Brad E. Sheese

Developing Mechanisms of Self-Regulation in Early Life.

Children show increasing control of emotions and behavior during their early years. Our studies suggest a shift in control from the brain’s orienting network in infancy to the executive network by the age of 3—4 years. Our longitudinal study indicates that orienting influences both positive and negative affect, as measured by parent report in infancy. At 3—4 years of age, the dominant control of affect rests in a frontal brain network that involves the anterior cingulate gyrus. Connectivity of brain structures also changes from infancy to toddlerhood. Early connectivity of parietal and frontal areas is important in orienting; later connectivity involves midfrontal and anterior cingulate areas related to executive attention and self-regulation.

Control Networks and Neuromodulators of Early Development.

In adults, most cognitive and emotional self-regulation is carried out by a network of brain regions, including the anterior cingulate, insula, and areas of the basal ganglia, related to executive attention. We propose that during infancy, control systems depend primarily upon a brain network involved in orienting to sensory events that includes areas of the parietal lobe and frontal eye fields. Studies of human adults and alert monkeys have shown that the brain network involved in orienting to sensory events is moderated primarily by the nicotinic cholinergic system arising in the nucleus basalis. The executive attention network is primarily moderated by dopaminergic input from the ventral tegmental area. A change from cholinergic to dopaminergic modulation would be a consequence of this switch of control networks and may be important in understanding early development. We trace the attentional, emotional, and behavioral changes in early development related to this developmental change in regulative networks and their modulators.

Executive attention and self-regulation in infancy

This study investigates early executive attention in infancy by studying the relations between infant sequential looking and other behaviors predictive of later self-regulation. One early marker of executive attention development is anticipatory looking, the act of looking to the location of a target prior to its appearance in that location, a process that involves endogenous control of visual orienting. Previous studies have shown that anticipatory looking is positively related to executive attention as assessed by the ability to resolve spatial conflict in 3-4-year-old children. In the current study, anticipatory looking was positively related to cautious behavioral approach in response to non-threatening novel objects in 6- and 7-month-old infants. This finding and previous findings showing the presence of error detection in infancy are consistent with the hypothesis that there is some degree of executive attention in the first year of life. Anticipatory looking was also related to the frequency of distress, to looking away from disturbing stimuli, and to some self-regulatory behaviors. These results may indicate either early attentional regulation of emotion or close relations between early developing fear and later self-regulation. Overall, the results suggest the presence of rudimentary systems of executive attention in infants and support further studies using anticipatory looking as a measure of individual differences in attention in infancy.

Developing Attention: Behavioral and Brain Mechanisms

Brain networks underlying attention are present even during infancy and are critical for the developing ability of children to control their emotions and thoughts. For adults, individual differences in the efficiency of attentional networks have been related to neuromodulators and to genetic variations. We have examined the development of attentional networks and child temperament in a longitudinal study from infancy (7 months) to middle childhood (7 years). Early temperamental differences among infants, including smiling and laughter and vocal reactivity, are related to self-regulation abilities at 7 years. However, genetic variations related to adult executive attention, while present in childhood, are poor predictors of later control, in part because individual genetic variationmay have many small effects and in part because their influence occurs in interaction with caregiver behavior and other environmental influences. While brain areas involved in attention are present during infancy, their connectivity changes and leads to improvement in control of behavior. It is also possible to influence control mechanisms through training later in life. The relation between maturation and learning may allow advances in our understanding of human brain development.

Variations in catechol-O-methyltransferase gene interact with parenting to influence attention in early development

Attention influences many aspects of cognitive development. Variations in the catechol-O-methyltransferase (COMT) gene, known to affect dopamine neurotransmission, have frequently been found to influence attention in adults and older children. In this paper we examined 2 year old children and found that variation in the COMT gene influenced attention in a task involving looking to a sequence of visual stimuli. Because the influence of another dopamine-related gene (DRD4) has been shown to interact with parenting quality at this age, we explored parenting in relation to variations in the COMT gene. Variations in COMT interacted with parenting quality to influence our attention measure. The Val(108/158)Met polymorphism of COMT is commonly used to determine allelic groups, but recently haplotypes of several polymorphisms within this gene have been shown to be more strongly associated with perceived pain. Since attention and pain both involve the activation of the anterior cingulate gyrus in imaging studies, we compared the Val(108/158)Met influence with the COMT haplotypes and found the latter to be more predictive of attention. Our results confirm that important aspects of cognitive development including attention depend on the interaction of genes and early environment.

Genetic variation influences on the early development of reactive emotions and their regulation by attention

Introduction. Individual differences in temperament and attention provide an important link between normal and pathological development. Previous studies suggest that during infancy, orienting of attention is associated with higher levels of positive affect and lower levels of negative affect. For older children and adults, self-regulation, as measured by ratings of effortful control, is consistently associated with lower levels of negative affect such as sadness and distress. Methods. In the current paper we use a longitudinal study of children at ages 6–7 months (Time 1) and 18–20 months (Time 2) to examine how variations in candidate genes relate to emotional and self-regulatory aspects of temperament. Results. In accord with previous findings, parent ratings of orienting were positively related to positive affect only during infancy. Genetic variation in COMT was related to positive affect at Time l but not Time 2. Negative affect at both Time 1 and Time 2 was related to genetic variation in SNAP25. Genetic variation in CHRNA4 was related to Effortful Control at Time 2. Conclusions. These findings lend support to the early modulation of emotion by aspects of orienting (Time 1) and executive attention (Time 2), and indicate that emotional reactivity and its regulation are modulated by different genes.

Methylation polymorphism influences practice effects in children during attention tasks

ABSTRACT Epigenetic mechanisms mediate the influence of experience on gene expression. Methylation is a principal method for inducing epigenetic effects on DNA. In this paper, we examine alleles of the methylenetetrahydrofolate reductase (MTHFR) gene that vary enzyme activity, altering the availability of the methyl donor and thus changing the efficiency of methylation. We hypothesized that alleles of the MTHFR gene would influence behavior in an attention-related task in conjunction with genes known to influence attention. We found that seven-year-old children homozygous for the C allele of MTHFR in interaction with the catechol O-methyltransferase (COMT) gene showed greater improvement in overall reaction time (RT) and in conflict resolution with practice on the Attention Network Test (ANT). This finding indicates that methylation may operate on or through genes that influence executive network operation. However, MTHFR T allele carriers showed faster overall RT and conflict resolution. Some children showed an initial improvement in ANT RT followed by a decline in performance, and we found that alleles of the dopamine beta-hydroxylase (DBH) gene were related to this performance decline. These results suggest a genetic dissociation between improvement while learning a skill and reduction in performance with continued practice.

The Cambridge Handbook of Personality Psychology: Development, Health and Personality Change

The Cambridge Handbook of Personality Psychology - Libros de Medicina - Personalidad/Evaluacion y Tratamiento Psicologico - 106,87