1. Eosu Kim, Jeonghun Ku, Young-Chul Jung, Hyeongrae Lee, SunI.Kim, Jae-Jin Kim, Kee Nam Koong, Dong-Ho Song, Restoration of mammilothalamic functional connectivity through thiamine replacement therapy in Wernicke's encephalopathy, Neuroscience,(in press)
7. Eosu Kim, Young-Chul Jung, Jeonghun Ku, Jae-Jin Kim, Hyeongrae Lee, So Young Kim, Sun I. Kim and Hyun-Sang Cho, Reduced activation in the mirror neuron system during a virtual social cognition task in euthymic bipolar disorder, Progress in neuro-psychopharmacology & biological psychiatry, 33(8), 1409-1416, 2009.11.13
Social cognition entails both cognitive and affective processing, and impairments in both have accounted for residual symptoms of bipolar disorder (BD). However, there has been a lack of studies identifying neural substrates responsible for social cognitive difficulties in BD patients. Fourteen euthymic BD patients and 14 healthy normal controls underwent functional MRI while performing a virtual reality social cognition task, which incorporated both cognitive and emotional dimensions, simulating real-world social situations. During the scanning, subjects tried to guess (attribute) possible reasons for expressed emotion of virtual humans (avatars) while viewing their facial expressions, just after observing their verbal and nonverbal (facial) expressions which were emotionally valenced (happy, angry and neutral). BD patients compared to normal controls showed delayed reaction times in emotional conditions, with comparable response accuracy. Healthy normal controls activated the right anterior cingulate cortex, inferior frontal, and insular cortex in emotional conditions contrasted with neutral control conditions, that is, the regions that have been related to empathic processes during viewing others' emotional expression. Relative to normal controls, BD patients showed reduced activations in the ‘mirror neuron system’, including the right inferior frontal cortex, premotor cortex, and insula, mainly in angry or happy condition. These results may suggest that, even during euthymic state, BD patients have difficulties in recruiting brain regions for the utilization of emotional cues as a means for understanding others. Clinical attention should be paid to emotion-related residual symptoms to help improve social outcomes in these patients.
6. Kyung-Min Park, Jeonghun Ku, Il-Ho Park, Ji-Yeon Park, SunI. Kim, Jae-Jin Kim, Improvement in social competence in patients with schizophrenia: A pilot study using a performance-based measure using virtual reality, Human psychopharmacology, 24(8), 619-27, 2009.12.1
The objective of this study was to explore the possibility of the use of Virtual Reality Functional Skills Assessment (VRFSA) in a future regular clinical trial, as well as to report a preliminary result about effectiveness of atypical antipsychotics to social competence in schizophrenia.
We developed the VRFSA that measured subjects' performances automatically and used analogue scale rather than Likert scale. Twenty-four female patients with paranoid schizophrenia and 15 healthy females were recruited. This was a 6-week, randomized, open-label, and flexible dose study, and 2 treatments (baseline versus post-treatment) × 2 skills phases (receptive versus expressive) × 2 patient groups (aripiprazole versus risperidone) analysis of variance was used in the final analysis.
There was a significant difference in the VRFAS between the patients and the healthy subjects (p < 0.05). Eighteen patients were included in the final analysis. We found larger treatment effect than those found in previous studies, and significant treatment × skills phase × group interaction effect on the VRFAS.
Our results suggest that the VRFAS is strongly sensitive to changes in social competence and thus especially beneficial in short-term clinical trials. In addition, atypical antipsychotics can improve social competence and differentially improve receptive skills and expressive skills in schizophrenia.
5. Sung-Hyouk Park, Jeonghun Ku, Jae-Jin Kim, Hee Jeong Jang, So Young Kim, Soo Hyun Kim, Chan-Hyung Kim, Hyeongrae Lee, In Young Kim, Sun I. Kim, Increased personal space of patients with schizophrenia in a virtual social environment, Psychiatry research, 169(3), 197-202, 2009.10.30
Virtual reality may be a good alternative method for measuring personal space and overcoming some
limitations in previous studies on the social aspects of schizophrenia. Using this technology, we aimed to
investigate the characteristics of personal space in patients with schizophrenia and evaluate the relationship
between their social behaviors and schizophrenic symptoms. The distance from a virtual person and the
angle of head orientation while talking to a virtual person in a virtual environment were measured in 30
patients with schizophrenia and 30 normal controls. It was found that patients with schizophrenia had
longer distances and larger angles than did normal controls. The severity of the negative syndrome had
significant inverse correlations with the distance from the angry and neutral virtual persons and with the
angle of head orientation toward the happy and angry virtual persons, suggesting that negative symptoms
may have a close relationship with personal space, including distancing and eye gaze. The larger personal
space of patients may reflect their discomfort in close situations or cognitive deficits. Showing these profiles
to patients could help them realize the amount of personal space they need.
