Summary: Researchers reveal dopamine, a neurotransmitter commonly associated with reward plays a key role in social cognition and emotional recognition.
The neurotransmitter dopamine, famous for its role in reward, is also involved in recognizing emotions, according to new research published in Journal of Neuroscience.
People with disrupted dopamine levels, like in Parkinson’s disease and schizophrenia, often struggle with aspects of social cognition.
Yet the link between dopamine and specific social behaviors remained elusive, in part due to mixed results from studies that did not account for individual differences in dopamine levels.
In a study by Schuster et al., healthy participants took haloperidol — a dopamine receptor inhibitor — on one day and a placebo pill on another before completing an emotion recognition task.
They assessed videos of people expressing an emotion through their posture and gait (i.e., slow movements for sadness, quick, jerky movements for anger). The researchers also indirectly measured each person’s baseline dopamine levels by testing their working memory.
The effects of haloperidol varied in each person depending on their baseline dopamine levels. In people with low dopamine, the drug increased their ability to recognize emotions, while in people with high dopamine, the drug impaired their ability.
Future work will examine how changes in dopamine levels in disorders like Parkinson’s disease contribute to social cognition impairments.
About this dopamine and emotion research news
Original Research: Closed access.
“Dopaminergic modulation of dynamic emotion perception” by B.A. Schuster, S. Sowden, A.J. Rybicki, D.S. Fraser, C. Press, P. Holland and J.L. Cook. Journal of Neuroscience
Dopaminergic modulation of dynamic emotion perception
Emotion recognition abilities are fundamental to our everyday social interaction. A large number of clinical populations show impairments in this domain, with emotion recognition atypicalities being particularly prevalent among disorders exhibiting a dopamine system disruption (e.g., Parkinson’s disease).
Although this suggests a role for dopamine in emotion recognition, studies employing dopamine manipulation in healthy volunteers have exhibited mixed neural findings and no behavioural modulation.
Interestingly, whilst a dependence of dopaminergic drug effects on individual baseline dopamine function has been well established in other cognitive domains, the emotion recognition literature so far has failed to account for these possible interindividual differences.
The present within-subjects study therefore tested the effects of the dopamine D2 antagonist haloperidol on emotion recognition from dynamic, whole-body stimuli while accounting for interindividual differences in baseline dopamine. 33 healthy male and female adults rated emotional point-light walkers (PLWs) once after ingestion of 2.5 mg haloperidol and once after placebo.
To evaluate potential mechanistic pathways of the dopaminergic modulation of emotion recognition, participants also performed motoric and counting-based indices of temporal processing.
Confirming our hypotheses, effects of haloperidol on emotion recognition depended on baseline dopamine function, where individuals with low baseline dopamine showed enhanced, and those with high baseline dopamine decreased emotion recognition.
Drug effects on emotion recognition were related to drug effects on movement-based and explicit timing mechanisms, indicating possible mediating effects of temporal processing.
Results highlight the need for future studies to account for baseline dopamine and suggest putative mechanisms underlying the dopaminergic modulation of emotion recognition.
A high prevalence of emotion recognition difficulties amongst clinical conditions where the dopamine system is affected suggests an involvement of dopamine in emotion recognition processes.
However, previous psychopharmacological studies seeking to confirm this role in healthy volunteers thus far have failed to establish whether dopamine affects emotion recognition and lack mechanistic insights.
The present study uncovered effects of dopamine on emotion recognition in healthy individuals by controlling for interindividual differences in baseline dopamine function and investigated potential mechanistic pathways via which dopamine may modulate emotion recognition.
Our findings suggest that dopamine may influence emotion recognition via its effects on temporal processing, providing new directions for future research on typical and atypical emotion recognition.