Effects of a single transdermal nicotine dose on cognitive performance in adults with Down syndrome

Subjects with Down syndrome exhibit various types of cognitive impairment. Neuropathological and neurochemical studies revealed similarities between D own syndrome and Alzheimer's disease, cholinergic deficits being the most c onsistent findings. To explore the potential for cognitive enhancement util izing nicotinic stimulation, 8 patients with Down syndrome (aged 18.5-31 ye ars) received placebo and a single dose of transdermal nicotine (5 mg patch ) over 2 h in a single-blind, within-subjects repeated measures design. Aud itory event-related potentials (ERPs) and neuropsychological tests, compris ing digit symbol performance subtest from WAIS-R and the Frankfurt Attentio n Inventory (FAIR) were performed. Effects of nicotine administration in Do wn syndrome individuals were a decrease of ERP-P3 latency in 7 of 8 subject s (electrode position Cz: 386.9 +/- 24.0ms vs. 363.1 +/- 26.9.2ms, placebo vs. nicotine, respectively; P = 0.058) and an increase of ERP-P3 amplitude in 6 of 8 subjects (electrode position Cz: 17.4 +/- 5.5 vs. 18.0 +/- 4.5 mu V, placebo vs. nicotine respectively; P = 0.725). Neuropsychological tests exhibited improvements in digit symbol performance subtest in 4 of 8 subjec ts and 7 of 8 subjects in the Frankfurt Attention Inventory. These results suggest that stimulating central nicotinic receptors might have an acute co gnitive benefit in young adult Down syndrome subjects.