Adversity in early and mid-adolescence is associated with elevated startle responses to safety cues in late adolescence.

Elevated responding to safety cues in the context of threat is associated with anxiety disorder onset, but pathways underlying such responding remain unclear. This study examined whether childhood/adolescent adversity was associated with larger startle reflexes during safe phases of a fear potentiation startle paradigm (following delivery of an aversive stimulus) that predict anxiety disorders. Participants (N = 104) came from the Youth Emotion Project, a longitudinal study of risk factors for emotional disorders.

Context and explicit threat cue modulation of the startle reflex: preliminary evidence of distinctions between adolescents with principal fear disorders versus distress disorders.

Anxiety and depression are prevalent, impairing disorders. High comorbidity has raised questions about how to define and classify them. Structural models emphasise distinctions between "fear" and "distress" disorders while other initiatives propose they be defined by neurobiological indicators that cut across disorders.

Human fear conditioning and extinction: timing is everything…or is it?

A differential fear conditioning paradigm was used with 107 healthy undergraduate participants to evaluate the effect of conditioned stimulus (CS) temporal properties on fear acquisition and extinction. Two minute duration CSs were used for Day 1 fear acquisition. Participants were randomized to receive either 1, 2, or 4min CS durations during Day 2 extinction.

Elevated responding to safe conditions as a specific risk factor for anxiety versus depressive disorders: evidence from a longitudinal investigation.

The current study evaluated the degree to which startle reflexes (SRs) in safe conditions versus danger conditions were predictive of the onset of anxiety disorders. Specificity of these effects to anxiety disorders was evaluated in comparison to unipolar depressive disorders and with consideration of level of neuroticism. A startle paradigm was administered at baseline to 132 nondisordered adolescents as part of a longitudinal study examining risk factors for emotional disorders.

Modulation of nociceptive and acoustic startle responses to an unpredictable threat in men and women.

The present study examined whether a moderately aversive abdominal threat would lead to greater enhancement in affect- and pain-related defensive responding as indexed by the acoustic startle reflex (ASR) and nociceptive flexion reflex (NFR) in women compared to men. We also predicted sex differences in threat-related autonomic arousal measured by skin conductance responses (SCRs) to acoustic startle and noxious sural nerve stimulation. Unpredictable threat was manipulated by alternating 30-second safe ("no abdominal stimulation will be given") and threat ("abdominal stimulation may occur at anytime") periods.

Gating of sensory information differs in patients with interstitial cystitis/painful bladder syndrome.

Purpose: Altered sensory processing in interstitial cystitis/painful bladder syndrome cases may result from a deficiency of the central nervous system to adequately filter incoming visceral afferent information. We used prepulse inhibition as an operational measure of sensorimotor gating to examine early pre-attentive stages of information processing in females with interstitial cystitis/painful bladder syndrome and healthy controls.

Materials And Methods: We assessed prepulse inhibition in 14 female patients with interstitial cystitis/painful bladder syndrome and 17 healthy controls at 60 and 120-millisecond prepulse-to-startle stimulus intervals.

Brief report: Sensorimotor gating in idiopathic autism and autism associated with fragile X syndrome.

Prepulse inhibition (PPI) may useful for exploring the proposed shared neurobiology between idiopathic autism and autism caused by FXS. We compared PPI in four groups: typically developing controls (n = 18), FXS and autism (FXS+A; n = 15), FXS without autism spectrum disorder (FXS-A; n = 17), and idiopathic autism (IA; n = 15). Relative to controls, the FXS+A (p < 0.

Increased startle responses in interstitial cystitis: evidence for central hyperresponsiveness to visceral related threat.

Purpose: Hypersensitivity to visceral stimuli in interstitial cystitis/painful bladder syndrome may result from enhanced responsiveness of affective circuits (including the amygdala complex) and associated central pain amplification. Potentiation of the eyeblink startle reflex under threat is mediated by output from the amygdala complex and, therefore, represents a noninvasive marker to study group differences in responsiveness in this brain circuit.

Materials And Methods: Acoustic startle responses were examined in female patients with interstitial cystitis/painful bladder syndrome (13) and healthy controls (16) during context threat (application of muscle stimulation electrodes to the lower abdomen overlying the bladder), and cued conditions for safety (no stimulation possible), anticipation and imminent threat of aversive abdominal stimulation over the bladder.

