Stimulus control of behavior during the postreinforcement pause of FI schedules

Abstract

Pigeons were given the opportunity to terminate certain segments of fixed intervals by pecking a control key. When 3D-sec segments of negative and positive stimuli alternated across the interreinforcement interval (Experiment 1), most birds terminated a large proportion of negative segments. However, few control-key responses were made during the negative segment immediately following food presentation. Under schedules during which only one negative segment was programmed, during the first 30 sec of 1-min intervals (Experiment 2), control-key responses, when they occurred at all, were made after several seconds of the interval had elapsed. Similar findings were obtained when a peck on the control key merely changed the color on the food key (Experiment 3). These findings suggest that the postreinforcement extinction state (Schneider, 1969)during fixed-interval schedules consists of two phases: an immediate postreinforcement inhibitory phase, followed by a second phase during which a control-key response may occur. These two phases and their associated behavior may be related to Staddon's (1977) distinction between interim and facultative activities.The behavior of pigeons on fixed-interval (FI) schedules of reinforcement develops a characteristic pattern, the FI scallop (Ferster & Skinner, 1957). Toward the end of an interreinforcement interval, a high rate of keypecking, the terminal response, is usually observed, while at times immediately following food presentation, other behaviors, called interim activities, are likely to occur (Staddon, 1977;Staddon & Simmelhag, 1971). The period during which behavior other than the required operant (terminal response) occurs is called the postreinforcement pause and is typically a constant proportion of the interreinforcement interval (Schneider, 1969 havior other than the terminal response on either FI or mu/t EXT VI schedules, some researchers have suggested that pigeons find stimuli associated with both extinction and the early portions of FI schedules aversive. Terrace (1966) reported that birds showed "emotional" responses, such as wingflapping, during the extinction component of a multiple schedule, and Azrin et al. (1966) found that pigeons would attack a target bird during extinction. Richards and Rilling (1972) obtained similar target-attack behavior in pigeons on an FI 90-sec schedule. Most of the attacks were recorded during the first half of an interreinforcement interval.Birds will also respond to terminate visual stimuli associated with both FI and extinction schedules. Brown and Flory (1972) found that pigeons would respond to change the color of the key light and turn off the houselight during fixed intervals ranging from 30 to 960 sec, although interval duration was not shortened by this response. Rilling et al. (1%9) found that pigeons would peck a key to produce a blackout and thus escape from a stimulus associated with extinction. Honig and his associates (Honig et al. , 1972; Leyland & .Honig, 1975) showed that birds would learn a control-key respo...

The Role of Intermittent Food in the Induction of Attack in Pigeons

“…In general, there was a burst of attack following a food delivery regardless of whether or not food signaled a period of no food, although in Experiment II the rate of postfood attack for the RT group was less than for the FT group. This postfood burst of attack is consistent with suggestions that there are aftereffects of reinforcement (Innis & Honig, 1979;Solomon & Corbit, 1974) and that schedule-induced attack is induced by interrupted access to or the withdrawal of a reinforcer (e.g., Azrin et al, 1966;Hutchinson, 1973). The present results also support the idea that schedule-induced behavior may reflect the elicitation of arousal by the reinforcer (Killeen, 1975).…”

“…The induction of postreinforcement attack by inter-101 1981, 36., [101][102][103][104][105][106][107][108][109][110][111][112][113][114][115][116][117] mittent reinforcement alone would be consistent with suggestions by Azrin et al (1966), Hutchinson (1973), and others (Gentry, 1968;Rilling, 1977;Rilling & Caplan, 1975) that the termination or withdrawal of a reinforcer induces aggression. This view is compatible with the proposal that there are aftereffects of reinforcers (Innis & Honig, 1979;Solomon & Corbit, 1974) and that schedule-induced behavior, including attack, may reflect motivational sequelae of reinforcers (Killeen, 1975). Millenson, Allen, and Pinker (1977) and Lashley and Rosellini (1980) have examined this question with regard to schedule-induced polydipsia in rats and have found that constant-probability food schedules were effective in inducing polydipsia in fewer rats than schedules with variations in reinforcer probability.…”

Typical Delay Determines Waiting Time on Periodic‐food Schedules: Static and Dynamic Tests

“…We used the same general procedure as before; differences included a third procedure, the clamped condition, for which food delay, T, was complementary to waiting time, t: t + T = C, a constant, so that interfood interval was independent of t for all t < C (this procedure resembles what has been called a conjunctive fixed-ratio 1, fixed-time schedule: Shull, 1970;Staddon & Frank, 1975; see also Innis & Honig, 1979). Also, conditions were changed daily, rather than remaining constant across several days.…”

Organization of attack and other behaviors of White King pigeons exposed to intermittent water presentations

“…They have noted that during the postreinforcement pause following response-contingent food reinforcement, pigeons are unlikely to engage in pecking behavior that initiates a fixed-interval period (Shull, 1970), terminates a reinforcement schedule (Brown & Flory, 1972), or increases reinforcement rate. Although the results of this experiment cannot account for the post-reinforcement inhibition of keypecking, they do rule out the hypothesis (Innis & Honig, 1979) that, following food reinforcement, pecks that topographically resemble feeding behavior are inhibited. This is not the case, since vigorous feeding-like pecks readily occur immediately following food reinforcement when those pecks are directed toward the head of a conspecific target located away from the reinforcer dispenser.…”

“…Results obtained with food-reinforced subjects bear on another issue raised by Innis and Honig (1979). They have noted that during the postreinforcement pause following response-contingent food reinforcement, pigeons are unlikely to engage in pecking behavior that initiates a fixed-interval period (Shull, 1970), terminates a reinforcement schedule (Brown & Flory, 1972), or increases reinforcement rate.…”