High efficiency of left superior frontal gyrus and the symptom features of major depressive disorder / 中南大学学报(医学版)

OBJECTIVES@#Major depressive disorder (MDD) patients with anhedonia tend to have a poor prognosis. The underlying imaging basis for anhedonia in MDD remains largely unknown. The relationship between nodal properties and anhedonia in MDD patients need to be further investigated. Herein, this study aims to explore differences of cerebral functional node characteristics in MDD patients with severe anhedonia (MDD-SA) and MDD patients with mild anhedonia (MDD-MA) before and after the antidepressant treatment.@*METHODS@#Ninety participants with current MDD were recruited in this study. 24-Item Hamilton Depression Scale (HAMD-24) and Snaith-Hamilton Pleasure Scale (SHAPS) were used to assess the severity of depression and anhedonia at baseline and the end of 6-months treatment. The MDD patients who scored above the 25th percentile on the SHAPS were assigned to an MDD-SA group (n=19), while those who scored below the 25th percentile were assigned to an MDD-MA group (n=18). All patients in the 2 groups received antidepressant treatment. Functional magnetic resonance imaging (fMRI) images of all the patients were collected at baseline and the end of 6-months treatment. Graph theory was applied to analyze the patients' cerebral functional nodal characteristics, which were measured by efficiency (ei) and degree (ki).@*RESULTS@#Repeated measures 2-factor ANCOVA showed significant main effects on group on the ei and ki values of left superior frontal gyrus (LSFG) (P=0.003 and P=0.008, respectively), and on the ei and ki values of left medial orbital-frontal gyrus (LMOFG) (P=0.004 and P=0.008, respectively). Compared with the MDD-MA group, the significantly higher ei and ki values of the LSFG (P=0.015 and P=0.021, respectively), and the significantly higher ei and ki values of the LMOFG (P=0.015 and P=0.037, respectively) were observed in the MDD-SA group at baseline. Meanwhile, higher SHAPS scores could result in higher ei and ki values of LSFG (P=0.019 and P=0.026, respectively), and higher ei value of LMOFG (P=0.040) at baseline; higher SHAPS scores could result in higher ei values of LSFG (P=0.049) at the end of 6-months treatment. The multiple linear regression analysis revealed that sex were negatively correlated with the ei and ki values of LSFG (r= -0.014, P=0.004; r=-1.153, P=0.001, respectively). The onset age of MDD was negatively correlated with the ki value of LSFG (r=-0.420, P=0.034) at the end of 6-months treatment. We also found that SHAPS scores at baseline were positively correlated with the HAMD-24 scores (r=0.387, P=0.022) at the end of 6-months treatment.@*CONCLUSIONS@#There are obvious differences in nodal properties between the MDD-SA and the MDD-MA patients, such as the high ei of LSFG in the MDD-SA patients, which may be associated with the severity of anhedonia. These nodal properties could be potential biomarkers for the prognosis of MDD. The increased ei and ki values in the LSFG of MDD-SA patients may underlie a compensatory mechanism or protective mechanism. The mechanism may be an important component of the pathological mechanism of MDD-SA. The poor prognosis in the MDD-SA patients suggests that anhedonia may predict a worse prognosis in MDD patients. Sex and onset age of MDD may affect the nodal properties of LSFG at baseline and the end of 6-months treatment.

Vitamin D Deficiency/Insufficiency among Inpatients with Depressive Symptoms

OBJECTIVE: Although the association between low vitamin D levels and depressive symptoms has been widely reported, studies investigating the relationship between hypovitaminosis D and depressive symptomatology are scarce. METHODS: We retrospectively studied the relationship between vitamin D status and depressive symptoms in 196 patients hospitalized for a major depressive episode. RESULTS: The baseline 17-item Hamilton Depression Rating Scale total and depression factor (item 1, 2, 3, 7) scores were significantly higher in the vitamin-D-insufficiency/deficiency group than in the vitamin-D-sufficiency group. CONCLUSION: It is important to consider measuring the vitamin D levels of patients with severe and core depressive symptoms and providing vitamin D supplementation when necessary.

