OBJECTIVES: This study aimed to identify the differences in the profiles of cognitive control deficits among schizophrenic patients and endophenotypes. METHODS: The study examined three groups: remitted patients with schizophrenia (n=54), unaffected first-degree relatives of the probands with schizophrenia (n=36), and a healthy control group (n=51), which were all matched for age, sex, and years of education. The AX version of the continuous performance test was used to examine cognitive control. The error rate, correct response times of each subset (AX, BX, AY, BY), and d′ as an indication of the accuracy sensitivity index were calculated. The psychopathology, intelligence, and psychomotor speed were also assessed. RESULTS: Patients with schizophrenia showed significantly poorer error rates and d′ in the AX and BX subsets than the others. They showed more delayed correct response times than the healthy control group in all subsets. The first-degree relatives also showed more delayed correct response times in the BX and AY subsets than the healthy control group, but were similar to the patients. CONCLUSION: These findings suggest that cognitive control is impaired in schizophrenia and endophynotypes possibly share this delayed information processing from the higher loading states of cognitive control.
Automatic Data Processing ; Education ; Endophenotypes ; Humans ; Intelligence ; Psychopathology ; Reaction Time ; Schizophrenia*

OBJECTIVES: This study intended to identify the deficits of cognitive control among patients with bipolar I disorder and their first-degree relatives, and identify the possibility of cognitive control as an endophenotype of bipolar disorder. METHODS: The study included three groups: euthymic states patients with bipolar I disorder (n = 55), unaffected first-degree relatives of probands with bipolar I disorder (n = 30), and a healthy control group (n = 51), that was matched on age, sex, and years of education. The AX version of the continuous performance test (CPT) was used to examine cognitive control. Error rate, correct response times of each subsets (AX, BX, AY, BY), and d' as an indication of accuracy sensitivity index were calculated. Psychopathology, intelligence, and psychomotor speed were also assessed. RESULTS: Patients with bipolar I disorder showed significantly worse error rates in the AX (p = 0.01) and BX (p = 0.02) subsets and d' (p = 0.05) than the others. They also showed more delayed correct response times than the healthy control group and first-degree relatives in all subsets (p < 0.01). But first-degree relatives showed neither high error rates nor delayed correct response times than healthy control group. CONCLUSIONS: These findings suggest that cognitive control is impaired in bipolar I disorder but less likely to be an endophynotype of bipolar I disorder.
Bipolar Disorder ; Education ; Endophenotypes ; Humans ; Intelligence ; Psychopathology ; Reaction Time

BACKGROUND: The suicide rate in Korea has been the highest among the Organization for Economic Cooperation and Development countries since 2003. However, there is a lack of in-depth data regarding the characteristics of suicide attempters. Understanding the intent of suicide attempters will help improve the effectiveness of suicide prevention strategies. Therefore, to provide a resource for developing the necessary interventions, this study aimed to examine the differences in suicide-related and clinical variables according to the strength of suicidal intent. METHODS: The subjects were 328 suicide attempters admitted to emergency departments at 5 university hospitals in Daegu-Gyeongbuk province between 2011 and 2014. We used various scales to examine suicide-related and clinical variables and a structured questionnaire to explore psychosocial characteristics. We evaluated suicidal intent using the Pierce Suicide Intent Scale and a clinician-rated scale that measured suicidal authenticity. RESULTS: Individuals with high suicidal intent were significantly older, had higher Hamilton Depression Rating Scale (HDRS) scores, higher rates of premeditation, and sustained suicidal ideation. Furthermore, suicide methods, timing, and psychiatric treatment histories differed by the strength of subjects' suicidal intent. Moreover, multiple logistic regression showed that depressed mood as a reason for attempting suicide, premeditation, and higher HDRS scores were significantly associated with higher suicidal intent. CONCLUSION: Depression, premeditation, older age, and sustained suicidal ideation were characteristics of individuals with high suicidal intent, and it is necessary to evaluate and monitor these factors to prevent repeated suicide attempts.
Depression ; Emergencies* ; Emergency Service, Hospital* ; Hospitals, University ; Intention ; Korea ; Logistic Models ; Organisation for Economic Co-Operation and Development ; Suicidal Ideation ; Suicide* ; Suicide, Attempted ; Weights and Measures