Increased acoustic startle responses in IBS patients during abdominal and nonabdominal threat.

Background And Aims: Visceral hypersensitivity and symptom severity in Irritable Bowel Syndrome (IBS) are both exacerbated by stress. The eye-blink startle response represents a noninvasive measure of central defensive responding. Evidence for central hyperexcitability was studied in IBS patients by examining potentiation of the startle reflex to a nociceptive threat.

Does neuroticism in adolescents moderate contextual and explicit threat cue modulation of the startle reflex?

Background: This study evaluated the relationship between neuroticism (N), a probable risk factor for emotional disorders, and modulation of startle reflexes (SRs).

Methods: One hundred thirty-two adolescents with varying levels of N but without anxiety or depressive disorders were evaluated in contextual cue and explicit threat cue paradigms.

Results: Within the explicit threat cue paradigm, N potentiated SRs more in conditions that were intermediately associated with threat of an aversive biceps contraction than conditions that were the furthest from and conditions that were the closest to the same threat.

Prepulse inhibition in fragile X syndrome: feasibility, reliability, and implications for treatment.

Pharmacological rescue of behavioral, cognitive and synaptic abnormalities in the animal models of fragile X syndrome (FXS) has prompted the initiation of clinical trials of targeted treatments in humans with this condition. Objective, well-validated outcome measures that are reflective of FXS deficits and can be modeled similarly in animal and human studies are urgently needed. A protocol measuring prepulse inhibition (PPI) of the startle reflex, including measures of test-retest stability, was evaluated in 61 individuals with the fragile X full mutation (40 males and 21 females; 19.

Developmental changes in startle reactivity in school-age children at risk for and with actual anxiety disorder.

The present study examined the development of elevated startle reactivity in anticipation of mild anxiogenic procedures in school-age children with current anxiety disorders and in those at-risk for their development due to parental anxiety. Startle blink reflexes and skin conductance responses were assessed in 7 to 12 year old anxious children (N=21), non-anxious children at-risk for anxiety by virtue of parental anxiety disorder status (N=16) and non-anxious control children of non-anxious parents (N=13). Responses were elicited by 28 auditory startle stimuli presented prior to undertaking mild anxiogenic laboratory procedures.

Is aversive learning a marker of risk for anxiety disorders in children?

Aversive conditioning and extinction were evaluated in children with anxiety disorders (n=23), at-risk for anxiety disorders (n=15), and controls (n=11). Participants underwent 16 trials of discriminative conditioning of two geometric figures, with (CS+) or without (CS-) an aversive tone (US), followed by 8 extinction trials (4 CS+, 4 CS-), and 8 extinction re-test trials averaging 2 weeks later. Skin conductance responses and verbal ratings of valence and arousal to the CS+/CS- stimuli were measured.

Baseline and affective startle modulation by angry and neutral faces in 4-8-year-old anxious and non-anxious children.

The present study examined the magnitudes of startle blink reflexes and electrodermal responses in 4-8-year-old high anxious children (N=14) and non-anxious controls (N=11). Responses were elicited by 16 auditory startle trials during a baseline phase prior to an affective modulation phase involving 12 startle trials presented during angry and neutral faces. Results showed significant response habituation across baseline trials and equivalent response magnitudes between groups during the baseline phase.

When the orbicularis oculi response to a startling stimulus is zero, the vertical EOG may reveal that a blink has occurred.

Objective: Startle blink reflexes in humans are typically measured as orbicularis oculi electromyographic activity (ooEMG) in response to startling stimuli. When ooEMG activity cannot be measured, responses are scored as 'zero'. However, inhibition of the levator palpebrae is also involved in every blink.

Differentiating between reflex and spontaneous blinks using simultaneous recording of the orbicularis oculi electromyogram and the electro-oculogram in startle research.

The present study documents the differences between reflex and spontaneous blinks by recording the vertical electro-oculogram (EOG) along with the orbicularis oculi electromyogram (OO-EMG). EOG and OO-EMG were applied without fixation of the head in 15 freely moving children during an auditory startle experiment. Results revealed that the easily-recorded EOG shows the same relationships between orbicularis oculi contraction and velocity of lid movement in startle blinks as the head-constraining methods, e.