Abnormalities in Inflammatory Cytokines Confer Susceptible to Chronic Neuropathic Pain-related Anhedonia in a Rat Model of Spared Nerve Injury

OBJECTIVE: Patients with chronic neuropathic pain (CNP) have a higher incidence to develop depression. However, its pathogenesis has not yet been fully elucidated. Here we aimed to investigate the role of inflammatory cytokines in CNP-related anhedonia, which is a core symptom of depression, and to explore the effects of ketamine and parecoxib on pain and anhedonia. METHODS: A rat model of spared nerve injury (SNI) was constructed to mimic CNP. Hierarchical cluster analysis of sucrose preference test (SPT) was applied to classify the SNI rats into anhedonia susceptible and unsusceptible. Inflammatory cytokines in medial prefrontal cortex (mPFC) of brain, serum and L2–5 spinal cord were measured. Moreover, effects of ketamine or parecoxib on mechanical withdrawal test (MWT) and SPT in anhedonia susceptible rats were detected. RESULTS: Tumor necrosis factor (TNF)-α was increased in mPFC, serum and and spinal cord of anhedonia susceptible rats. Furthermore, anhedonia susceptible and unsusceptible rats both increased the interleukin (IL)-1β level in mPFC, serum and spinal cord. IL-6 was altered in serum and spinal cord, but not in mPFC. IL-10 was significantly altered in mPFC and serum, but not in spinal cord. Additionally, ketamine treatment significantly attenuated the decreased results of MWT and SPT in anhedonia susceptible rats, and that parecoxib significantly improved the MWT score, but failed to alter the result of SPT. CONCLUSION: These findings suggest that abnormalities in inflammatory cytokines confer susceptible to anhedonia in a rat model of SNI. Ketamine, a fast-acting antidepressant, has pharmacological benefits to alleviate pain and anhedonia symptoms.

Usefulness of the Patient Health Questionnaire-2 in Screening for Depression

BACKGROUND: While various screening tools are available for depression, they are not feasible in clinical practice because of their excessive number of questions. The Patient Health Questionnaire-2 (PHQ-2) consists of two questions gauging the frequency of depressed mood and anhedonia over the past two weeks. This study aimed to assess the usefulness of the PHQ-2 as a brief screening tool for depression.METHODS: This study used Korean National Health and Nutrition Examination Survey data from 2014, and the study population consisted of 4,946 individuals. We analyzed the validity of the PHQ-2 compared with ‘depression by PHQ-9,’ and obtained the optimal cut point for screening depression. The agreement between PHQ-2 and depression by PHQ-9 and the agreement between PHQ-2 and ‘currently diagnosed as depression’ were analyzed using Cohen's kappa. The correlation between EuroQol-5D (EQ-5D) index scores and PHQ-2 scores was analyzed using Student's t-test.RESULTS: Using ‘depression by PHQ-9’ as the criterion standard, PHQ-2 scores ≥2 had a sensitivity of 89% and a specificity of 87%, and a receiver operating characteristic analysis identified PHQ-2≥2 as the optimal cut point for screening. The agreement between PHQ-2 and depression by PHQ-9 was 0.430 when PHQ-2 ≥2 was used as a cut point. The agreement between PHQ-2 and ‘depression by questionnaire’ was poor. The EQ-5D index score of the depressive group was significantly lower than that of the normal group.CONCLUSION: The PHQ-2 is an effective measure for screening depression and is expected to be useful in busy clinical settings.

