Neural activation underlying emotional interference of cognitive control in rotating shift workers: moderating effects of the prefrontal cortex response on the association between sleep disturbance and depressive symptoms

Sun-Young Kim ¹, Kyung Hwa Lee ^2,3, Hayoung Lee ³

⁰Department of Psychiatry, Ewha Womans University College of Medicine, Ewha Womans University Seoul Hospital, Seoul, Republic of Korea.

Sleep +

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September 15, 2022

View abstract on PubMed

Summary

Rotating shift work disrupts emotional processing, increasing left dorsolateral prefrontal cortex (DLPFC) activation. This heightened DLPFC activity links sleep disturbance to depressive symptoms in shift workers.

Area Of Science

Neuroscience
Occupational Health
Psychiatry

Background

Rotating shift work is associated with sleep disturbances and increased risk of mood disorders.
Emotional interference processing is a key cognitive function potentially affected by shift work.
Understanding the neural mechanisms linking sleep disturbance and mood in shift workers is crucial for targeted interventions.

Purpose Of The Study

To investigate altered neural function in emotional interference among rotating shift workers.
To examine the role of neural function in linking sleep disturbance with depressive and anxiety symptoms.
To identify specific brain regions involved in the relationship between shift work, sleep, and mood.

Main Methods

Functional magnetic resonance imaging (fMRI) was used to assess brain activation during an emotional Stroop task in 60 rotating shift workers and 61 controls.
Participants completed self-report measures for sleep disturbance and mood symptoms, alongside sleep diaries and actigraphy.
Moderating models were analyzed to explore the relationship between brain activation, sleep disturbance, and mood symptoms.

Main Results

Rotating shift workers exhibited greater activation in the left dorsolateral prefrontal cortex (DLPFC) compared to controls when processing negative emotional words.
Reaction times were longer for negative emotional and sleep-related words compared to neutral words across all participants.
Higher activation in the left DLPFC during negative emotional word processing was associated with a stronger link between sleep disturbance and depressive symptoms.

Conclusions

The left DLPFC plays a significant role in heightened sensitivity to emotional information in rotating shift workers, potentially due to circadian misalignment.
Left DLPFC activation moderates the association between sleep disturbance and depressive symptoms in this population.
Identifying the role of the left DLPFC offers potential targets for interventions aimed at improving sleep and mood in rotating shift workers.

Keywords:

circadian misalignment emotional Stroop task fMRI left DLPFC rotating shift work