Satoshi Mochizuki

Deficits in long-term retention of learned motor skills in patients with cortical or subcortical degeneration.

We investigated the acquisition and long-term retention of new skills in patients with cortical (Alzheimers disease, AD) and subcortical (progressive supranuclear palsy, PSP; Parkinsons disease, PD) degeneration. The motor skill task performance of the PD and PSP patients improved with training, but the improvement disappeared within a few months, whereas AD patients retained learned skills for 3-18 months. The results of our experiments show that subcortical dysfunction induces a retention deficit for newly learned motor skills. Our present study suggests that a normal striatum is necessary for the formation of long-lasting motor skills, and that the striatum plays an important role as a motor skill consolidation system.

Learning-related changes of brain activation in the visual ventral stream : An fMRI study of mirror reading skill

A previous neuroimaging study has indicated that the visual dorsal stream may contribute to accurate reading of mirror-reversed words. However, the role of the visual ventral stream in the learning of mirror reading skill remains ambiguous. In the present fMRI study, we investigated learning-related changes in brain activation in the visual ventral stream in a mirror reading task. Subjects participated in three successive runs of the mirror reading task, in each of which they were asked to read mirror-reversed words and normal words as accurately and as quickly as possible. The behavioral data for the mirror reading condition showed significant improvement in reaction time but not in performance accuracy across the three runs. The activation data showed different learning-associated patterns related to the right and left visual ventral streams. On the right side, activity related to the reading of mirror stimuli was significantly greater than that related to normal stimuli in the first run only, whereas on the left side it was greater in all runs. Additional correlation analysis between response time data and percentage signal changes only in the mirror reading condition showed significant correlation on the right visual ventral stream in the first run only, whereas that on the left visual ventral stream was found only in the third run. The dissociable response between the right and left visual ventral streams may reflect learning-related changes in reading strategy and may be critical in improving the speed of reading mirror-reversed words.

Effects of self-relevant cues and cue valence on autobiographical memory specificity in dysphoria

ABSTRACT Reduced autobiographical memory specificity (rAMS) is a characteristic memory bias observed in depression. To corroborate the capture hypothesis in the CaRFAX (capture and rumination, functional avoidance, executive capacity and control) model, we investigated the effects of self-relevant cues and cue valence on rAMS using an adapted Autobiographical Memory Test conducted with a nonclinical population. Hierarchical linear modelling indicated that the main effects of depression and self-relevant cues elicited rAMS. Moreover, the three-way interaction among valence, self-relevance, and depression scores was significant. A simple slope test revealed that dysphoric participants experienced rAMS in response to highly self-relevant positive cues and low self-relevant negative cues. These results partially supported the capture hypothesis in nonclinical dysphoria. It is important to consider cue valence in future studies examining the capture hypothesis.

Elderly adults improve verbal fluency by videophone conversations: a pilot study.

Summary We conducted videophone conversations with elderly adults living in a nursing home to discover whether their verbal ability was improved by repeated remote conversations. The control group comprised five elderly adults. The experimental group comprised six elderly adults, including three patients with dementia. They took part in three videophone conversations and their verbal ability was measured before and after the conversations. During the sessions, the participants and volunteers talked about themselves and participated in a quiz. In the experimental group, the mean number of words generated increased from 4.8 to 6.5 after the session (P < 0.05); this increase was not observed in the control group. The experimental group also showed an improvement in words generated after indirect conversations. Videophone conversations appear to have some positive effects on verbal ability and may be beneficial in the cognitive rehabilitation of elderly adults.

Structured Floral Arrangement Program Benefits in Patients With Neurocognitive Disorder

We attempted to clarify positive benefits in cognitive abilities and motivation during our cognitive intervention [structured floral arrangement (SFA) program] for patients with neurocognitive disorder due to stroke, traumatic brain injury (TBI), and other related disorders. In this SFA program, participants are required to arrange cut flowers and leaves on absorbent foam according to an instruction sheet. In a previous study of patients with schizophrenia, our SFA program encouraged participants and contributed to stimulating their visuospatial process and memory. Here, 27 patients with neurocognitive disorders participated in this study. Sixteen patients were assigned to an SFA-treated group and participated in six sessions during two phases plus to daily activities. Eleven non-treated patients engaged only daily activities during the same period. We compared Apathy Scale scores and neuropsychological scores between the SFA-treated and non-treated patients. Their mean attendance rate was more than 90% during the two phases. SFA-treated patients copied a Rey–Osterrieth complex figure more accurately than non-treated patients (p < 0.05) during the later intervention phase, whereas during the earlier phase, accuracy was comparable between treated and non-treated groups. In the SFA-treated group, recall scores also improved (p < 0.01), and the positive outcomes were maintained for about 3 months (p < 0.05). The Apathy Scale scores did not show significant change in either the SFA-treated or non-treated groups. Our present results suggest that the SFA program encouraged continuous participation to cognitive intervention and was useful for ameliorating dysfunctions in visuospatial memory and recognition in patients with neurocognitive disorder.

The interference of negative emotional stimuli on context processing in mildly depressed undergraduates

Abstract Although previous studies reported a relationship between cognitive dysfunction and depressive symptoms, whether context processing relates to symptoms of depression remains unclear. Hence, the question of whether context processing in depressed individuals is negatively specific or a general deficit also remains unanswered. The purpose of our study was to investigate whether mildly depressed individuals would evince a context processing deficit in response to negative emotional stimuli interference. We employed Emotional AX-CPT (AX version Continuous Performance Task), in which negative distractors were presented in the interval between cue and probe stimuli. ANOVAs revealed that when negative distractors were presented, the depressed group made more BX errors than the non-depressed group, and that the depressed group made more BX errors in response to negative distractors than to neutral distractors. Our results suggest that mildly depressed individuals show a context processing deficit when negatively charged stimuli interfere with retaining contextual information.