Editorial significance: Knott separate and combined effects of scopolamine and mecamylamine on ERP

✍ Scribed by Mark S. George

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 35 KB
• Volume: 14
• Category: Article
• ISSN: 0885-6222
• DOI: 10.1002/(sici)1099-1077(199907)14:5<305::aid-hup132>3.0.co;2-2

✦ Synopsis

Knott Separate and Combined Eects of Scopolamine and Mecamylamine on ERP

Understanding the pharmacology of learning and attention is of huge importance in both health and in disease states like dementia. One of the main areas of research has been looking at the cholinergic system. Numerous therapeutic agents for Alzheimer's disease have activity in this realm. In this context, using challenge studies in healthy subjects, probing the cholinergic system while also assessing cognitive function are important.

In this article, Knott and colleagues used eventrelated potentials in 10 healthy adults who were performing a continuous performance task, and studied the eects of a nicotinic blocker, a muscarinic blocker, or a combination of both. Both compounds alone and in combination resulted in decreased alertness and slower reaction times. Neither compound aected response accuracy. Evoked potentials were reduced only with the nicotinic blockade.

Reduced evoked potentials have been described in Alzheimer's disease. These results suggest that nicotinic receptors play a more vital role than muscarinic receptors in visual information processing. Further work comparing and contrast-ing these two systems is important in understanding their dierential eects in health and disease.

TAKE HOME POINTS 1. Scopolamine and mecamylamine administered separately and in combination, slowed visual and auditory reaction times to equivalent degrees. 2. Mecamylamine, but not scopolamine, reduced self-reports of mental alertness. 3. Mecamylamine, but not scopolamine, reduced visual P300 amplitudes.