The relation between long-term decrements of the acoustic startle response in rats and the development of freezing behavior during habituation training was examined. Freezing behavior developed over the initial trials of habituation training, and the rate of long-term response decrements was found to be inversely related to the development of freezing. Manipulations (neurological or behavioral)...

Corticotropin-releasing factor (CRF) and norepinephrine (NE) levels are altered in post-traumatic stress disorder and may be related to symptoms of hyperarousal, including exaggerated startle, in these patients. In animals, activation of both systems modulates anxiety behaviours including startle plasticity; however, it is unknown if they exert their actions orthogonally or dependently. We test...

Bilateral ablation of the telecephalon at the level of the anterior commissure blocked reproduction in male paradise fish. Lesioned males performed species typical displays at the start of the spawning trial but thereafter avoided the female, and they did not build nests. All the sham-operated males spawned and built nests. The reaction of the male to a startle stimulus and the rate of operant ...

BACKGROUND Earlier studies have shown that horizontal eye movement (EM) during retrieval of a negative memory reduces its vividness and emotionality. This may be due to both tasks competing for working memory (WM) resources. This study examined whether playing the computer game "Tetris" also blurs memory. METHOD PARTICIPANTS RECALLED NEGATIVE AND POSITIVE MEMORIES IN THREE CONDITIONS: recall ...

This report presents an evaluation of three commercially available fatigue monitors (the Onguard eye closure monitor, a head nodding monitor-Dozer's Alarm, and an analogue of the Roadguard reaction time monitor) based on laboratory testing. The devices showed an ability to detect fatigue in some cases but were not able to maintain alertness and thus prevent performance deterioration. There were...

The current study examined the process of response initiation in a simple reaction time (RT) task using a startling acoustic stimulus (SAS), which has been shown to trigger a prepared movement through an involuntary initiation pathway. The SAS was presented within the RT interval (concurrent with, and 25, 50, 75, 100, and 125 ms following the "go" signal), with the observed response latency use...

BACKGROUND Body dissatisfaction is the most relevant body image disturbance in bulimia nervosa (BN). Research has shown that viewing one's own body evokes negative thoughts and emotions in individuals with BN. However, the psychophysiological mechanisms involved in this negative reaction have not yet been clearly established. Our aim was to examine the emotional and attentional processes that a...

Four experiments examined the disruption of rifle aim by intense noise bursts. In Experiment 1 a trigger pull was followed occasionally by a noise burst. Aiming was disrupted for 1-2 s, an effect that habituated within days and recovered between days. Expected stimuli were less disruptive than were unexpected stimuli. Experiment 2 demonstrated that weak auditory prestimuli 100 ms before unexpec...

Pupillary dilation in response to sound stimuli is well established and is generally considered to represent a startle reflex to sound. We believe that the auditory-pupillary response represents not only a simple startle reflex to sound stimuli but also represents a reaction to stimulation of other sense organs, such as otolith organs. Eight young healthy volunteers without a history of hearing...

Startle reflex modulation by affective pictures is a well-established effect in human emotion research. However, much less is known about startle modulation by affective faces, despite the growing evidence that facial expressions robustly activate emotion-related brain circuits. In this study, acoustic startle probes were administered to 37 young adult participants (20 women) during the viewing...