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The manner by which developing children resist interference effects from irrelevant information is examined. Of particular significance are the influence of perceived structure and selective attention on interference. Stimulus response translation is emphasized over perceptual filtering and motor preparation processes in decreasing interference effects in developing children.

A stop signal paradigm in combination with heart rate measures were used to test the hypothesis of deficient inhibitory processing in boys with attention deficit hyperactivity disorder (ADHD). The authors measured the inhibitory process initiated by a stop signal by observing its success, its latency using a horse race model, and its impact on the timing of the heartbeat. Boys with ADHD performed well and showed appropriate psychophysiological changes. Inhibition latencies were longer in the boys with ADHD, particularly those with concurrent oppositional defiant disorder, than in the controls. Cardiac evidence suggested that greater preparation was associated with inhibition failures in controls, but not in the boys with ADHD. Boys with ADHD seem capable of attending carefully to control responses, but this control appears less effective and arguably is more effortful than in other boys.

The possibility that mnemonic search and arithmetic transformation induce transient heart rate (HR) slowing was studied. Transient HR slowing was assumed to result from the inhibition of premature responding during information processing. Twenty young men performed a 2-step reaction time task. Two precues were followed by a choice cue: 2 additional precues and 1 final choice cue. Choice cues were varied to compare spatial and perceptual-motor processing with mnemonic or arithmetic processing. Cardiac interbeat interval and impedance cardiograph measures were taken beat by beat. The preparation for the respond cue was associated with HR slowing followed by HR speeding associated with response initiation. Mnemonic search induced a transient HR slowing before the speeding initiated by the motor response. Arithmetic transformation did not, but processing of the arithmetic series decreased cue-induced transient HR slowing. Mnemonic search may be associated with a psychophysiological inhibition analagous to that observed in perceptual-motor tasks during response selection.

The performance and heart rate changes of children of different age groups who were made to rapidly switch over from one task to another is studied.

The eyes provide important information for decoding the mental states of others. In this fMRI study we examined how reading the mind in the eyes develops across adolescence and we tested the developmental trajectories of brain regions involved in this basic perceptual mind-reading ability. Participants from three age groups (early adolescents, mid adolescents and young adults) participated in the study and performed an adapted version of the 'Reading the Mind in the Eyes task', in which photographs of the eye region of faces were presented. Behavioral results show that the ability to decode the feelings and thoughts of others from the eyes develops before early adolescence. For all ages, brain activity was found in the posterior superior temporal sulcus during reading the mind in the eyes relative to a control condition requiring age and gender judgments using the same eyes stimuli. Only early adolescents showed additional involvement of the medial prefrontal cortex, the inferior frontal gyrus and the temporal pole. The results are discussed in the light of recent findings on the development of the social brain network.