Structural Brain Network Correlated with Reading Impairment in Alzheimer's Disease.

AIM: Alzheimer's disease (AD) is the most common age-related neurodegenerative disease and leads to dementia. AD is characterized by progressive declines in memory and, as the disease progresses, language dysfunction. Although it has been reported that AD patients show progressive aphasia, no study has examined the relationship between language functions estimated by the Standard Language Test for Aphasia (SLTA) and brain network connectivity in Japanese AD patients. If present, such a relationship would be of particular interest because Japanese speakers are accustomed to mingling ideography and phonography. METHODS: 22 Japanese patients with AD who underwent 1.5-tesla MRI scan and SLTA, the scale for speech and reading impairment, participated in this study. We computed brain network connectivity metrics such as degree, betweenness centrality, and clustering coefficient, and estimated their relationships with the subscores of SLTA. RESULTS: There was a significant negative correlation between the score for "reading aloud Kanji words" and the clustering coefficient in the left inferior temporal region, bilateral hippocampal regions, and right parietotemporal region. We also found a significant negative correlation between the score for "auditory comprehension of words" and the clustering coefficient in the left prefrontal region. No significant relationship was found between the other SLTA scores and the network metrics. CONCLUSIONS: Our data suggest relationships between reading impairments and regional brain network connectivity in Japanese patients with AD. The brain connectome may provide adjunct biological information that could improve our understanding of reading impairment.

Feasibility study of Internet video-based speech-language activity for outpatients with primary progressive aphasia.

BACKGROUND: Primary progressive aphasia is a clinical dementia syndrome secondary to neurodegenerative disease characterized by language-related difficulties. Currently, there is no effective treatment for language impairment in primary progressive aphasia. In the present study, we investigated the feasibility of Internet video-based speech-language activities for this condition. METHODS: Twenty-three people with primary progressive aphasia (pwPPA) participated in the study and were provided with twelve speech-language activity videos on a dedicated website, with three sessions per week. The group that chose to continue with participation after three months of intervention received Internet activities for one year. Cognitive domains associated with persistence, treatment motivation, and video difficulty settings were statistically analyzed. RESULTS: After three months, 17 out of 23 participants opted to continue with the activities. The ability to follow oral commands which was measured pre intervention was higher in the group that continued compared with those participants who discontinued activity. The scores of two Standard Language Test of Aphasia subtests, sentence repetition and narrative writing-associated with the ability to comprehend and produce sentence structure-were highly correlated with motivation, interest and concentration in activity. Participants with different levels of primary progressive aphasia progression could participate in the same video-based activities when high-frequency words were used in the video. CONCLUSIONS: Internet video-based speech-language activity at home has potential as a useful tool for future primary progressive aphasia treatment because it provides a cost-effective approach to intensive intervention and overcomes barriers associated with traditional therapy approaches.

Squalor syndrome after focal orbitofrontal damage.

OBJECTIVE: To investigate a responsible lesion for squalor syndrome. BACKGROUND: Squalor syndrome is a behavioral disorder characterized by extreme self-neglect and domestic squalor. Although frontal lobe dysfunction has been postulated to account for squalor syndrome, the relevant part of the frontal lobe has not been elucidated. METHODS: A 49-year-old housewife who suffered rupture of an anterior communicating artery aneurysm at the age of 40 years was examined using a wide range of neuropsychologic tasks. Computed tomography of the head and brain single photon emission tomography with IMP was also carried out. RESULTS: Her performance on neuropsychologic testing was within the normal range, except for the gambling task. Computed tomography of the head showed low-density areas in the bilateral orbitofrontal cortices, basal forebrain, and right ventromedial caudate. Brain single photon emission tomography with IMP showed decreased regional cerebral blood flow in the bilateral orbitofrontal cortices and the basal forebrain. CONCLUSIONS: Our findings suggest that an orbitofrontal lesion may be responsible for squalor syndrome by leading to inappropriate decision-making and abnormal impulsivity.