Left hand tactile agnosia after posterior callosal lesion.
We report a patient with a hemorrhagic lesion encroaching upon the posterior third of the corpus callosum but sparing the splenium. She showed marked difficulties in recognizing objects and shapes perceived through her left hand, while she could appreciate elementary sensorial features of items tactually presented to the same hand flawlessly. This picture, corresponding to classical descriptions of unilateral associative tactile agnosia, was associated with finger agnosia of the left hand. This very unusual case report can be interpreted as an instance of disconnection syndrome, and allows a discussion of mechanisms involved in tactile object recognition.
Balsamo
Maddalena
M
Neuropsychology Laboratory, Department of Psychology, Second University of Naples, Naples, Italy.
Trojano
Luigi
L
Giamundo
Arcangelo
A
Grossi
Dario
D
D000328:Adult; D000377:Agnosia / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D003337:Corpus Callosum / Q000473:pathology*; D004192:Discrimination, Psychological; D005260:Female; D007839:Functional Laterality; D006225:Hand / Q000294:innervation; D006801:Humans; D009434:Neural Pathways / Q000473:pathology*; D011597:Psychomotor Performance; D013236:Stereognosis