Sleep deprivation and interference by emotional distracters.
OBJECTIVE
We determined if sleep deprivation would amplify the effect of negative emotional distracters on working memory.


METHODS
A crossover design involving 2 functional neuroimaging scans conducted at least one week apart. One scan followed a normal night of sleep and the other followed 24 h of sleep deprivation. Scanning order was counterbalanced across subjects.


METHODS
The study took place in a research laboratory.


METHODS
24 young, healthy volunteers with no history of any sleep, psychiatric, or neurologic disorders.


METHODS
N/A.


RESULTS
Study participants were scanned while performing a delayed-response working memory task. Two distracters were presented during the maintenance phase, and these differed in content: highly arousing, negative emotional scenes; low-arousing, neutral scenes; and digitally scrambled versions of the pictures. Irrespective of whether volunteers were sleep deprived, negative emotional (relative to neutral) distracters elicited greater maintenance-related activity in the amygdala, ventrolateral prefrontal cortex, and fusiform gyri, while concurrently depressing activity in cognitive control regions. Individuals who maintained or increased distracter-related amygdala activation after sleep deprivation showed increased working memory disruptions by negative emotional distracters. These individuals also showed reduced functional connectivity between the amygdala and the ventromedial and dorsolateral prefrontal cortices, regions postulated to mediate cognitive control against emotional distraction.


CONCLUSIONS
Increased distraction by emotional stimuli following sleep deprivation is accompanied by increases in amygdala activation and reduced functional connectivity between the amygdala and prefrontal cognitive control regions. These findings shed light on the neural basis for interindividual variation in how negative emotional stimuli might distract sleep deprived persons.
Cognitive Neuroscience Laboratory, Duke-NUS Graduate Medical School Singapore, Singapore. chauhym@singnet.com.sg
Lisa Y M
LY
Chuah
Florin
F
Dolcos
Annette K
AK
Chen
Hui
H
Zheng
Sarayu
S
Parimal
Michael W L
MW
Chee
D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping / Q000379:methods; D003071:Cognition; D018592:Cross-Over Studies; D004644:Emotions; D005145:Face; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008570:Memory, Short-Term; D010775:Photic Stimulation / Q000379:methods; D012892:Sleep Deprivation / Q000523:psychology*; D013647:Task Performance and Analysis; D055815:Young Adult