Anhedonia and Dysphoria Are Differentially Associated with the Risk of Dementia in the Cognitively Normal Elderly Individuals: A Prospective Cohort Study

OBJECTIVE: We investigated the impact of depressed mood (dysphoria) and loss of interest or pleasure (anhedonia)on the risk of dementia in cognitively-normal elderly individuals. METHODS: This study included 2,685 cognitively-normal elderly individuals who completed the baseline and 4-year follow-up assessments of the Korean Longitudinal Study on Cognitive Aging and Dementia. We ascertained the presence of dysphoria and anhedonia using the Mini International Neuropsychiatric Inventory. We defined subjective cognitive decline as the presence of subjective cognitive complaints without objective cognitive impairments. We analyzed the association of dysphoria and anhedonia with the risk of cognitive disorders using multinomial logistic regression analysis adjusted for age, sex, education, Cumulative Illness Rating Scale score, Apolipoprotein E genotype, and neuropsychological test performance. RESULTS: During the 4-year follow-up period, anhedonia was associated with an approximately twofold higher risk of mild cognitive impairment (OR=2.09, 95% CI=1.20–3.64, p=0.008) and fivefold higher risk of dementia (OR=5.07, 95% CI=1.44–17.92, p=0.012) but was not associated with the risk of subjective cognitive decline. In contrast, dysphoria was associated with an approximately twofold higher risk of subjective cognitive decline (OR=2.06, 95% CI=1.33–3.19, p=0.001) and 1.7-fold higher risk of mild cognitive impairment (OR=1.75, 95% CI=1.00–3.05, p=0.048) but was not associated with the risk of dementia. CONCLUSION: Anhedonia, but not dysphoria, is a risk factor of dementia in cognitively-normal elderly individuals.

Psychiatric Manifestation in Patients with Parkinson's Disease

Parkinson's disease (PD) is the second most common neurodegenerative disorder. Although its major manifestation is motor symptoms, resulting from the loss of dopaminergic neurons in the substantia nigra, psychiatric symptoms, such as depression, anxiety, hallucination, delusion, apathy and anhedonia, impulsive and compulsive behaviors, and cognitive dysfunction, may also manifest in most patients with PD. Given that the quality of life — and the need for institutionalization — is so highly dependent on the psychiatric well-being of patients with PD, psychiatric symptoms are of high clinical significance. We reviewed the prevalence, risk factors, pathophysiology, and treatment of psychiatric symptoms to get a better understanding of PD for improved management.

Fragile Self and Malevolent Others: Biased Attribution Styles in Individuals at Ultra-High Risk for Psychosis

OBJECTIVE: Biased attribution styles of assigning hostile intention to innocent others and placing the blame were found in schizophrenia. Attribution styles in individuals at ultra-high risk (UHR) for psychosis, however, have been less studied especially for its association with various psychological factors. We investigated whether UHR individuals show increased hostility perception and blaming bias and explored the associations of these biased styles of attribution with the factor structure of multifaceted self-related psychological variables and neurocognitive performances. METHODS: Fifty-four UHR individuals and 80 healthy controls were assessed by evaluating resilience, self-perception, self-esteem, and aberrant subjective experiences of schizotypy (physical anhedonia, social anhedonia, magical ideation, and perceptual aberration), basic symptoms, and carrying out a comprehensive neurocognitive test battery. Attribution styles were assessed using the Ambiguous Intentions Hostility Questionnaire. RESULTS: UHR individuals, compared with normal controls, showed increased hostility perception and blaming bias. Factor analysis of self-related psychological variables and neurocognitive performances in the entire subject population showed a three-factor solution, which was designated as reflective self, pre-reflective self, and neurocognition. Multiple regression analysis in UHR individuals revealed that hostility perception bias was associated with reflective self and composite blame bias was associated with reflective and pre-reflective self. CONCLUSION: This study supports the emergence of attribution biases in the putative ‘prodromal’ phase of schizophrenia. The associations of biased attribution styles with multifaceted self-related psychological constructs suggest that psychosocial interventions for biased attribution styles in UHR individuals should focus not only on reflective self but also pre-reflective self-related psychological constructs.

