• Sleep Medicine and Psychophysiology
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• v.4 no.1
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• pp.39-48
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• 1997

Memory disorder is the most consistent neuropsychological finding in schizophrenia and seems to be a stable trait in it. It is suggested that memory dysfunction found in patients with schizophrenia is primary to biological abnormalities, not secondary to attention deficits they have. Although temporal lobe structures including hippocampus and thalamus have traditionally been thought to be implicated regions for memory disorder in schizophrenia, recent studies indicate the possibility of abnormalities in the frontal lobe and the neural circuits between brain regions. Advanced research methods such as functional imaging technique are expected to produce more detailed informations about memory function in schizophrenia.

• Anxiety and mood
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• v.8 no.1
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• pp.3-8
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• 2012

Patients with panic disoder (PD) show recollection of their first panic attack, which resembles a trauma that is perceived as an unexpected frightening and subjectively life-threatening event. Information-processing models suggest that anxiety disorders may be characterized by a memory bias for threat-related information. This paper reviews the previous researches that investigated the implicit and/or explicit biases in patients with panic disorder. Among the 17 studies, which addressed the explicit memory bias in PD patients, 11 (64.7%) were found to be explicit memory bias in PD patients. In regards to the implicit memory bias, 4 out of 9 studies (44.4%) were found to support the memory bias. The result shows that evidence of explicit memory bias in PD patients was supported by a number of previous researches. However, evidence of implicit memory bias seems less robust, thus, needs further research for replication. Also, development of new paradigms and applications of various methods will be needed in further researches on memory bias in PD patients.

• Korean Journal of Biological Psychiatry
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• v.19 no.1
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• pp.53-59
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• 2012

Objectives : Autobiographical memory (ABM) is a special type of episodic memory, containing events that have occurred in a personal life. Overgeneral tendency of ABM refers to the retrieval of memory with only general and categorical descriptions rather than specific events. ABM specificity in depression and posttraumatic stress disorder is a robust finding with relation to cognitive vulnerability, affect regulation, problem-solving ability. It is also implicated in bipolar disorder with frequent relapses. In this study, we investigated whether ABM specificity was related to manic or euthymic mood states in patients with bipolar disorder. Methods : Forty bipolar patients with manic and euthymic episodes and 25 healthy controls participated in this study. Prompted by 5 positively and 5 negatively valenced emotional cue words, each participant was instructed to recall positive or negative memories and describe them in detail. The One-way ANOVA was used to compare ABM scores and post-hoc analyses were done. Results : Comapred to the healthy persons, the bipolar patients reported significantly more general than specific negative memories in both manic and euthymic episodes (p = 0.003). However, there was no significant difference between manic and euthymic patients (p = 0.074). Conclusions : These results suggest that overgeneral tendency of negative ABM may be a trait abnormality in bipolar disorder. Moreover, this phenomenon might be related to underlying cognitive deficits or affect regulation irrespective of the mood state.

• Anxiety and mood
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• v.18 no.1
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• pp.32-37
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• 2022

Objective : Impaired working memory has been known to play an important role in the pathophysiology of obsessive-compulsive disorder (OCD) with growing evidence. Delayed matching-to-sample task (DMST) is a working memory task which have an advantage in analyzing several different working memory processes in one task. However, most of the studies have failed to reveal the working memory impairment with the DMST. The aim of this study was to identify whether working memory deficit in OCD can be evaluated with the DMST. Methods : The participants included 20 OCD patients and 20 healthy volunteers. Working memory was evaluated with the DMST with two different working memory loads. Accuracy of response and mean response time were measured. Results : OCD patients showed a significantly longer reaction time and lower accuracy in DMST compared to healthy controls in the task with high working memory loads. Moreover, the difference in accuracy showed interaction with the working memory load. Conclusion : The present results indicate that working memory deficit in patients with OCD can be evaluated with the DMST. The findings also suggest that previous negative behavioral results using the DMST were from low working memory load of the task.

• Korean Journal of Psychosomatic Medicine
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• v.4 no.1
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• pp.124-137
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• 1996

As the society becomes more industrialized and modernized, we have more chances to experience a serious traumatic event. Post-traumatic stress disorder (PTSD) has 3 major categories of symptoms such as memory disturbance, hyperarousal and avoidance or numbness. I reviewed the psychobiological evidences in 3 main categories of symptoms and the biological treatment after a brief review of the epidemiology, psychosocial etiology and diagnosis of PTSD. The memory disturbance of PTSD might be developed by the potentiation of the memory pathway mediated by norepinephrine. PTSD induces HPA axis abnormality, it might also develop hippocampal dysfunction, which might contribute to the memory disturbance. The kindling effect develops desensitization, which might develop reexperiencing of the traumatic events and hyperarousal state. Chronic aroused state of locus ceruleus with resultant chronic maladaptive state of norepinephrine system, might develop hyperarousal state. Social avoidance and physical numbing state in PTSD might be caused by serotnin or opiate system. Stress induced analgesia might be developed by opiate reliesed against the acute stress. The biologic research results would help the selective treatment of PTSD.

