Excessive avoidance and diminished approach behavior are both prominent features of anxiety, trauma and stress related disorders. Despite this, little is known about the neuronal mechanisms supporting gating of human approach-avoidance behavior. Here, we used functional magnetic resonance imaging (fMRI) to track dorsal anterior cingulate and medial prefrontal (dACC/dmPFC) activation along an approach-avoidance continuum to assess sensitivity to competing appetitive and aversive contingencies and correspondence with behavior change. Behavioral and fMRI experiments were conducted using a novel approach-avoidance task where a monetary reward appeared in the presence of a conditioned stimulus (CS), or threat, that signaled increasing probability of unconditioned stimulus (US) delivery. Approach produced the reward or probabilistic US, while avoidance prevented US delivery, and across trials, reward remained fixed while the CS threat level varied unpredictably. Increasing the CS threat level (i.e., US probability) produced the desired approach-avoidance transition and inverted U-shaped changes in decision times, electrodermal activity and activation in pregenual ACC, dACC/dmPFC, striatum, anterior insula and inferior frontal regions. Conversely, U-shaped changes in activation were observed in dorsolateral and ventromedial prefrontal cortex and bimodal changes in the orbitofrontal and ventral hippocampus. These new results show parallel dorsal-ventral frontal circuits support gating of human approach-avoidance behavior where dACC/dmPFC signals inversely correlate with value differences between approach and avoidance contingencies while ventral frontal signals correlate with the value of predictable outcomes. Our findings provide an important bridge between basic research on brain mechanisms of value-guided decision-making and value-focused clinical theories of anxiety and related interventions.

No abstract

Extinction effects were evaluated in a multiple baseline across behaviors design with 2 boys after just one of several target problem behaviors was observed during a functional analysis. Other target behaviors emerged as extinction was introduced sequentially across all problem behaviors. Results demonstrated an efficient strategy for simultaneously assessing multiple problem behaviors maintained by the same consequence.

The authors analyzed the results of a social validation survey to determine if autism service providers including special education teachers, parents, and administrators demonstrate a preference for the intervention components of Applied Behavior Analysis or Training and Education of Autistic and other Communication Handicapped Children. They also investigated the comprehensiveness of these treatment models for use in public school programs. The findings indicate no clear preference for either model, but a significantly higher level of social validity for components inherent in both approaches. The authors discuss the need for research to define what is meant by comprehensive programming in autism.

No abstract