OBJECTIVE: This study aimed to investigate thalamic shape alterations and their relationships with various episodic memory impairments in subjects with amnestic mild cognitive impairment (aMCI). METHODS: We compared volumes and morphological alterations of the thalamus between aMCI subjects and healthy controls. In addition, we investigated the correlation between thalamic deformations and various memory impairments in aMCI subjects using a comprehensive neuropsychological battery. RESULTS: The normalized left thalamic volumes of the aMCI group were significantly smaller than those of the healthy control group (p<0.0001). aMCI subjects exhibited significant thalamic deformations in the left thalamic dorso-medial and antero-medial areas compared with healthy individuals. CERAD-K Word List Memory scores were significantly correlated with the left dorso-medial areas in aMCI subjects. There were no significant correlations between verbal fluency, Boston naming test, constructional praxis, Word List Recognition, and Visuospatial Recall scores and thalamic shape in aMCI subjects. Verbal delayed recall scores were also significantly correlated with the left dorso-medial areas in the aMCI group. CONCLUSION: Structural alterations in the thalamic deformations in the left dorso-medial and antero-medial areas might be core underlying neurobiological mechanisms of thalamic dysfunction related to Word List Memory and delayed verbal recall in individuals with aMCI.
Cognition ; Memory ; Memory, Episodic ; Mild Cognitive Impairment* ; Thalamus

OBJECTIVES: Previous studies have shown that bilateral eye movements enhance episodic memory retrieval. However, few studies on the effect of bilateral eye movements on emotional memory have been reported. Therefore, this study was conducted in order to investigate the differences in memory retrieval between neutral and angry stimuli after bilaterally alternating eye movements. METHODS: Twenty seven healthy right-handed subjects participated in this study. The participants learned faces (angry or neutral face), and then performed a recognition memory task in relation to the faces after bilateral eye movements and central fixation. Recognition accuracy, response bias, and mean response time to hits were compared and analyzed. Two-way repeated measure analysis of variance was performed for statistical analysis. RESULTS: There was a significant effect of bilateral eye movement conditions in recognition accuracy (F=13.833, p<0.01). Statistically significant interaction effects were observed between eye movement condition and face emotion type (F=6.253, p=0.02). CONCLUSION: In this study, recognition memory for angry faces was more enhanced than that for neutral faces after bilateral eye movements. This finding suggests that bilateral eye movements can improve recognition memory for emotional stimuli more than that for neutral stimuli.
Bias (Epidemiology) ; Eye Movements* ; Memory* ; Memory, Episodic ; Reaction Time

OBJECTIVES: Previous studies have shown that bilateral eye movements enhance episodic memory retrieval. However, few studies on the effect of bilateral eye movements on emotional memory have been reported. Therefore, this study was conducted in order to investigate the differences in memory retrieval between neutral and angry stimuli after bilaterally alternating eye movements. METHODS: Twenty seven healthy right-handed subjects participated in this study. The participants learned faces (angry or neutral face), and then performed a recognition memory task in relation to the faces after bilateral eye movements and central fixation. Recognition accuracy, response bias, and mean response time to hits were compared and analyzed. Two-way repeated measure analysis of variance was performed for statistical analysis. RESULTS: There was a significant effect of bilateral eye movement conditions in recognition accuracy (F=13.833, p<0.01). Statistically significant interaction effects were observed between eye movement condition and face emotion type (F=6.253, p=0.02). CONCLUSION: In this study, recognition memory for angry faces was more enhanced than that for neutral faces after bilateral eye movements. This finding suggests that bilateral eye movements can improve recognition memory for emotional stimuli more than that for neutral stimuli.
Bias (Epidemiology) ; Eye Movements* ; Memory* ; Memory, Episodic ; Reaction Time

Although delusion of theft (DT) is the most frequent type of delusion in Alzheimer's disease (AD), its relationship to cognitive functions remains unclear. The aim of this study was to demonstrate the relationship between DT and cognitive functions in mild AD. Two hundred eighty-nine mild AD patients were enrolled in this study. These subjects were classified into three groups: patients with no delusions (ND, n=82), patients with paranoid delusions (PD, n=114) and patients with DT (n=93). Cognitive functions and their associations with the degree of delusion were compared among the three groups. The results showed that verbal Fluency scores were significantly lower in the PD group than in the DT and ND groups. Word List Recall scores were significantly lower in the DT group than in the PD and ND groups. Interestingly, delusion severity measured with the Neuropsychiatric Inventory delusion subscale correlated negatively with the Word List Recall scores in the DT group. In this study, we demonstrated that episodic memory functions in mild AD patients were associated with DT, but not with PD. Further studies might be needed to clarify the pathophysiology of delusions associated with AD.
Alzheimer Disease* ; Cognition* ; Delusions* ; Humans ; Memory, Episodic ; Theft*

