abuse, emotional abuse) the total score is higher, compared to someone who only scores high on one subcategory (sexual abuse). In other words, according to the JTV-SV trauma severity is higher in the latter case compared to the earlier example. It could however be that a participant with a higher

score (who is assigned to the history of childhood trauma group) has in fact less emotional distress because of their traumatic experiences (type 1 error) than another participant

(assigned to the no history of childhood trauma group), who has a lot of severe symptoms but experiences a single intense traumatic event (type II error). Intensity of traumatic experiences as well as resilience plays an important role in severity, but is not adequately measured with the JTV-SV. JTV-SV focuses on frequency of experiencing traumatic events, which is not an objective way for measuring intensity.

In addition, the JTV-SV has no items on experience of single traumatic events, such as sudden death of a loved one, which can be traumatizing. Such single events are found to be potentially traumatic (Carlier, Voerman, & Gersons, 2000). In the Dutch population, more than half of the population (53.9%) experienced such a single event in their life (de Vries, & Olff, 2009). In the present study, participants might have been differently categorized if measurements on such single events were also taken into account.

Furthermore, resilience is not taken into account when using the JTV-SV. How one experiences an event influences if it is perceived as traumatic. Previous research found that lifetime prevalence of witnessing potential traumatic events in the Dutch population was 80.7%, while in the same population lifetime prevalence of developing PTSD was 7.4% (de Vries, & Olff, 2009). This means that although a majority of the population encounters events that could be traumatic, in only a small percentage this leads to psychopathology. The JTV-SV assumes registered events are perceived as traumatic, while this might very well not be the case.

Another limitation of this study is the use of the Emotion Recognition Task. Although the ERT is a well-validated task, it might still be possible that participants did not perform to their maximum potential. This could be due to several reasons. First, the ERT was

finished nine different tasks, al testing cognitive functioning. These tests altogether usually took approximately 60 minutes to complete. Therefore, when starting with the ERT

participants might have been tired and lost concentration, which could have influenced the results. Secondly, the ERT shows stimuli very briefly (200ms), which might be too quick for psychotic participants to see and interpret, as they report cognitive impairment (such as attention or concentration) (Addington & Addington, 1998; Brüne, 2005; Herba & Phillips, 2004; Majer et al., 2010). Furthermore, static presentation of facial emotion expressions (e.g. pictures, as used by the ERT) might not be the most effective method of measuring emotion recognition (Wehrle, Kaiser, Schmidt, & Scherer, 2000). Dynamic facial emotion expression (e.g. a short video), were more accurately recognized than static expressions (far better than chance rates), while confusion rates on emotion recognition were reduced (Wehrle et al., 2000). Therefore, participants in this study might not have reached their potential in emotion recognition, as the ERT does not use the most effective method of measuring emotion recognition.

Moreover, there might be some placebo effect. In the SMURF study, in which data used in the present study was obtained, all participants were single blind and took both biperiden (Akineton) and a placebo pill. It could be participants thought they took the biperiden (while they were administered the placebo pill) and therefore behaved differently, as if they were experiencing side effects. This might have influenced the results. Although in this study only data was used when participants were on the placebo, an effect might not be ruled out.

Furthermore, in this study a small sample was analyzed. With a total N = 51, divided over three groups (HC N = 25, PPDT- N = 14, PPDT+ N = 13), sample sizes needed for healthy controls and patient group before splitting into two groups according to the power

analysis were not reached. Power analysis resulted in a minimum of N = 33 for both healthy controls and patient group (Comparelli et al., 2013; Faul et al., 2007).

Nevertheless, a plus of the present study is all participants were medication and treatment free. Much of research done in patients with a psychotic disorder include

participants who are treated for their symptoms by therapy, medication or both. Moreover, psychotic subjects are treated with medication for a long period of time, as is indicated by current guidelines (Bosveld-van Haandel, Slooff, & Van den Bosch, 2001). In the present study there is no influence of any (antipsychotic) medication on the results.

To summarize, this study attempted to provide more insight in the relation between childhood trauma and emotion recognition in patients with a psychotic disorder. Contrary to earlier research, the present results suggest that a history of childhood trauma has no

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