4. Jeonghun Ku, Jang Han Lee, Sun I. Kim, Kiwan Han, Youn Joo Kang, Eun Sook Park, Validity and Reliability of Cognitive Assessment using Virtual Environment Technology in Patients with Stroke, American Journal of Physical Medicine & Rehabilitation, 88(9), 702-710, 2009.9.1
Objectives: In this study, we aimed to assess the validity and reliability of a Virtual Environment Technology (VET)-based cognitive assessment program that was developed as a measurement tool of cognitive abilities in patients following a stroke. Design: Twenty participants diagnosed with stroke caused by unilateral brain lesions were enrolled to assess the VET program’s validity and test–retest reliability. Participants underwent evaluation by paper-based neuropsychological tests including the Korean Mini-Mental Status Examination (K-MMSE), the Korean-Wechsler Adult Intelligence Scale (K-WAIS), the Motor Free Visual Perception Test (MVPT), Rey–Kim Memory Test and Kim’s Frontal-Executive Neuropsychological Test (K-FENT) as well as the VET-based cognitive assessment. Major variables and indices of the VET program were calculated. The VET program’s validity was evaluated using a simple correlation analysis between variables from the VET program and conventional paper-based neuropsychological measurements and the reliability was evaluated by investigating the test-retest correlation coefficients. Results: Major variables and indices of the VET program in patients with stroke correlated significantly with the related scores of paper-based neuropsychological tests. In addition, the test–retest reliability analysis revealed that the correlation coefficients ranged from 0.528 to 0.926. Conclusion: The VET-based cognitive assessment program showed adequate reliability and validity as a method of cognitive assessment in patients following stroke. Key Words: Virtual Environment Technology, Stroke, Cognitive Assessment, Validity, Reliability
3. Eosu Kim, Jeonghun Ku ,Jae-Jin Kim, Hyeongrae Lee, Kiwan Han, Sun I. Kim, Hyun-Sang Cho. Nonverbal Social Behaviors of Patients With Bipolar Mania During Interactions With Virtual Humans, The Journal of Nervous and Mental Disease, 197(6), 412-418, 2009.6.1
It has been proposed that positive emotional biases could make
bipolar manic (BM) patients maintain abnormally approaching behaviors
during social interactions. To test this hypothesis, we measured interpersonal
distance (IPD) and gaze angle of BM patients and normal controls (NCs)
during social interaction in immersive virtual environment. Overall, IPDs of
BM patients (n 20) were greater than those of normal controls (n 20).
The IPD difference was even greater between NCs and BM patients with
psychotic features (n 11) than those without psychotic features (n 9).
Regardless of the presence of psychotic features, BM patients averted their
gazes more than NCs, and even more while speaking than while listening.
Our results might suggest negativistic social cognition of bipolar patients, as
was previously found even during a manic phase, or the role of paranoid
symptoms in avoidant social behaviors, in agreement with prior studies with
schizophrenic patients. Use of proper space and gaze might have psychotherapeutic
implication in developing secure, two-person relationship with
bipolar patients regardless of the presence of disrupting manic symptoms.
2. Kyung-Min Park, Jae-Jin Kim, Jeonghun Ku, So Young Kim, Hyeong Rae Lee, Sun I. Kim, Kang-Jun Yoon. Neural basis of attributional style in schizophrenia, Neuroscience Letters, 459(1), 35-40, 2009.7.31
Attributional style means how people typically infer the causes of emotional behaviors. No study has
shown neural basis of attributional style in schizophrenia, although it was suggested as a major area of
social cognition research of schizophrenia. Fifteen patients with schizophrenia and 16 healthy controls
underwent functional magnetic resonance imaging while performing three (happy, angry, and neutral)
conditions of attribution task. Each condition included inferring situational causes of an avatar’ (virtual
character) emotional or neutral behavior. In the between-groups contrast maps of the happy conditions,
the patient group compared to the control group showed decreased activations in the inferior frontal
(BA 44) and the ventral premotor cortex (BA 6), in which the % signal changes were associated with
negative symptoms. In the angry conditions, the patient group compared to the control group exhibited
increased activations in the precuneus/posterior cingulate cortex (Pcu/PCC) (BA 7/31), in which the %
signal changes were related to positive symptoms. In conclusion, patients with schizophrenia may have
functional deficits in mirror neuron system when attributing positive behaviors, whichmay be related to
a lack of inner simulation and empathy and negative symptoms. In contrast, patientsmay have increased
activation in the Pcu/PCC related to self-representations while attributing negative behaviors, whichmay
be related to failures in self- and source-monitoring and positive symptoms.
1. Park IH, Kim JJ, Ku J, Jang HJ, Park SH, Kim CH, Kim IY, Kim SI, Characteristics of social anxiety from virtual interpersonal interactions in patients with schizophrenia, Psychiatry, 72(1), 79-93, 2009.1.1
Dysfunctional emotional processing affects social functioning in patients with schizophrenia. However, the relationship between emotional perception and response in social interaction has not been elucidated. Twenty-seven patients with schizophrenia and 27 normal controls performed a virtual reality social encounter task in which they introduced themselves to avatars expressing happy, neutral, or angry emotions while verbal response duration and onset time were measured and perception of emotional valence and arousal, and state anxiety were rated afterwards. Self-reported trait-affective scale scores and the Positive and Negative Syndrome Scale (PANSS) ratings were also obtained. Patient group significantly underestimated the valence and arousal of angry emotions expressed by an avatar. While valence and arousal ratings of happy avatars were comparable between groups, patient group reported significantly higher state anxiety in response to happy avatars. State anxiety ratings significantly decreased from encounters with neutral to happy avatars in normal controls while no significant decrease was observed in the patient group. The Social Anhedonia Scale and PANSS negative symptom subscale scores (blunted affect, emotional withdrawal, and passive/ apathetic social withdrawal items) were significantly correlated with state anxiety ratings of the encounters with happy avatars. These results suggest that patients with schizophrenia have interference with the experience of pleasure in social interactions which may be associated with negative symptoms.