Interaction of choline and scopolamine in human memory

Area of Science:

• Neuroscience
• Pharmacology
• Cognitive Science

Background:

• Scopolamine is known to induce memory deficits.
• Previous research indicated partial reversal of scopolamine's effects by oral choline.
• The efficacy of divided choline doses and correlation with plasma levels required further investigation.

Purpose of the Study:

• To determine if 14 gm of choline, divided over 24 hours, could reverse scopolamine-induced memory impairment.
• To investigate the relationship between plasma choline concentration and cognitive effects.
• To compare findings with a previous single-dose choline study.

Main Methods:

• Ten healthy subjects participated in a placebo-controlled, within-subjects design.
• Memory tests were administered after receiving choline (14 gm divided) plus scopolamine, or placebo plus scopolamine, or placebo plus placebo.
• Plasma choline levels were measured and correlated with cognitive performance.

Main Results:

• Scopolamine significantly impaired memory performance in all conditions.
• No significant difference in memory performance was observed between choline and placebo conditions when co-administered with scopolamine.
• Plasma choline levels were elevated but did not correlate with memory performance.

Conclusions:

• Divided high-dose choline administration does not counteract scopolamine-induced amnesia in healthy individuals.
• Elevated plasma choline concentrations do not appear to enhance cognitive function in this context.
• The cognitive benefits of increased dietary choline are likely transient and of limited magnitude.