Aberrant Tendency of Noncurrent Emotional Experiences in Individuals at Ultra-High Risk for Psychosis

OBJECTIVE: This study aimed to investigate whether aberrant tendency of noncurrent emotion was present in individuals at ultra-high risk (UHR) for psychosis and to explore its associations with various clinical profiles. METHODS: Fifty-seven individuals at UHR and 49 normal controls were enrolled. The tendency of experiencing noncurrent emotion was assessed using various noncurrent emotional self-reported formats, including trait [Neuroticism and Extraversion of the Eysenck Personality Questionnaire], hypothetical (Chapman’s Revised Physical and Social Anhedonia Scales), and retrospective [Anhedonia-Asociality Subscale of the Scale for the Assessment of Negative Symptoms (SANS)] measures. Self-related beliefs (Self-Perception Scale), clinical positive and negative symptoms (SA Positive Symptoms and SANS), psychosocial function (Global Functioning Scale: Role Function and Global Functioning Scale: Social Function) were also examined. RESULTS: Subjects at UHR for psychosis reported more trait unpleasant and less trait pleasant emotions, more hypothetical physical and social anhedonia, and more retrospective anhedonia than normal controls. In UHR, self-perception was correlated to trait unpleasant emotion and hypothetical physical and social anhedonia. Negative symptoms in UHR were associated with hypothetical physical anhedonia and retrospective anhedonia. Global social functioning was related to trait pleasant emotion, hypothetical physical and social anhedonia, and retrospective anhedonia. Neurocognitive function, positive symptoms, and global role functioning were not related with any noncurrent emotional experience measures in UHR. CONCLUSION: These findings suggest that the aberrant tendency of noncurrent emotional experience may be present at the ‘putative’ prodromal phase and are grossly associated with self-related beliefs and psychosocial functioning but not neurocognitive functioning.

Influence of Anhedonia and Self-Esteem on Daily-Life Decision-Making in Patients with Schizophrenia

OBJECTIVES: Decision-making in patients with schizophrenia has been known to be inefficient in both cognitive and affective aspects. The purpose of this study was to investigate the influence of anhedonia and self-esteem on the decision-making process in schizophrenia. METHODS: Twenty patients with schizophrenia and 21 healthy controls performed the ‘apparel purchase decision-making task’, during which they were asked to respond to the preference, fitness, and price suitability, before making the final purchase decision. Generalized estimating equation and correlation analysis were conducted to explore for the difference of decision making patterns and influential factors between the two groups. RESULTS: The patients showed lower odds ratio (OR) of the fitness on the apparel purchase decision than the controls [OR 0.190 ; 95% confidence interval (CI) 0.047–0.762, p = 0.019). In the patient group, there was no correlation between the number of purchased trials and the severity of anhedonia, but the number of purchased trials was negatively correlated with the Rosenberg Self-Esteem Scale score at a trend level (R = -0.436, p = 0.055). CONCLUSIONS: Patients with schizophrenia considered the fitness of clothes less than healthy controls on apparel purchasing decisions. Schizophrenia patients with lower self-esteem were intended to buy more clothes.

Drug Abuse and Psychosis: New Insights into Drug-induced Psychosis

Addictive drug use or prescribed medicine abuse can cause psychosis. Some representative symptoms frequently elicited by patients with psychosis are hallucination, anhedonia, and disrupted executive functions. These psychoses are categorized into three classifications of symptoms: positive, negative, and cognitive. The symptoms of DIP are not different from the symptoms of schizophrenia, and it is difficult to distinguish between them. Due to this ambiguity of distinction between the DIP and schizophrenia, the DIP animal model has been frequently used as the schizophrenia animal model. However, although the symptoms may be the same, its causes are clearly different in that DIP is acquired and schizophrenia is heritable. Therefore, in this review, we cover several DIP models such as of amphetamine, PCP/ketamine, scopolamine, and LSD, and then we also address three schizophrenia models through a genetic approach with a new perspective that distinguishes DIP from schizophrenia.

