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Biology subjects

Nance, M. G.

Publications and source records attributed to Nance, M. G..

3 recordsLinked to original sources

Parent attention-orienting behavior is associated with neural entropy in infancy

Parents play a significant role in directing infants attention to environmental stimuli via joint attention. We hypothesized that infants whose parents provide more bids for joint attention will display a more complex neural response when viewing social scenes. Sixty-one 8-month-old infants underwent electroencephalography (EEG) while viewing videos of joint-and parallel-play and participated in a parent-infant free play interaction. EEG data was analyzed using multiscale entropy, which quantifies moment-to-moment neural variability. Free play interactions were coded for parent alternating gaze, a behavioral mechanism for directing attention to environmental cues. We found a significant positive association between parent alternating gaze and neural entropy in frontal and central brain regions. These results suggest a relationship between parent behavior and infant neural mechanisms that regulate social attention, underlying the importance of parent cues in the formation of neural networks in infancy.

neuroscience↗

Infant neural sensitivity to affective touch is associated with maternal postpartum depression

Classic attachment theory emphasizes the sensitivity of the parent to perceive and appropriately respond to the infants cues. However, parent-child attachment is a dyadic interaction that is also dependent upon the sensitivity of the child to the early caregiving environment. Individual differences in infant sensitivity to parental cues is likely shaped by both the early caregiving environment as well as the infants neurobiology, such as perceptual sensitivity to social stimuli. Here, we investigated associations between maternal postpartum depression and infant neurological sensitivity to affective touch using brain signal entropy - a metric of the brains moment-to-moment variability related to signal processing. We recruited two independent samples of infants aged 0-5 months. In Sample 1 (n=79), we found increased levels of maternal postpartum depression were associated with diminished perceptual sensitivity - i.e. lower entropy - to affective tactile stimulation specifically within the primary somatosensory cortex. In Sample 2 (n=36), we replicated this finding and showed that this effect was not related to characteristics of the touch administered during the experiment. These results suggest that decreased affective touch early in life - a common consequence of postpartum depression - likely impacts the infants perceptual sensitivity to affective touch and ultimately the formation of experience-dependent neural networks that support the successful formation of attachment relationships.

neuroscience↗

Epigenetic and neural correlates of selective social attention across adulthood

Social isolation is one of the strongest predictors of increased risk of mortality in older adulthood. The ability to form and maintain the social relationships that mitigate this risk is partially regulated by the oxytocinergic system and ones ability to attend to and process social information. We have previously shown that an epigenetic change to the DNA of the oxytocin receptor gene (OXTR methylation) affects the salience of social information in young adults. Little is known about how the oxytocinergic system ages and what effect this aging system has on social cognitive abilities throughout the lifespan. Here we explore age-related differences in the association between neural response during selective social attention and OXTR DNA methylation in young and older adults. We find that older adults activate diffuse areas of visual cortex and dorsolateral prefrontal cortex during selective social attention, consistent with the dedifferentiation and compensatory neural activation commonly reported in aging. We find a significant age-by-OXTR methylation interaction on neural response when attending to social stimuli in a complex display; young adults display a positive association between OXTR methylation and neural activation, replicating our prior finding that young adults with presumed diminished endogenous access to oxytocin recruit regions of the attentional cortex to a greater extent. This association does not hold for older adults. Instead, perceived social support interacts with OXTR methylation to influence neural response during selective social attention. These data suggest that environmental factors like social support moderate biological processes in aging and highlight the importance of a lifespan perspective for understanding associations between individual differences in the oxytocinergic system, neural function, and social behavior.

neuroscience↗