Emotion regulation in adults may be mediated by frontal cortical activities that adjust attention in response to challenging emotions. We examined event-related potentials across emotional conditions to assess normative patterns and individual differences in cortical mechanisms of emotion regulation in 4-6-year-olds. The children viewed pictures of angry, neutral, and happy faces during a Go/No-go task. Angry faces generated the greatest (frontocentral) N2 amplitudes and fastest N2 latencies, and happy faces produced the smallest amplitudes and slowest latencies. Frontal electrodes showed larger N2s to angry faces in the Go condition. The P3b was also largest for angry faces. More fearful children showed faster latency N2s to angry faces. These results are interpreted in terms of early-developing mechanisms for regulating anxiety and processing emotional information.

Background Sub-anesthetic doses of the NMDA antagonist ketamine have been shown to model the formation and stability of delusion in human subjects. The later has been predicted to be due to aberrant prediction error resulting in enhanced destabilization of beliefs. To extend the scope of this model, we investigated the effect of administration of low dose systemic ketamine on memory in a rodent model of memory reconsolidation. Methods Systemic ketamine was administered either prior to or immediately following auditory fear memory reactivation in rats. Memory strength was assessed by measuring freezing behavior 24 hours later. Follow up experiments were designed to investigate an effect of pre-reactivation ketamine on short-term memory (STM), closely related memories, and basolateral amygdala (BLA) specific destabilization mechanisms. Results Rats given pre-reactivation, but not post-reactivation, ketamine showed larger freezing responses 24 hours later compared to vehicle. This enhancement was not observed 3 hours after the memory reactivation, nor was it seen in a closely related contextual memory. Prior inhibition of a known destabilization mechanism in the BLA blocked the effect of pre-reactivation ketamine. Conclusions Pre- but not post-reactivation ketamine enhances fear memory. These data together with recent data in human subjects supports a model of delusion fixity that proposes that aberrant prediction errors result in enhanced destabilization and strengthening of delusional belief.

No abstract

No abstract