Changes in tau phosphorylation levels in the hippocampus and frontal cortex following chronic stress

Studies have indicated that early-life or early-onset depression is associated with a 2- to 4-fold increased risk of developing Alzheimers disease (AD). In AD, aggregation of an abnormally phosphorylated form of the tau protein may be a key pathological event. Tau is known to play a major role in promoting microtubule assembly and stabilization, and in maintaining the normal morphology of neurons. Several studies have reported that stress may induce tau phosphorylation. The main aim of the present study was to investigate possible alterations in the tau protein in the hippocampus and frontal cortex of 32 male Sprague-Dawley rats exposed to chronic unpredictable mild stress (CUMS) and then re-exposed to CUMS to mimic depression and the recurrence of depression, respectively, in humans. We evaluated the effects of CUMS, fluoxetine, and CUMS re-exposure on tau and phospho-tau. Our results showed that a single exposure to CUMS caused a significant reduction in sucrose preference, indicating a state of anhedonia. The change in behavior was accompanied by specific alterations in phospho-tau protein levels, but fluoxetine treatment reversed the CUMS-induced impairments. Moreover, changes in sucrose preference and phospho-tau were more pronounced in rats re-exposed to CUMS than in those subjected to a single exposure. Our results suggest that changes in tau phosphorylation may contribute to the link between depression and AD.

Dandy Walker Variant and Bipolar I Disorder with Graphomania

Cerebellum is known to play an important role in coordination and motor functions. In some resent studies it is also considered to be involved in modulation of mood, cognition and psychiatric disorders. Dandy Walker Malformation is a congenital malformation that is characterized by hypoplasia or aplasia of the cerebellar vermis, cystic dilatation of the fourth ventricle and enlargement of the posterior fossa. When the volume of posterior fossa is normal, the malformation is called Dandy Walker Variant. Case is a 32 year old male with a 12 year history of Bipolar I Disorder presented with manic and depresive symptoms, including dysphoric and depressive affect, anhedonia, suicidal thoughts and behaviours, thoughts of fear about future, overtalkativeness and graphomania, increased energy, irregular sleep, loss of appetite, increased immersion in projects, irritability, agressive behavior, impulsivity. Cranial Magnetic Resonance Imaging was compatible to the morphological features of Dandy Walker Variant.

Relationship between Evaluation for the Self and others and Anhedonia in Patients with Schizophrenia / 대한정신분열병학회지

OBJECTIVES: The dysfunctional neural networks underlying self-evaluation in schizophrenia are overlapped with the neural structures involved in emotion regulation. The purpose of this study was to investigate the influence of anhedonia on the self-evaluation attitude of patients with schizophrenia. METHODS: Twenty healthy controls and twenty patients with schizophrenia performed a self-evaluation task, presenting a pair of the face (self, familiar other, and unfamiliar other) and word (negative, neutral, and positive noun) at the same time. Participants were asked to evaluate relevance between the pairs by pressing a corresponding button. Relevance rating scores were compared between the groups and were correlated with the severity of physical and social anhedonia. RESULTS: Patients evaluated the condition of a self face with a negative word and a familiar face with a negative word to be more relevant than healthy controls. In the patient group, the scores of relevance rating in the condition of an unfamiliar other face with a negative word were positively correlated with the anhedonia scale scores (physical : r=0.486, p=0.030 ; social : r=0.499, p=0.025). There was no correlation between the self-evaluation attitude and the severity of anhedonia. CONCLUSION: Patients with schizophrenia evaluate themselves badly in only negative circumstances, and anhedonia is not related to self-evaluation, but rather other-evaluation.

Protective Effects of Curcumin and Sertraline on the Behavioral Changes in Chronic Variable Stress-Induced Rats

Behavioral characteristics of the animal models and humans are impaired in chronic stress. The present study aimed to evaluate and compare the protective effects of sertraline and curcumin on stress-induced learning and memory impairment, anxiety and anhedonia in rats. Male rats were divided into seven groups: stress+water, stress+olive oil, stress+curcumin (100 mg/kg/day), stress+sertraline (10 mg/kg/day), curcumin, sertraline, and control groups. The rats were exposed to chronic variable stress for 56 days. At the end of 40 days and while the previous treatments were continued, the rats were tested in the eight radial maze, elevated plus maze, and sucrose consumption for learning and memory, anxiety, and anhedonia, respectively. In comparison to the non-stressed group, stress+water and stress+olive oil groups revealed a significantly lower percent of correct choices and higher reference and working memory errors during learning and retention phases (p<0.001). In addition these stress groups showed a significant lower percent of the open arms time and open arms entries in the elevated plus maze and consuming less sucrose solution. In addition, the stress+curcumin and stress+sertraline groups showed a better performance in the evaluated parameters of the radial arm maze, elevated plus maze, and sucrose consumption tests. It appears that curcumin and sertraline have the similar effectiveness on behavioral changes in chronic variable stress-induced rats.

