Time-Resolved Influences of Functional DAT1 and COMT Variants on Visual Perception and Post-Processing

Stephan Bender,Christine Jennen-Steinmetz,Franz Resch,Tobias Banaschewski,Christine Freitag,Manfred Laucht,Daniel Brandeis,Thomas Rellum,Jens Treutlein,Marcella Rietschel

doi:10.1371/journal.pone.0041552

Abstract

BackgroundDopamine plays an important role in orienting and the regulation of selective attention to relevant stimulus characteristics. Thus, we examined the influences of functional variants related to dopamine inactivation in the dopamine transporter (DAT1) and catechol-O-methyltransferase genes (COMT) on the time-course of visual processing in a contingent negative variation (CNV) task.Methods64-channel EEG recordings were obtained from 195 healthy adolescents of a community-based sample during a continuous performance task (A-X version). Early and late CNV as well as preceding visual evoked potential components were assessed.ResultsSignificant additive main effects of DAT1 and COMT on the occipito-temporal early CNV were observed. In addition, there was a trend towards an interaction between the two polymorphisms. Source analysis showed early CNV generators in the ventral visual stream and in frontal regions. There was a strong negative correlation between occipito-temporal visual post-processing and the frontal early CNV component. The early CNV time interval 500–1000 ms after the visual cue was specifically affected while the preceding visual perception stages were not influenced.ConclusionsLate visual potentials allow the genomic imaging of dopamine inactivation effects on visual post-processing. The same specific time-interval has been found to be affected by DAT1 and COMT during motor post-processing but not motor preparation. We propose the hypothesis that similar dopaminergic mechanisms modulate working memory encoding in both the visual and motor and perhaps other systems.

Highlights

Event-related potentials offer the possibility to examine the influence of genes on cognitive processes with a high time resolution
Previous studies have established that contingent negative variation (CNV) is composed of components which depend upon the cue S1 or which depend on the target stimulus S2 [7]
Because we found that N700 occurs across different modalities with a comparable time-course [11], here we investigated the effects of three functional polymorphisms in the catechol-O-methyltransferase genes (COMT) and DAT1 genes on time resolved visual processing

Summary

Introduction

Event-related potentials offer the possibility to examine the influence of genes on cognitive processes with a high time resolution. While frontal potentials have been associated with orienting and recruitment of resources for task performance [9,10], modality-specific encoding in visual areas during the same time interval has been proposed to represent an important short-term memory buffer [5,6] This late negativity over occipito-temporal areas occurs about half a second after single visual, but not auditory or somatosensory stimuli [11,12]. Post-processing which exceeds the stimulus duration or initial stimulus perception (respectively movement execution) occurs over modality-dependent areas following short visual stimuli [6,13], movements [14,15], somatosensory stimuli [16], and auditory stimuli [5,11] In contrast to these modality-dependent activations during early CNV, a frontal negativity which adds to the modality dependent activation has been found for all sensory modalities [11,12] and may reflect a supramodal response. We examined the influences of functional variants related to dopamine inactivation in the dopamine transporter (DAT1) and catechol-O-methyltransferase genes (COMT) on the time-course of visual processing in a contingent negative variation (CNV) task

Results

Discussion

Conclusion