Corticobasal degeneration (CBD) is a progressive neurodegenerative disorder characterized by asymmetric parkinsonism associated with apraxia, cortical sensory loss, and alien-limb phenomenon. Neuropsychological testing in patients with CBD typically shows deficits in executive functions, praxis, language, and visuospatial functioning, but not in memory. We report a CBD patient with severely impaired memory function but relatively mild motor symptoms. Detailed neuropsychological assessment showed significant verbal and visual memory deficits accompanied by frontal executive dysfunctions. Our observations indicate that CBD can in rare cases present with severe episodic memory impairment associated with frontal executive dysfunctions in the early stage of illness.
Apraxias ; Executive Function ; Humans ; Memory ; Memory Disorders ; Memory, Episodic ; Neurodegenerative Diseases ; Neuropsychological Tests ; Parkinsonian Disorders

BACKGROUND: We aimed to study the regional cerebral PET activation patterns during memory tests in medial temporal lobe epilepsy (mTLE) patients and to see whether the activation study could lateralize memory dominance. METHODS: Participants included 6 right mTLE patients, 6 left mTLE patients, and 6 controls. Language was dominant in the left hemisphere in all the participants. PETs were performed while presenting a set of 30 line drawings of com-mon objects with 4 second intervals between each drawing. After 30 minutes, PETs were repeated while presenting a set of drawings with half of the obejcts changed. RESULTS: During the encoding, activated areas were dispersed in mTLE in the superior frontal gyrus, the primary sensory cortex, the premotor area, the supramarginal and angular gyri ipsilaterally or contralaterally, in addition to the inferior and middle frontal gyri activated in the controls. During the retrieval, activated areas were localized in the bilateral inferior frontal gyri and the right medial temporal area in the controls, but also in the premotor area, the primary sensory cortex, and the angular gyrus in mTLE. In the encoding and also in the retrieval, the activated fields of the prefrontal areas contralateral to the epileptogenic zone became wider compared to the controls and those ipsilateral to the epileptogenic zone became smaller. CONCLUSIONS: Cortical areas involved in the encoding and retrieval of the episodic memory are dispersed and contralaterally lateralized to the epileptogenic zone. Lateralization is most prominent in the prefrontal areas.
Brain Mapping* ; Brain* ; Electrons* ; Epilepsy, Temporal Lobe* ; Humans ; Memory ; Memory, Episodic* ; Positron-Emission Tomography* ; Temporal Lobe*

OBJECTIVES: This study aimed to test the hypothesis that the level of current insight in patients with schizophrenia may affect autobiographical memory about their previous psychiatric history. METHODS: 28 patients with schizophrenia were interviewed with a newly designed questionnaire to report their memories about symptoms and situations during the first psychiatric admission. The subjects' memory reports were compared with their medical records. The error ratio was compared between the good and poor insight groups. RESULTS: The poor insight group demonstrated less true responses and more miss responses to the question about the existence of delusion, and more miss responses to the questions about the details of the hallucination than the good insight group. The insight level was correlated with miss ratio of the responses to questions about details of delusion. CONCLUSION: These results suggest that poor current insight in patients with schizophrenia may be related to larger distortion of autobiographical memories about certain symptoms of theirs.
Delusions ; Hallucinations ; Humans ; Medical Records ; Memory ; Memory, Episodic ; Surveys and Questionnaires ; Schizophrenia