Deficits in Abstract Thinking Assessed by Theme Identification in Patients with Schizophrenia / 대한정신분열병학회지

OBJECTIVES: Patients with schizophrenia often have a concrete thinking or an impairment in abstract thinking, but there has been a limitation in quantitatively measuring this cognitive function. The aim of the current study was to investigate a deficit in abstract thinking in patients with schizophrenia using the theme identification task. METHODS: Twenty subjects with schizophrenia and 20 healthy volunteers participated in the behavioral study for theme identification. The visual stimuli were composed of a series of pictures, which contained positive or negative emotional situations. Three words, indicating a main theme of the picture, a theme-related item and a theme-unrelated item, respectively, were presented in the bottom of the pictures, and participants had to select a theme. RESULTS: The patient group selected theme words at significantly lower rate in both emotional conditions than the control group (positive, p=0.002 ; negative, p=0.001). Especially, in the negative condition, the patient group more selected theme-unrelated items than the control group (p=0.001). The rates of theme identification were inversely correlated with scores of the Social Anhedonia Scale (positive, r=-0.440, p=0.007 ; negative, r=-0.366, p=0.028). CONCLUSION: Patients with schizophrenia exhibited an impairment in abstract thinking, and it was remarkable in the negative condition. The ability to think abstractly was associated with the severity of social anhedonia. The impairment of abstract thinking may become one of the reasons for poor social functioning in socially anhedonic patients.

Neuroeconomics and Psychiatry : Application of Quantitative Methodology / 신경정신의학

Neuroeconomics is an interdisciplinary field that seeks to explain human decision making using a combination of research methods from neuroscience, (behavioral) economics, and cognitive and social psychology. With recent advances in functional neuroimaging and computing power, neuroeconomics suggests the possibility of examining psychopathology using a quantitative model based on objective metrics. The purpose of this paper is to introduce the theory of neuroeconomics and to review the literature on its application to psychiatric research. First, the concept of utility function in economic decision theory can be used to explain depressive symptoms with regard to lack of interest in money. Second, differences in attitudes toward uncertainty and risk suggest that avolition and anhedonia can be expected to reduce the influence of uncertainty on decision making. Third, some parametrically varied values of delay discounting show the relation of discounted value to risk of addiction. Finally, economic game theory can provide a model including social factors to address psychiatric conditions ; thus, it provides a useful framework for the current diagnostic classification systems for consideration of interpersonal factors. We expect that conduct of more interdisciplinary research in neuroeconomics and psychiatry will clarify diagnosis and contribute to the description of psychiatric disorders.

The Reliability and Validity of the Korean Version of Apathy Evaluation Scale and its Application in Patients with Schizophrenia / 대한정신분열병학회지

OBJECTIVES: Apathy Evaluation Scale (AES) is one of the most frequently used scales to evaluate apathy. The purpose of this study was to evaluate the reliability and validity of the Korean version of the AES (K-AES) and to apply the K-AES in examining the characteristics of apathy in the Korean patients with schizophrenia. METHODS: 129 healthy people and 29 patients with schizophrenia have been evaluated using the K-AES, Physical Anhedonia Scale (PAS), Social Anhedonia Scale (SAS), and the Beck's Depression Inventory (BDI). Split-half reliability and internal consistency were evaluated and factor analysis and correlation analysis was conducted. Between-group comparison was conducted using independent sample t-tests. RESULTS: K-AES showed good reliability and validity. Factor analysis confirmed 3 factors, which represented interest and drive, initiative, self-awareness and self-assessment. Patients with schizophrenia showed significantly higher K-AES and BDI scores than the healthy group. K-AES scores in patients with schizophrenia were significantly correlated with the PAS score, but did not correlate with SAS and BDI scores. CONCLUSION: This study demonstrates the reliability and validity of the K-AES. Our findings also suggest that the K-AES may be a reliable instrument in assessing apathy as a negative symptom in patients with schizophrenia.

