Implicit olfactory abilities in traumatic brain injured patients.

To investigate implicit olfactory abilities in a group of anosmic traumatic brain injured (TBI) patients, an olfactomotor priming paradigm was administered. A group of matched normosmic/mildly microsmic TBI patients and a group of neurologically healthy participants served as controls. For all the groups, an interference effect was evident on the peak velocity of grip aperture when participants grasped a large target preceded by a "small" odor. The present results suggest that some form of implicit olfactory processing is preserved in TBI patients even when diagnosed as anosmic on the basis of explicit olfactory testing.