Amygdala response to mother

In altricial species, like the human, the caregiver, very often the mother, is one of the most potent stimuli during development. The distinction between mothers and other adults is learned early in life and results in numerous behaviors in the child, most notably mother-approach and stranger wariness. The current study examined the influence of the maternal stimulus on amygdala activity and related circuitry in 25 developing children (n = 13) and adolescents (n = 12), and how this circuitry was associated with attachment-related behaviors. Results indicated that maternal stimuli were especially effective in recruiting activity in the left dorsal amygdala, and activity in this amygdala region showed increased functional connectivity with evaluative and motor regions during viewing of maternal stimuli. Increases in this left dorsal amygdala activity and related amygdala-cortical functional connectivity were associated with increased mother-approach behaviors as measured by in-scanner behavioral responding and out-of-scanner child-report. Moreover, age-related changes in amygdala activity to strangers statistically mediated the developmentally typical decline in stranger wariness seen across this period. These results suggest that mother-induced behaviors are enacted by maternal influence on amygdala-cortical circuitry during childhood and adolescence.     

Prolonged institutional rearing is associated with atypically large amygdala volume and difficulties in emotion regulation

Early adversity, for example poor caregiving, can have profound effects on emotional development. Orphanage rearing, even in the best circumstances, lies outside of the bounds of a species-typical caregiving environment. The long-term effects of this early adversity on the neurobiological development associated with socio-emotional behaviors are not well understood. Seventy-eight children, who include those who have experienced orphanage care and a comparison group, were assessed. Magnetic resonance imaging (MRI) was used to measure volumes of whole brain and limbic structures (e.g. amygdala, hippocampus). Emotion regulation was assessed with an emotional go-nogo paradigm, and anxiety and internalizing behaviors were assessed using the Screen for Child Anxiety Related Emotional Disorders, the Child Behavior Checklist, and a structured clinical interview. Late adoption was associated with larger corrected amygdala volumes, poorer emotion regulation, and increased anxiety. Although more than 50% of the children who experienced orphanage rearing met criteria for a psychiatric disorder, with a third having an anxiety disorder, the group differences observed in amygdala volume were not driven by the presence of an anxiety disorder. The findings are consistent with previous reports describing negative effects of prolonged orphanage care on emotional behavior and with animal models that show long-term changes in the amygdala and emotional behavior following early postnatal stress. These changes in limbic circuitry may underlie residual emotional and social problems experienced by children who have been internationally adopted.     

Not all risk taking behavior is bad: Associative sensitivity predicts learning during risk taking among high sensation seekers

Risk taking behavior can be both adaptive and maladaptive depending on context. The majority of studies on risk taking, however, focus on clinical populations and dangerous or harmful risk taking. Individual differences in learning during risk taking are rarely examined in relation to task performance. The present study examined risk taking and associated outcomes in an exploration-based instrumental learning task (Balloon Emotional Learning Task; BELT), which presented a series of balloons in which participants pump up for points. Consistent with prior work, sensation seeking predicted increased risk taking behavior. Importantly, however, a significant interaction between sensation seeking and associative sensitivity, an attentional construct defined as the frequency and remoteness of automatic cognitive activity, was found. Specifically, among individuals high in sensation seeking, associative sensitivity predicted fewer balloon explosions and an increase in points earned on the balloon condition with the most potential for feedback driven learning. Thus, these findings suggest that sensation seekers are a heterogeneous group, and secondary traits such as associative sensitivity moderate risk taking and learning according to context.     

Seeing yourself helps you see others

It has been proposed that self-face representations are involved in interpreting facial emotions of others. We experimentally primed participants' self-face representations. In Study 1, we assessed eye tracking patterns and performance on a facial emotion discrimination task, and in Study 2, we assessed emotion ratings between self and nonself groups. Results show that experimental priming of self-face representations increases visual exploration of faces, facilitates the speed of facial expression processing, and increases the emotional distance between expressions. These findings suggest that the ability to interpret facial expressions of others is intimately associated with the representations we have of our own faces.     

Female advantage for spatial location memory in both static and dynamic environments

A female advantage has previously been found for spatial location tests of object memory. Previous studies have used static, 2-D tasks to test this advantage. This study used a computerized adaptation of the game Concentration to test object location memory in both a static and dynamic array of 24 pairs of line drawings. The dynamic version of this task was used to better reflect the dynamic real world in which we usually use object location memory. Consistent with previous research, we observed a female advantage. This advantage was found to a similar extent in both the static and dynamic versions of the task. The female advantage for object location memory is a concrete advantage in spatial cognition that females show on the Concentration Task, regardless of the nature of the presentation environment.     

The face behind the mask: a developmental study

Faces are a rich and available source of social information, and the representation for faces is robust in adults (i.e. the face detection effect; Purcell & Stewart, 1988). The current study compared the developmental trajectory of the robustness of face perception against the trajectory for a non-face object. Participants (5-35 years old) were presented with rapid (17 and 33 millisecond) presentations of face and house stimuli and were instructed to identify the object category of the stimulus (face or house). There was an interaction between object type and age such that the developmental slope for face identification was steeper than the slope for house identification for the 17-millisecond presentation. These data show that faces are processed in a different way than a non-face object during the period from middle childhood through adolescence and adulthood, and this differential processing may involve the massive amount of exposure we have to faces.