The Characteristics of Associative Learning of Reward Approach and Loss Aversion in Schizophrenia / 대한정신분열병학회지

OBJECTIVES: Schizophrenia patients have deficits of prediction and learning related to dopaminergic dysfunction. It is hypothesized that there would be different characteristics in associative learning of reward approach and loss aversion between controls and patients. METHODS: Participants were 23 healthy participants and 20 out-patients fulfilling criteria for schizophrenia according DSM-IV-TR. Using a monetary incentive contingency reversal task, successful learning rates, numbers of trials and errors till learning, numbers of trials of maintaining learning, response times were measured. Characteristics of learning were compared between controls and patients. RESULTS: Physical anhedonia and PANSS negative symptom scores correlated with the number of trials while loss aversion was maintained. Overall correct response rates were decreased in patient group, particularly during reward approach learning. Patients required more trials and errors to learn reward approach than controls. There were no significant differences in learning performance and reaction times between groups during loss avoidance learning. CONCLUSION: These results support previous reports of deficits in reward-driven learning in schizophrenia. However, anhedonia and negative symptoms were associated with the preserved function of loss avoidance learning.

Deficit of Executive Control of Positive Emotional Information and Its Association with Social Anhedonia in Schizophrenia / 대한정신분열병학회지

OBJECTIVES: Schizophrenia has been considered to be characterized by an abnormality in attention, especially in the executive control. Emotion is an important component of the executive control. The aim of this study was to investigate the influence of emotion on the executive control in patients with schizophrenia. METHODS: Participants were 20 healthy controls and 19 subjects with schizophrenia. They viewed full-color pictures selected from the International Affective Picture System. During each trial, an emotional picture, which was either positive or negative, lit up on either the left or right side. Participants were instructed to respond to the emotional valance of each stimulus by pressing a button with their left or right index finger, while ignoring its presented side. RESULTS: There was a group difference in the response time, and patients with schizophrenia exhibited an impairment in the executive control of emotional information. However, there was no difference in the response time between the emotional conditions. In the patient group, the missing rate in the positive emotional condition was correlated with the severity of social anhedonia, whereas the missing rate in the negative emotional condition was correlated with the severity of positive symptoms. CONCLUSION: Patients with schizophrenia have a deficit in the executive control of positive emotional information as well as negative emotion, but it may be due to different underlying mechanisms.

Deficit of Executive Control of Positive Emotional Information and Its Association with Social Anhedonia in Schizophrenia / 대한정신분열병학회지

OBJECTIVES: Schizophrenia has been considered to be characterized by an abnormality in attention, especially in the executive control. Emotion is an important component of the executive control. The aim of this study was to investigate the influence of emotion on the executive control in patients with schizophrenia. METHODS: Participants were 20 healthy controls and 19 subjects with schizophrenia. They viewed full-color pictures selected from the International Affective Picture System. During each trial, an emotional picture, which was either positive or negative, lit up on either the left or right side. Participants were instructed to respond to the emotional valance of each stimulus by pressing a button with their left or right index finger, while ignoring its presented side. RESULTS: There was a group difference in the response time, and patients with schizophrenia exhibited an impairment in the executive control of emotional information. However, there was no difference in the response time between the emotional conditions. In the patient group, the missing rate in the positive emotional condition was correlated with the severity of social anhedonia, whereas the missing rate in the negative emotional condition was correlated with the severity of positive symptoms. CONCLUSION: Patients with schizophrenia have a deficit in the executive control of positive emotional information as well as negative emotion, but it may be due to different underlying mechanisms.