• Korean Journal of Biological Psychiatry
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• v.15 no.2
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• pp.92-100
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• 2008

Objectives : The purpose of this study was to investigate 1) the neuropsychological deficits with major depressive disorder(MDD) in depressed state and 2) the changes of neuropsychological dysfunctions during depressed episodes and remitted periods in the MDD group. Methods : 12 patients with MDD and 70 normal controls who were diagnosed and classified by DSM-IV and SCID-IV interview participated in this study. The psychopathology was measured using the Hamilton rating scale for depression(HAM-D) and Brief Psychiatric Rating Scale(BPRS). The memory function, executive function, and sustained attention were measured by a trained psychologist using the Korean version of Memory Assessment Scale(K-MAS), Wisconsin Card Sorting Test(WCST), and Vigilance(VIG) and Cognitrone (COG) in Vienna Test System. After 6 weeks of treatment, we retested the cognitive tests in order to measure the cognitive functions in remitted states. Results : Patients with MDD achieved significantly lower score in sentence immediately recall, verbal memory score and total memory score of the K-MAS, total errors of the WCST, response time of Vigilance and response time at "Yes" response of Cognitrone than normal controls at baseline. After 6 weeks of medication, the psychiatric symptoms in the patient group were attenuated, and most of the neuropsychological functions including attention, memory, and frontal/executive function were improved except for response time of Cognitrone. Conclusions : This study provides evidence for distinct neuropsychological deficits in patients with MDD on their depressed states and remitted periods. The impairment on response time remains after remission, and this would be a trait marker of major depressive disorder.

• The Journal of Internal Korean Medicine
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• v.34 no.4
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• pp.438-446
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• 2013

The purpose of this study is to report the clinical effects of modified Seogakjihwang-tang on a patient who had headache and memory disorder after traumatic brain injury, which were considered as the result of blood stasis. The patient had headache and memory disorder after traumatic brain injury and treated with modified Seogakjihwang-tang three times a day for 60days. As a result, the numerical rating scale and pain rating score of headache decreased and the scores of mini-mental state examination-Korea, the Korean version of Montreal cognitive assessment and the mini-memory test increased during treatment with modified Seogakjihwang-tang. Therefore, this case supports a possibility that modified Seogakjihwang-tang might be an effective treatment to patients with headache and memory disorder after traumatic brain injury.

• Korean Journal of Exercise Nutrition
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• v.15 no.4
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• pp.173-182
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• 2011

Post-traumatic stress disorder (PTSD) is a stress-related mental disorder induced by severe external stressors such as assault, disaster or severe accident. We investigated the effects of treadmill exercise on short-term memory in relation to apoptosis and cell proliferation in the hippocampus following PTSD. Stress to the pregnant rats was induced by exposure of maternal rats to the hunting dog in an enclosed room. Exposure time was 10 min, repeated three times per day, with 1 hour interval. Exposure of maternal rats to the hunting dog was continued 7 days after pregnancy until delivery. The pregnant rats in the exercise groups were forced to run on a treadmill for 30 min once a day for the same duration of stress exposure. Step-down avoidance task for short-term memory, western blot for Bcl-2, Bax, and immunohistochemistry for caspase-3, 5-bromo-2'-deoxyuridine (BrdU), and Ki-67 were conducted. Maternal rats exposed to stress during pregnancy showed short-term memory impairment. Expressions of Bax, Bcl-2, ratio of Bax to Bcl-2, and caspase-3 in the hippocampus were increased in the PTSD rats. Cell proliferation in the hippocampal dentate gyrus was decreased in the PTSD rats. Treadmill exercise alleviated short-term memory impairment and suppressed expressions of Bax, the ratio of Bax to Bcl-2, and caspase-3. Treadmill exercise also increased cell proliferation. The present results indicate that treadmill exercise alleviated PTSD-induced short-term memory impairment by suppressing apoptotic cell death and enhancing cell proliferation in the hippocampus.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.28 no.2
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• pp.123-131
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• 2017

Objectives: Executive dysfunction including working memory deficit has been suggested to be one of the major neuropsychological etiologies of attention-deficit hyperactivity disorder (ADHD). The purpose of this study was to investigate the augmentative effects of Cogmed working memory training on the symptoms and neurocognitive functions in medicated children and adolescents with ADHD. Methods: Twenty-five children with ADHD, aged 7 to 19 years, taking ADHD medication participated in this study. The participants were trained for 5 weeks with a commercially available and computerized working memory program ($Cogmed^{(R)}$) without any changes to their medication. The Korean version of the ADHD Rating Scale, Clinical Global Impression Scale, and Comprehensive Attention Test were administered before training and 4 weeks and 7 months after training, respectively. Results: After completing the training, the clinical symptoms and function, rated by the parents and clinician, were improved. In addition, the level of commission errors was significantly reduced in the selective attention (visual/auditory) task, sustained attention to response task, and flanker task. The untrained visuospatial short-term memory and working memory were also improved. These effects were still observed 7 months after the training. Conclusion: Cogmed working memory training can be a promising training option for the additional improvement of the symptoms and deficits in working memory and response inhibition in medicated children with ADHD.

• Korean Journal of Biological Psychiatry
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• v.18 no.2
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• pp.80-89
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• 2011

Pavlovian fear conditioning has been extensively studied for the understanding of neurobiological basis of memory and emotion. Pavlovian fear conditioning is an associative memory which forms when conditioned stimulus (CS) is paired with unconditioned stimulus (US) once or repeatedly. This behavioral model is also important for the understanding of anxiety disorders such as posttraumatic stress disorder. Here we describe the neural circuitry involved in fear conditioning and the molecular mechanisms underlying fear memory formation. During consolidation some memories fade out but other memories become stable and concrete. Emotion plays an important role in determining which memories will survive. Memory becomes unstable and editable again immediately after retrieval. It opens the possibility for us of modulating the established fear memory. It provides us with very efficient tools to improve the efficacy of cognitive-behavior therapy and other exposure-based therapy treating anxiety disorders.