Normal cognitive performance in patients with chronic alcoholism in contrast to patients with Korsakoff's syndrome

This study investigated which cognitive deficits are associated with chronic alcoholism. Neuropsychological profiles and MRI brain structure volumes of 14 patients with Korsakoff's syndrome, 15 patients with chronic alcoholism, and 16 healthy control subjects were compared. The patients with alcoholism had a normal cognitive performance and normal brain structure volumes. The patients with Korsakoff's syndrome had performance deficits on tests of memory, visuoperceptual, and executive functions, as well as reduced brain structure volumes. The results suggest that the cognitive deficits cannot be ascribed to mere chronic consumption of alcohol. If cognitive deficits are present in patients with chronic alcoholism, this may point to an underlying brain disorder.

Caffeine attenuates scopolamine-induced memory impairment in humans

Caffeine consumption can be beneficial for cognitive functioning. Although caffeine is widely recognized as a mild CNS stimulant drug, the most important consequence of its adenosine antagonism is cholinergic stimulation, which might lead to improvement of higher cognitive functions, particularly memory. In this study, the scopolamine model of amnesia was used to test the cholinergic effects of caffeine, administered as three cups of coffee. Subjects were 16 healthy volunteers who received 250 mg caffeine and 2 mg nicotine separately, in a placebo-controlled double-blind cross-over design. Compared to placebo, nicotine attenuated the scopolamine-induced impairment of storage in short-term memory and attenuated the scopolamine-induced slowing of speed of short-term memory scanning. Nicotine also attenuated the scopolamine-induced slowing of reaction time in a response competition task. Caffeine attenuated the scopolamine-induced impairment of free recall from short- and long-term memory, quality and speed of retrieval from long-term memory in a word learning task, and other cognitive and non-cognitive measures, such as perceptual sensitivity in visual search, reading speed, and rate of finger-tapping. On the basis of these results it was concluded that caffeine possesses cholinergic cognition enhancing properties. Caffeine could be used as a control drug in studies using the scopolamine paradigm and possibly also in other experimental studies of cognitive enhancers, as the effects of a newly developed cognition enhancing drug should at least be superior to the effects of three cups of coffee.