Publications by authors named "Tak Hyung Lee"

Thalamocortical dysrhythmia (TCD) is a model characterized by abnormal resting-state thalamic oscillatory patterns where the alpha rhythm is replaced by cross-frequency coupling of low- and high-frequency rhythms. Although disrupted thalamic function is a suggested important pathophysiological mechanism underlying schizophrenia, knowledge regarding the TCD model in schizophrenia spectrum disorder (SSD) patients and individuals at clinical high risk (CHR) for psychosis is limited. A total of 169 SSD patients, 106 individuals at CHR for psychosis, and 105 healthy controls (HCs) underwent resting-state electroencephalography recordings.

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The symptoms of obsessive-compulsive disorder (OCD) are largely related to impaired executive functioning due to frontostriatal dysfunction. To better treat OCD, the development of biomarkers to bridge the gap between the symptomatic-cognitive phenotype and brain abnormalities is warranted. Therefore, we aimed to identify biomarkers of impaired organizational strategies during visual encoding processes in OCD patients by developing an eye tracking-based Rey-Osterrieth complex figure test (RCFT).

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Background: Although cognitive dysfunction is a core element of schizophrenia, the neurobiological underpinnings of the pathophysiology are not yet sufficiently understood. Because the resting state is crucial for cognitive functioning and electroencephalography (EEG) can reflect instantaneous neural activity, we investigated theta phase-gamma amplitude coupling (TGC) of resting-state EEG and its relationship with cognitive function in patients with first-episode psychosis (FEP) to reveal the neural correlates of cognitive dysfunction.

Methods: A total of 59 FEP patients and 50 healthy controls (HCs) underwent resting-state, eyes-closed EEG recordings and performed the Trail Making Test Part A (TMT-A) and Part B (TMT-B) and California Verbal Learning Test (CVLT).

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Objective: Although early intervention from the beginning of a psychotic episode is essential for a better prognosis, biomarkers predictive of symptomatic and functional improvement in early psychotic disorders are lacking. This study aimed to investigate whether the spectral power of resting-state electroencephalography (EEG) can be used as a predictive marker of the 1-year prognosis in patients with first-episode psychosis (FEP).

Methods: Twenty-four patients with FEP and matched healthy control (HC) subjects were examined with resting-state EEG at baseline.

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Background: Although internet gaming disorder (IGD) is considered an addictive disorder, evidence of the neurobiological underpinnings of IGD as an addictive disorder is currently lacking. We investigated whether attentional bias toward game-related stimuli was altered in IGD patients using an eye-tracking method during an anti-saccade task.

Methods: Twenty-three IGD patients and 27 healthy control (HC) subjects participated in the anti-saccade task with game-related, neutral, and scrambled images during eye tracking.

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Objective: To clarify the role of auditory P300 in predicting prognosis in patients with first-episode psychosis (FEP) during a 1-year follow-up.

Methods: Auditory P300 of 24 patients with FEP and 24 matched healthy control (HC) participants were measured at baseline. The clinical status of the FEP patients was assessed at baseline and reassessed after 1 year.

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. The reduced amplitude, prolonged latency, and increased intertrial variability of auditory P300 have been consistently reported in relation to the symptomatic severity of schizophrenia. This study investigated whether auditory P300 event-related potentials can be used as an objective indicator of symptomatic improvement by transcranial direct current stimulation (tDCS) in patients with schizophrenia.

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Obsessive-compulsive disorder (OCD) and internet gaming disorder (IGD), which are similar in that both involve repetitive behaviors and related with cognitive dysfunctions, frequently begin in early adolescence, which is a critical period for learning. Although the deterioration in cognitive functioning caused by these conditions may have adverse effects on information processing, such as text reading, there has been no comprehensive research on the objective indicators of altered reading patterns in these patients. Therefore, we evaluated eye-movement patterns during text reading in patients with OCD or IGD.

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Internet gaming disorder (IGD) is a newly identified potential addiction disorder associated with compulsive internet-game playing behavior and attentional bias toward online gaming- related cues. Attentional bias toward addiction-related cues is the core feature of addiction that is associated with craving, but the pathophysiology of attentional bias in IGD is not well-understood, such as its relationship to compulsivity. In this study, we used the electrophysiological marker of late positive potential (LPP) to compare attentional bias in IGD and obsessive compulsive disorder (OCD).

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Background: The declining transition rate to psychotic disorder and the increasing rate of nonpsychotic poor outcomes among subjects at clinical high risk (CHR) for psychosis have increased the need for biomarkers to predict remission regardless of transition. This study investigated whether mismatch negativity (MMN) predicts the prognosis of CHR individuals during a 6-year follow-up period.

Methods: A total of 47 healthy control (HC) subjects and 48 subjects at CHR for psychosis participated in the MMN assessment.

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Background: The P300 event-related potential (ERP) component, which reflects cognitive processing, is a candidate biomarker for schizophrenia. However, the role of P300 in the pathophysiology of schizophrenia remains unclear because averaged P300 amplitudes reflect both genetic predisposition and current clinical status. Thus, we sought to identify which aspects of P300 are associated with genetic risk versus symptomatic status via an inter-trial variability analysis.

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Although internet gaming disorder (IGD) and obsessive-compulsive disorder (OCD) represent opposite ends of the impulsivity and compulsivity dimensions, the two disorders share common neurocognitive deficits in response inhibition. However, the similarities and differences in neurophysiological features of altered response inhibition between IGD and OCD have not been investigated sufficiently. In total, 27 patients with IGD, 24 patients with OCD, and 26 healthy control (HC) subjects participated in a Go/NoGo task with electroencephalographic recordings.

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Hemorrhagic shock is a common cause of death in emergency rooms. Since the symptoms of hemorrhagic shock occur after shock has considerably progressed, it is difficult to diagnose shock early. The purpose of this study was to improve early diagnosis of hemorrhagic shock using a survival prediction model in rats.

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Hearing loss is one of the most common birth defects among infants. Most hearing-impaired children are not diagnosed until one to three years of age, which is too late to treat for normal speech and language development. If hearing impairment is identified and treated in its early stage, a child's speech and language skills could be comparable to his or her normal-hearing peers.

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Hemorrhagic shock is a common cause of death in emergency rooms. The objective evaluation of hemorrhagic shock is very important for early diagnosis and treatment. The purpose of this study is to understand its mechanism by analyzing the changes of bio-signals in hemorrhagic shock using controlled hemorrhage of Sprague-Dawley rats.

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