Binge inhalation of
toluene, a psychoactive chemical found in many household and industrial products, leads acutely to intoxication with comorbid impairments in motor function and cognitive abilities that appear to recover quickly. Recent evidence, however, indicates that the administration of
toluene results in marked changes in neurons of the medial prefrontal cortex that persist for relatively longer periods compared with other brain regions. To elucidate the potential
toluene-induced (∼5000 ppm)
cognitive dysfunctions that continue following the recovery of locomotor abilities, rats were entered into a series of water maze tasks. Following acute
toluene intoxication, rats were initially severely impaired in their swimming ability and in their ability to learn and perform a visible platform task. After about 20 min, swimming behavior mostly returned to normal, although
cognitive impairments were still evident. Whereas rats with extensive
toluene-free training in the maze were able to show normal spatial recall following
toluene intoxication, the same acute
toluene exposure severely impaired reversal learning, with the rats showing a marked perseveration for the previously learned platform location. Our results indicate that
toluene inhalation results in specific
cognitive dysfunctions that outlast major impairments in motor abilities, which may be related to impairments in medial prefrontal cortex activity.