Conditioned Orienting and Defensive Responses

Abstract

Physiological responses were recorded while 9 females (Group P) who Feared spiders and 9 who did not (Group N) viewed “neutral” and spider slides in a delayed, differential conditioning procedure. Two different tones were the conditioned stimuli, and 12 neutral and 12 spider slides the unconditioned stimuli. Each CS was 11 sec long. Only Group P showed differential HR conditioning‐anticipatory acceleration to the CS preceding the spider slides (CS+). For both groups, cephalic vasoconstriction was greater to the CS+ than to the CS‐. However, with repeated trials Group P's response to the CS+ became more prolonged, so that by the last block of trials contraction persisted until the end of the CS period. Group N's response, on the other hand, continued to be constriction followed by rapid recovery to the prestimulus level. Although significant electrodermal conditioning did not occur, Group P tended to give larger anticipatory SC. responses to the CS+ than to the CS‐. There was little evidence of somatic‐autonomic coupling on a group basis. When considered along with post‐experimental reports, the results indicate that at least some of the cardiovascular components of the defensive response (DR) are conditionable.

The effect of conscious and non-conscious presentation of biologically relevant emotion pictures on emotion modulated startle and phasic heart rate

“…After this first cardiac deceleration, there was a steeper cardiac acceleration to the unpleasant pictures compared to the neutral or the pleasant pictures. This finding is consistent with those reported by for Generalized Anxiety Disorder (GAD) patients and Hare and Blevings (1975) for participants with a specific phobia, suggesting a motivated inattention to biologically relevant aversive stimulation (Jennings, 1986). This cardiac acceleration after an initial OR has been interpreted as a type of perceptual defense against a feared or threatening stimulus (Lacey, 1967).…”

Neurobiological Mechanisms Underlying the Blocking Effect in Aversive Learning

“…Note that although conditioned HR responses can be both deceleratory and acceleratory, we were specifically interested in the latter as only these have been associated with an increased state of fear (Hodes et al, 1985;Hamm and Vaitl, 1996). Since acceleratory responses have been shown to grow stronger over the course of acquisition (Hare and Blevings, 1975;Fredrikson, 1981), we investigated not only the first 10 trials of acquisition, but also the second 10 trials, where such an effect would be expected to occur. Similar to analyses of SCR, HR changes in response to CSA and CSB (CSY and CSX) were compared, using paired t tests.…”

Emotion processing without awareness: Features detection or significance evaluation?

“…Namely, HR acceleration associated with electrodermal activation is the typical expression of the defense reaction, defined as a global modification of the organism aimed to the rejection of sensory inputs by means of inhibition of perception and facilitation of motor processes (fight and flight). On the other side, HR deceleration joined to moderate electrodermal activation, would reflect a general orienting response, that is a rearrangement of the organism aimed to the intake of sensorial inputs by attention engagement and action inhibition (Graham, 1979).This dichotomic interpretation of autonomic responses (Hare and Blevings, 1975) is at the basis of the "motivational theory of emotion" which claim that every emotional manifestations reflect the triggering of either the appetitive/approach or the aversive/avoidance motivational system (Lang et al, 1997). According to the affective circumplex model (Posner et al, 2005;Gerber et al, 2008), emotions are classified along two independent dimensions, that is valence (the extent to which emotion reflects a negative or positive state of mind) and arousal (the extent to which emotion is associated with an individual sensation of energy or activation state), each subserved by distinct neural system.…”