Preference for information about shock duration in rats

Abstract

Rats were permitted to control, by means of a changeover response, the amount of time spent in either a "differentiated" or an "undifferentiated" condition. Shock occurred in both conditions on the same variable-time schedule, half of the shocks being short (.75 sec) in duration, the other half, long (5 sec). In the differentiated (informative) condition, all short shocks were preceded by one signal and all long shocks were preceded by a discriminatively different signal. No information about shock duration was available in the undifferentiated condition, as the same signal preceded short and long shocks. A clear and consistent preference emerged for the differentiated condition, i.e., for information about shock duration. The relevance of this finding for theories which attempt to account for the preference-for-signaled-shock phenomenon was discussed.A number of studies have shown that, given a choice between signaled shocks and identical shocks that are unsignaled, rats frequently show a strong preference for the signaled condition (e.g., Badia & Culbertson, 1972;Lockard, 1963;Perkins, Seymann, Levis, & Spencer, 1966). A variety of mechanisms have been suggested to account for this preference. According to the preparatory response hypothesis, the signals enable the animal to engage in "preparatory" responses which serve to reduce the experienced aversiveness of the shocks (e.g., Perkins, 1968). The information (or uncertainty reduction) hypothesis takes the somewhat more general view that any situation that provides information about important environmental events will be preferred (largely because of uncertainty reduction) over a competing situation that contains less information about these same events (e.g., Berlyne, 1960). Finally, the safetysignal hypothesis emphasizes nonsignal periods as the source of control for the preference-for-signaledshock phenomenon. Animals prefer the signaled condition because shock never occurs during nonsignal (discriminable shock-free) periods and, as a consequence, nonsignal periods generate a much lower level of fear than is elicited by comparable nonshock periods in the unsignaled condition (e.g., Seligman & Binik, 1977, pp. 165-180).The validity of these competing interpretations has been the subject of a number of studies, the results of which generally confirm that discriminable shockfree periods are indeed a powerful source of control The present experiment addressed a simple question. Granted that information regarding nonshock periods is a strong source of behavioral control, does information about impending aversive events serve any controlling function at all; i.e., is such information reinforcing? This issue was investigated by providing certain information about the nature of the impending shock in one condition and withholding such information in a second condition. Rats were permitted to control, by means of a "changeover" response, the amount of time spent in one of two, mutually exclusive, conditions, one informative with respect to shock duration, the oth...

Relationships among attention networks and physiological responding to threat

“…That is, cues signaling that danger is imminent give individuals greater opportunity to prepare for danger (e.g., by engaging in distraction or emotion regulation; D'Amato & Safarjan, 1979; Imada & Nageishi, 1982; Perkins, 1968; Sheppes et al, 2015). The relationship observed between executive control of attention and predictable threat responding may therefore indicate that individuals with greater capacity for executive control were better able to down-regulate emotional responding (e.g., through effortful attentional redeployment; Gross & Jazaieri, 2014), but only when the predictability of threat stimuli afforded sufficient opportunity to do so.…”

Effects of predictability of shock timing and intensity on aversive responses

“…It will be important for future studies to extend this finding to other parameters of unpredictability (e.g., duration of aversive event, modality of aversive event, etc.) in order to determine whether unpredictable aversiveness, more broadly defined, is anxiogenic (D Amato and Safrajan, 1979; Imada and Nageiski, 1982). 2…”

Uncertainty, Information, observing

“…. [when] the application of the hypothesis is legitimate" (p. 585), it simply did not apply to the data presented by D'Amato and Safarjan (1979). After ruling out alternative formulations, they concluded with a provisional acceptance of the information hypothesis "at least until an explanation in a true sense is proposed" (Imada & Nageishi,p.…”