Increased sensitivity to positive social stimuli in monozygotic twins at risk of bipolar vs. unipolar disorder
Research output: Contribution to journal › Journal article › Research › peer-review
BACKGROUND: Abnormalities in affective cognition are putative endophenotypes for bipolar and unipolar disorders but it is unclear whether some abnormalities are disorder-specific. We therefore investigated affective cognition in monozygotic twins at familial risk of bipolar disorder relative to those at risk of unipolar disorder and to low-risk twins.
METHODS: Seventy monozygotic twins with a co-twin history of bipolar disorder (n = 11), of unipolar disorder (n = 38) or without co-twin history of affective disorder (n = 21) were included. Variables of interest were recognition of and vigilance to emotional faces, emotional reactivity and -regulation in social scenarios and non-affective cognition.
RESULTS: Twins at familial risk of bipolar disorder showed increased recognition of low to moderate intensity of happy facial expressions relative to both unipolar disorder high-risk twins and low-risk twins. Bipolar disorder high-risk twins also displayed supraliminal attentional avoidance of happy faces compared with unipolar disorder high-risk twins and greater emotional reactivity in positive and neutral social scenarios and less reactivity in negative social scenarios than low-risk twins. In contrast with our hypothesis, there was no negative bias in unipolar disorder high-risk twins. There were no differences between the groups in demographic characteristics or non-affective cognition.
LIMITATIONS: The modest sample size limited the statistical power of the study.
CONCLUSIONS: Increased sensitivity and reactivity to positive social stimuli may be a neurocognitive endophenotype that is specific for bipolar disorder. If replicated in larger samples, this 'positive endophenotype' could potentially aid future diagnostic differentiation between unipolar and bipolar disorder.
|Journal||Journal of Affective Disorders|
|Number of pages||7|
|Publication status||Published - May 2018|
- Adult, Affective Symptoms/genetics, Attention, Bipolar Disorder/genetics, Cognition, Depressive Disorder/genetics, Diseases in Twins/genetics, Emotions/physiology, Endophenotypes, Facial Expression, Female, Humans, Male, Risk, Twins, Monozygotic/genetics