| Abstract: | The present study examined the relationship between performance deficits that occur following exposure to uncontrollable stressors and activation of the endogenous opioid system. Subjects were given an injection of saline or naloxone, an opioid antagonist, prior to exposure to 23 min of unpredictable intermittent bursts of noise or silence. Changes in mood were assessed following the injection and the stressor. Performance was measured during and after stressor exposure. Measures of performance following the stressor included a proofreading, an encoding, and a puzzle task. Results replicated previous work on the effects of noise on performance; exposure to noise was associated with performance deficits during and after the stressor. Although naloxone had no effect on performance following the noise, it was associated with greater performance deficits during exposure to the stressor. Further, although all subjects became more hostile, anxious, and depressed following exposure to noise or silence, naloxone improved mood before the stressor began. |
