Fear responses can be eliminated through extinction, a procedure involving the presentation of fear-eliciting stimuli without aversive outcomes. Extinction is believed to be mediated by new inhibitory learning that acts to suppress fear expression without erasing the original memory trace. This hypothesis is supported mainly by behavioral data demonstrating that fear can recover following extinction. However, a recent report by Myers and coworkers suggests that extinction conducted immediately after fear learning may erase or prevent the consolidation of the fear memory trace. Since extinction is a major component of nearly all behavioral therapies for human fear disorders, this finding supports the notion that therapeutic intervention beginning very soon after a traumatic event will be more efficacious. Given the importance of this issue, and the controversy regarding immediate versus delayed therapeutic interventions, we examined two fear recovery phenomena in both rats and humans: spontaneous recovery (SR) and reinstatement. We found evidence for SR and reinstatement in both rats and humans even when extinction was conducted immediately after fear learning. Thus, our data do not support the hypothesis that immediate extinction erases the original memory trace, nor do they suggest that a close temporal proximity of therapeutic intervention to the traumatic event might be advantageous. . In a typical experiment, a neutral conditional stimulus (CS), such as a tone or image, is paired in time with an aversive unconditional stimulus (US), often an electrical shock. After conditioning, the CS elicits a fear state consisting of behavioral, autonomic, and endocrine responses.After conditioning, fear of the CS can be reduced or eliminated with an extinction procedure consisting of repeated presentations of the CS without the aversive US. Extinction is believed to induce new inhibitory learning that suppresses fear expression but leaves the original CS-US memory trace intact (for review, see Myers and Davis 2002). Evidence for this comes mainly from behavioral studies demonstrating that CS-elicited fear can return after extinction, an impossibility if extinction caused erasure of the original association. The most commonly cited behavioral phenomena supporting this inhibitory learning hypothesis are spontaneous recovery (SR), reinstatement, and renewal. In SR, CS fear re-emerges after extinction with the passage of time (Pavlov 1927;Baum 1988;Rescorla 2004). In reinstatement, unsignaled exposure to the US after extinction leads to context-dependent return of CS fear (Rescorla and Heth 1975;Bouton and Bolles 1979a;Westbrook et al. 2002). In renewal, CS fear returns when the CS is presented outside of the extinction context (Bouton and Bolles 1979b;Bouton and King 1983).Despite this evidence for fear recovery, some reports suggest that extinction may induce partial or complete erasure of the CS-US memory trace. Molecular and physiological studies indicate that extinction may depend on phosphatase activity that reverses n...

Phentermine and phentermine-topirimate in addition to diet and exercise appear to be viable options for weight loss in post-RYGB and LAGB patients who experience WR or WLP.

Peroral endoscopic myotomy provides excellent dysphagia relief for patients with achalasia, but is associated with a high rate of reflux on pH testing postoperatively. Subjective symptoms are not a reliable indicator of postoperative reflux. Routine pH testing should be considered in all patients following POEM.

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