Olfactory functioning in temporal lobectomy patients.

Seventeen patients who received unilateral excision of the temporal lobe for intractable epilepsy were compared to 46 normal controls on a battery of tests of olfactory functioning. Tests included quality discrimination, immediate and delayed recognition memory, matching an odor to its visually or haptically presented source, and verbal identification of odors and the function of stimulus objects. In spite of clinically normal absolute sensitivity, the patients performed significantly worse than controls on all tests of olfactory functioning. There were no significant differences in performance between dominant and non-dominant lobectomy patients. Likely explanations for the uniformly impaired performance of patients include deficits in quality discrimination and minor lapses of attention.