Event-related potentials reflect impaired temporal interval learning following haloperidol administration

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Psychopharmacology

Background:

• Dopamine system signals to anterior cingulate cortex are crucial for reward learning and performance monitoring.
• Homologous medial frontal negativities, the feedback-related negativity (FRN) and error-related negativity (ERN), reflect dopamine-dependent prediction errors.
• Haloperidol, a dopamine receptor antagonist, is known to attenuate the ERN, but its effect on the FRN remains unevaluated.

Purpose of the Study:

• To investigate the effects of haloperidol on both the ERN and FRN.
• To determine if haloperidol dissociates the neurobiological underpinnings of ERN and FRN.
• To explore the relationship between these event-related potentials and behavioral indices of learning and performance.

Main Methods:

• Healthy participants received haloperidol, diphenhydramine (active control), or placebo in a double-blind, randomized manner.
• Event-related potentials (ERN, FRN, Pe, P300) were recorded during a temporal interval learning task (TILT).
• Correlations between electrophysiological measures and behavioral outcomes (learning, accuracy, post-error adjustments) were analyzed.

Main Results:

• Haloperidol significantly reduced the ERN, particularly following fast timing errors, and this reduction correlated with less adaptive post-error performance.
• The FRN was not affected by drug condition, but larger FRN amplitude was associated with improved overall accuracy.
• No significant drug effects were observed on centroparietal positivities (Pe, P300).

Conclusions:

• The findings support a functional and neurobiological dissociation between the ERN and FRN.
• The ERN appears more directly involved in automatic error-related performance adjustments.
• The FRN is associated with learning and overall accuracy, independent of acute haloperidol administration in this context.