Studies

Becoming a parent represents an important developmental period within adulthood. We are interested in understanding the neural correlates of parenting using EEG/ERP and we collaborate with colleagues in the Department of Psychiatry for complimentary assessments using fMRI. We are examining parenting across the postpartum period, and many of our mothers attend visits at 3 months and then 6 months postpartum. We also take saliva samples during the visits so we can assess changes in oxytocin levels and whether this predicts neural responses in our paradigms. Outside of Yale, our collaborators in these studies are Drs. Josephine Johns (University of North Carolina at Chapel Hill) and Lane Strathearn (Baylor College of Medicine).

Currently we are focusing on two key areas in our parenting program of research:

• Maternal sensitivity to infant cues. In these studies, we explore neural sensitivity to infant cues of affect. Our stimuli include both infant cries (varying in distress levels) and photographs of infant faces (varying in expression). In addition to exploring individual differences within mothers and how this affects sensitivity to infant cues, we are also assessing whether maternal substance use influences perception of infant affect.
• Maternal emotion regulation. Here we are assessing the neural correlates of emotion regulation in mothers and non-mothers when viewing photographs of infants in different emotional states. We are interested in whether the neurobiological and experiential changes in becoming a parent facilitate more effective emotion regulation strategies.

In the first two phases of this study, we described a continuum of developmental impairment and dysfunction among prenatally cocaine-exposed children that includes emotional lability, impaired visuospatial processing and visual motor integration, delayed cognitive expressive and receptive language development, impulsivity and difficulty inhibiting prepotent responses, attenuated stress response systems, and increased parental dysfunction. In the second phase we are following up our findings and assessing children exposed prenatally to cocaine and two non-cocaine-exposed comparison groups twice yearly with convergent measures of the following child-related outcomes:

• Cognitive, language functioning, and school (academic) achievement.
• Neurophysiological Functioning: Aspects of executive functioning reflecting prefrontal cortical systems and attention regulation.
• Arousal regulation operationalized as the startle response.
• Social adaptation, maladaptation, and psychopathology: Adaptive and maladaptive behaviors, social adjustment, and incidence of childhood psychopathology.
• Physical health and development.

Portable dense array EEG system

Considerable evidence has accumulated to suggest that startle, a reflex response to stimuli with abrupt onset, is a sensitive index of vulnerability to increased anxiety or states of arousal and that individual variation in the startle response under varying conditions provides a window on the development of centrally based mechanisms for arousal and state regulation. The purpose of these studies is to explore the role of the emotion or anxiety (fear) potentiated startle response (measured using the eye blink reflex) in a variety of different clinical and normal populations to test the hypothesis that the degree of potentiation will depend upon the clinical disorder and its underlying pathophysiology.

Neural Correlates of Perceptual Expertise in Autism

This project contrasts brain specialization for social information (faces) versus non-social information (letters of the alphabet) in individuals with autism. Using 256 channel nets, the study will also compare neural origins for these “expert stimuli” in children with autism spectrum disorder and typically developing children.

Face ERPs and Outcome in Autism

Children initially evaluated at age two are being re-evaluated at age eight to examine predictors of outcome and developmental trajectories. Along with neuropsychological, speech/language, and social assessments, electrophysiological brain response to human faces will be examined as an outcome measure.

Social Context and Face Perception in Autism

This study examines how typically developing people and people with autism interpret ambiguous social information. Neural responses are recorded to varying forms of degraded and partial person-related information, simultaneously examining learning as ambiguity is reduced.

Personality Characteristics and Electrophysiological Face Responses

Groups of adults scoring high or low on a measure of extroversion are compared in their brain responses to veridical human faces and computer-generated cartoon faces.

Modulation of Electrophysiological Face Response by Point of Gaze

By manipulating an individual’s point of gaze on an image of a human face, this project examines the influence of visual attention on face-related brain activity.

Tourette Syndrome (TS) is a chronic and impairing neurological disorder characterized by motor and phonic tics. Until recently, the only option for treating the tics of TS was medication. Although medication remains the mainstay of treatment, there is growing evidence that behavioral therapy, known as Habit Reversal Training (HRT), can be effective even for presumed involuntary tics. If HRT is effective, we are interested in learning about how it works.

To this end, we are conducting a study using electroencephalography (EEG) in order to examine how HRT produces tic reduction effects. The idea for our pilot study is based on research by British neuroscientist Deborah Serrien, who demonstrated that successful tic suppression by adults with TS was associated with higher levels of EEG coherence over the cortical areas involved in movement control. Serrien concluded that this finding reflects an adaptive mechanism of superior motor control in individuals with TS. We reasoned that if HRT is successful for tic reduction, it can also enhance the brain mechanism of motor control.

To test this hypothesis, we have been collecting EEG data before and after HRT in children with TS. So far we have analyzed the data from five 8 to 12 year old children who participated in the study and the results are encouraging. All five children demonstrated clinically meaningful symptom reduction after treatment based on the tic ratings conducted by the independent clinician. Consistent with the hypothesis of this study, the reduction of tics was paralleled by the increase in EEG alpha coherence. Even though our sample is small, we are very enthusiastic about these results.

To pursue further examination of brain mechanisms of response to behavior therapy for tics, Denis Sukhodolsky has recently received a 5 year career development award from the National Institutes of Mental Health. Because HRT is a promising but not yet proven treatment for tics, we are now conducting a randomized study of HRT and its effects on tics and EEG coherence.