Verb generation in patients with focal frontal lesions: a neuropsychological test of neuroimaging findings.
What are the neural bases of semantic memory? Traditional beliefs that the temporal lobes subserve the retrieval of semantic knowledge, arising from lesion studies, have been recently called into question by functional neuroimaging studies finding correlations between semantic retrieval and activity in left prefrontal cortex. Has neuroimaging taught us something new about the neural bases of cognition that older methods could not reveal or has it merely identified brain activity that is correlated with but not causally related to the process of semantic retrieval? We examined the ability of patients with focal frontal lesions to perform a task commonly used in neuroimaging experiments, the generation of semantically appropriate action words for concrete nouns, and found evidence of the necessity of the left inferior frontal gyrus for certain components of the verb generation task. Notably, these components did not include semantic retrieval per se.
Thompson-Schill
S L
SL
Department of Psychology, 3815 Walnut Street, University of Pennsylvania, Philadelphia, PA 19104, USA. thompson@psych.upenn.edu
Swick
D
D
Farah
M J
MJ
D'Esposito
M
M
Kan
I P
IP
Knight
R T
RT
D000328:Adult; D000368:Aged; D001931:Brain Mapping; D001932:Brain Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000523:psychology; D002544:Cerebral Infarction / Q000000981:diagnostic imaging / Q000473:pathology / Q000523:psychology*; D005260:Female; D005625:Frontal Lobe / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology*; D007839:Functional Laterality; D006801:Humans; D007802:Language; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory; D008577:Meningeal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000523:psychology*; D008579:Meningioma / Q000000981:diagnostic imaging / Q000473:pathology* / Q000523:psychology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D012044:Regression Analysis; D014057:Tomography, X-Ray Computed; D014705:Verbal Behavior; D014825:Vocabulary