PURPOSE: Episodic memory is described as an 'autobiographical' memory responsible for storing a record of the events in our lives. We performed functional brain activation study using H215O PET to reveal the neural basis of the encoding and the retrieval of episodic memory in human normal volunteers. MATERIALS AND METHODS: Four repeated H215O PET scans with two reference and two activation tasks were performed on 6 normal volunteers to activate brain areas engaged in encoding and retrieval with verbal materials. Images from the same subject were spatially registered and normalized using linear and nonlinear transformation. Using the means and variances for every condition which were adjusted with analysis of covariance, t-statistic analysis were performed voxel-wise. RESULTS: Encoding of episodic memory activated the opercular and triangular parts of left inferior frontal gyrus, right prefrontal cortex, medial frontal area, cingulate gyrus, posterior middle and inferior temporal gyri, and cerebellum, and both primary visual and visual association areas. Retrieval of episodic memory activated the triangular part of left inferior frontal gyrus and inferior temporal gyrus, right prefrontal cortex and medial temporal area, and both cerebellum and primary visual and visual association areas. The activations in the opercular part of left inferior frontal gyrus and the right prefrontal cortex meant the essential role of these areas in the encoding and retrieval of episodic memory. CONCLUSION: We could localize the neural basis of the encoding and retrieval of episodic memory using H215O PET, which was partly consistent with the hypothesis of hemispheric encoding/retrieval asymmetry.
Brain ; Cerebellum ; Gyrus Cinguli ; Healthy Volunteers ; Humans* ; Memory ; Memory, Episodic* ; Positron-Emission Tomography ; Prefrontal Cortex

BACKGROUND: This study was conducted to examine the effects of normal aging and cerebral pathology on the prospective memory and the relationships between the prospective memory and frontal lobe functions. METHODS: The subjects were 30 college students, 30 normal elderly, and 30 Parkinson's disease patients. There was no significant difference in the mean age or education level between the normal elderly and Parkinson's disease patients. The Cambridge Prospective Memory Test and the Prospective and Retrospective Memory Questionnaire were administered to evaluate the prospective memory. The Seoul Verbal Learning Test and Rey Complex Figure Test were given to assess the verbal and visual episodic memories. The subjects also took the Sorting Test, the Korean-Color Word Stroop Test, and the Iowa Gambling Task to assess the frontal lobe functions. RESULTS: The results showed that the prospective memory declines with aging and pathological process. The normal elderly showed significantly lower scores on the time-based prospective memory than the event-based prospective memory, although the college students and Parkinson's disease patients did not show any differences between them. Many significant correlations were found between the prospective memory tests and frontal lobe tests in the normal elderly and Parkinson's disease patients, although only a few correlations were found in the college students. CONCLUSIONS: These quantitative and qualitative changes in the prospective memory by aging and frontal lobe dysfunction would support the de-differentiation hypothesis of aging.
Aged ; Aging ; Frontal Lobe ; Gambling ; Humans ; Iowa ; Memory ; Memory, Episodic ; Parkinson Disease ; Stroop Test ; Verbal Learning

OBJECTIVE: Easy triggering of trauma-related episodic memory fragments caused by perceptual cues is tied to strong perceptual priming in the implicit memory system. And among benzodiazepines, only lorazepam has been consistently reported to have an atypical suppression effect on perceptual priming processes. The aim of this study was to investigate the effects of single doses of lorazepam, diazepam, and a placebo on intrusive memories after exposure to a distressing videotape and to explore whether the anti-intrusive effect of lorazepam is acquired as a result of the suppression of perceptual but not conceptual priming processes. METHODS: Under prospective, randomized, and double-blind conditions, we compared the anti-intrusion effect of a single dose of lorazepam (n=22) with that of diazepam (n=22) and a placebo (n=21) in young healthy Korean college students following exposure to a traumatic videotape. RESULTS: We present the first finding for an anti-intrusion effect of lorazepam. One day after the medication, lorazepam, rather than diazepam or the placebo, significantly reduced the extent of intrusion and data-driven processing of the traumatic information. There were no differences among the three conditions in state anxiety, depression, and an arousal scale throughout the experiment. CONCLUSION: Results from this study suggest the possibility of lorazepam as a candidate anti-intrusion drug, as well as the cautious use of diazepam in the treatment of PTSD patients. The anti-intrusive effect of lorazepam is directly related to its atypical inhibitory effect on implicit perceptual priming processes. The present study provides support for the enhanced perceptual priming hypothesis of PTSD.
Benzodiazepines ; Cues ; Diazepam ; Humans ; Lorazepam* ; Memory ; Memory, Episodic ; Prospective Studies ; Stress Disorders, Post-Traumatic ; Videotape Recording