Key-peck responses of two pigeons were maintained on variable-interval schedules of food reinforcement in the presence of a stuffed pigeon to study the characteristics of attack induced by that schedule. The mean interval of the schedule was increased from 15 sec to 600 sec in eight steps before an intermediate interval was reintroduced. The principal characteristics of attack were: (1) substantial attack first occurred on a variable-interval schedule of 90 sec in one pigeon and at 180 sec in the other, (2) the highest attack rates occurred on variable-interval schedules of 300 sec and 600 sec, (3) attack rate generally increased to a maximum and then decreased to a lower level across sessions at each schedule, (4) attacks developed a postreinforcement locus across the initial sessions on all schedules and, except on variable-interval schedules of 300 and 600 sec, occurred primarily in the postreinforcement period during extended training, (5) attack rates and key-peck rates were not recovered when the intermediate-length schedules were reintroduced, and (6) attack rate and key-peck rates were negatively correlated. Except for the fact that the maximum attack rates occurred at interfood intervals of 300 and 600 sec, and that attack and key-peck rates were negatively correlated, these findings have counter-parts in experiments with other reinforcement schedules.

The relation between food deprivation and schedule-induced attack was investigated in four White Carneaux pigeons. Attack toward a mirror target was induced by a schedule of reinforcement in which 3-sec food presentations occurred at alternate intervals of 15 and 120 sec (multiple fixed-time 15-sec fixed-time 120-sec schedule). A continuous tone was presented during the 15-sec periods; it was absent during the 120-sec periods. Each pigeon was tested at 65, 80, and 95% of its free-feeding weight in ascending, descending, and ascending orders, respectively. Two relations were apparent; an inverse relation between body weight and rate of attack, and a tendency for rate of attack to increase during the experiment. Reduction or elimination of attack when the mirror was covered with brown paper for some sessions indicated that the results were due neither to changes in activity that might covary with weight nor to habituation to the experimental situation.Key words: attack, deprivation, schedule induced, mirror pecking, pigeonPain-elicited attack occurs when a noxious stimulus, such as an electric shock or a physical blow (e.g. Azrin, Hake, and Hutchinson, 1965;Ulrich and Azrin, 1962) is presented. Schedule-induced attack occurs during certain schedules of food presentation when an appropriate target is present (e.g. Azrin, Hutchinson, and Hake, 1966;Gentry, 1968). Both types of attack have been described in terms of physical contacts, such as biting by rats (Ulrich and Azrin, 1962) and monkeys (Azrin, Hutchinson, and Sallery, 1964;Hutchinson, Azrin, and Hake, 1966), and charging, pecking, and feather pulling by pigeons Cherek, Thompson, and Heistad, 1972;Dove, Rashotte, and Katz, 1974; Flory, 1969a Flory, , 1969bGentry, 1968 less frequently in satiated pigeons than in pigeons maintained at 80% of their freefeeding weights. Other investigations have shown that food deprivation affects the level of attack when attack is elicited by electric shock. For example, the probability of attack following shock is higher in deprived as compared to nondeprived rats (Cahoon, Crosby, Dunn, Herrin, Hill, and McGinnis, 1971). With respect to schedule-induced attack, responding that is maintained by the opportunity to attack decreases as deprivation level decreases from 85 to 100% free-feeding weight (Cherek et al., 1972). They noted that rate of attack showed changes similar to rate of responding to produce a live target pigeon, but the exact relation between schedule-induced attack and deprivation remains unclear, because in their study target availability as well as attack itself varied as a function of deprivation.The present study investigated the relation between deprivation and mean rate and variability of schedule-induced attack. A mirror mounted in conjunction with four microswitches served as the target. Such an arrangement was used previously in the context of multiple fixed-ratio fixed-ratio schedules, and responding on the mirror was functionally and topograplhically similar to responding that results when a live or st...

This study found that the majority of urban adults did not believe that any of the characteristics of children posed to them predisposed a child to abuse. In contrast, 40% of respondents claimed child abuse could not occur in a family like the one in which they grew up. The majority perceived only one characteristic, alcohol abuse, as a characteristic of child abusers. Few respondents (10%) believed that child abusers could not be helped, and 25% were not sure. Adults' perceptions of child abuse and abusers varied by sex, age, socioeconomic status, and whether the respondents had children. The data indicate that there are significant deficits in the respondents' knowledge of child abuse and neglect.