Ethanol and menstrual cycle interactions in the visual evoked response

Area of Science:

• Neuroscience
• Psychopharmacology
• Human Physiology

Background:

• Menstrual cycle phases influence hormonal levels, potentially affecting cognitive and neural functions.
• Ethanol (alcohol) is known to impact central nervous system activity, including visual processing.
• Cerebral hemisphere lateralization of cognitive functions is well-established.

Purpose of the Study:

• To investigate the influence of menstrual cycle phase on visual evoked responses (VERs) in normal women.
• To examine the effects of ethanol on VERs, considering dose-dependency and hemispheric differences.
• To explore potential interactions between menstrual cycle phase and ethanol's effects on brain activity.

Main Methods:

• Collected visual evoked responses (N120, P180 components) from central locations in both hemispheres.
• Tested 10 normal right-handed women in follicular and luteal phases of their menstrual cycle.
• Administered placebo and three doses of ethanol, measuring amplitude and latency, and calculating interhemispheric asymmetry.

Main Results:

• Follicular phase showed significant P180 latency asymmetry under baseline conditions; luteal phase had minimal P180 latency asymmetry.
• Ethanol dose-dependently reduced N120 and P180 amplitudes and prolonged N120 latency.
• Ethanol eliminated follicular P180 latency asymmetry and interacted with menstrual cycle phase for left hemisphere P180 amplitude and latency at low/moderate doses.

Conclusions:

• Menstrual cycle phase significantly modulates hemispheric asymmetry in visual evoked potentials.
• Ethanol exerts dose-dependent effects on visual evoked responses, impacting amplitude and latency.
• Interactions between ethanol and menstrual cycle phase suggest lateralized and biphasic effects of ethanol on brain function.