Semantic dementia and the left and right temporal lobes

• DOI: 10.1016/j.cortex.2017.08.024
• Publication Date: 2017-08-31T23:17:48Z
• Authors: Julie S. Snowden; Jennifer M. Harris; Jennifer C. Thompson; Christopher Kobyl...; Matthew Jones; Anna M. Richardson; David Neary
• Keywords: Semantic dementia; Amodal perception; Temporal cortex

Semantic dementia, a circumscribed disorder of semantic knowledge, provides unique model for understanding the neural basis representation. The study addressed areas contention: relative roles left and right temporal lobe, contribution anterior versus posterior cortex status lobes as amodal hub. Naming word comprehension was examined in 41 dementia patients, 31 with left-predominant 10 right-predominant atrophy. In keeping expectation, naming were significantly poorer patients. Structural magnetic resonance image analysis, using visual rating scale, showed strong inverse correlations between scores severity both lobe By contrast, performance more strongly correlated Analysis errors revealed correlation atrophy associative/functional descriptive responses, implying availability information. 'don't know' indicative loss linked to errors, hallmark hemisphere atrophy, especially lobe. Matched visual-verbal tasks (famous face name identification, Pyramids Palm trees pictures words, animal knowledge from 3-D models names) administered nine patients elicited variable correspondence on nonverbal verbal versions task. Marked dissociations demonstrated some patients: names/words faces/pictures/models cases. findings are compatible notion convergence, but less easily accommodated within framework conceptual data, which reconcile apparent contradictions literature, discussed light nature distribution degenerative change dementia.