Dichotic listening in patients with splenial and nonsplenial callosal lesions.
The authors found splenial lesions to be associated with left ear suppression in dichotic listening of consonant-vowel syllables. This was found in both a rapid presentation dichotic monitoring task and a standard dichotic listening task, ruling out attentional limitations in the processing of high stimulus loads as a confounding factor. Moreover, directed attention to the left ear did not improve left ear target detection in the patients, independent of callosal lesion location. The authors' data may indicate that auditory callosal fibers pass through the splenium more posterior than previously thought. However, further studies should investigate whether callosal fibers between primary and secondary auditory cortices, or between higher level multimodal cortices, are vital for the detection of left ear targets in dichotic listening.
Pollmann
Stefan
S
Day Clinic of Cognitive Neurology, University of Leipzig and Max-Planck-Institute of Cognitive Neuroscience, Germany. pollmann@cns.mpg.de
Maertens
Marianne
M
von Cramon
D Yves
DY
Lepsien
Joeran
J
Hugdahl
Kenneth
K
D000328:Adult; D000368:Aged; D001306:Auditory Pathways / Q000503:physiopathology; D002561:Cerebrovascular Disorders / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D003337:Corpus Callosum / Q000473:pathology* / Q000503:physiopathology; D004007:Dichotic Listening Tests; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006311:Hearing Disorders / Q000175:diagnosis* / Q000209:etiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010700:Phonetics; D012720:Severity of Illness Index