Determinants of tonic and phasic reactions in transswitching

Forty-eight college students were assigned randomly to four groups in a 2 × 2 factorial arrangement of phasic conditional stimuli (samevs. different) and tonic conditional stimuli (samevs. different) to receive 2 days of classical conditioning with a transswitching procedure. Tonic stimuli were a 5-minute projected white triangle or circle; phasic stimuli were a 5-second red or green square superimposed over the tonic stimuli. There were six tonic stimulus segments each day, separated by 20-second periods of no stimulus, three containing six trials of the phasic stimulus paired with shock and three containing six trials of the phasic stimulus alone, in the counterbalanced order. Tonic responding at the onset of the tonic stimuli or during brief periods following its onset were recorded, along with phasic responses to the phasic stimuli. Responses included magnitude of skin conductance responses, frequency of unelicited skin conductance responses, and tonic heart rate. Both skin conductance measures of responding to the tonic stimuli differentiated significantly between positive and negative tonic segments during Day 2, but only in the group with two different tonic stimuli and one phasic stimulus (“standard” transswitching). This supported the hypothesis that tonic stimulus differentiation would be absent when two different phasic stimuli were present. The heart rate data did not support this hypothesis, showing tonic differentiation in both groups with two tonic stimuli. Phasic differentiation controlled by the different phasic stimuli was observed on Day 1; on Day 2, phasic differentiation was present only in the group with two tonic and one phasic stimuli and the group with one tonic and two phasic stimuli. The results were interpreted to mean that temporal contiguity between the tonic stimuli and shock or no shock is not sufficient to establish tonic response differentiation in transswitching.     

Social reinforcement as a determinant of performance, performance expectancy, and attributions

The effects of positive, negative, and nonreinforcement were examined during performance of a fine motor task to observe any expectancy and performance differences. Female high school subjects first learned the task and then were given a series of 30 trials in which social reinforcement was administered noncontingently. Positive social reinforcement had a significant effect on performance, while both positive and negative reinforcement had significant effects on expectancy. In addition, disparate attributions were made by each treatment group.     

Cardiac conditioning in the white rat with food presentation as unconditional stimulus

Pavlovian conditioning of heart rate in the white rat was attempted using milk presentation as reinforcement, and with both trace and delay paradigms. Delay conditioning produced positive results that were statistically significant, whereas trace conditioning exhibited the same trends but did not reach statistical significance. In both cases, CR had the same direction as UCR to milk (acceleration of heart rate) and opposite to the unconditional reaction to CS. Extinction and reconditioning were both accomplished. Some indications of complex response interactions were noted in the occurrence of the cardiac CR on conditioning trials where the instrumental response to the UCS (drinking) eventually occurred, as against the absence of cardiac CR on trials where the instrumental response did not occur. The existence of such interactions was also indicated by the fact that CR on individual trials within any single session could vary in direction between acceleration and deceleration, although averages might be stable.     

Conditioned suppression of the proboscis-extension response in young, middle-aged, and old Drosophila melanogaster flies: acquisition and extinction

Young (7 days old), middle-aged (30 days old), and old (50 days old) Drosophila melanogaster males were used in an inhibitory conditioning of the proboscis-extension response. Two reinforcement schedules were applied, constant vs. partial. Partial reinforcement increased the number of trials needed to reach the learning criterion to the same extent in all age groups. Young flies needed fewer trials to reach the criterion than both middle-aged and old flies, which did not differ from each other. Extinction was delayed in the partial reinforcement groups by the same amount in all age groups. The slowest rate of extinction was observed in the old group and the fastest for the middle-aged flies. The results are discussed in connection with hypotheses that consider extinction an index either of behavioral rigidity or of strength of the initial learning.     

Effects of exogenous changes in heart rate on facilitation of thought and resistance to persuasion.

Two experiments were conducted to examine the effects of an accelerated heart rate on information processing and resistance to persuasion. Experiment 1 addressed the effects on cognitive performance of manipulating heart rate exogenously for brief periods of time. Fourteen subjects wearing implanted demand-type cardiac pacemakers performed reading comprehension and sentence generation tasks while their heart rate was either accelerated or not accelerated. Results revealed that performance was better when heart rate was accelerated than when it was not accelerated. Experiment 2 addressed the effects on counterargumentation and resistance to persuasion of manipulating heart rate using the cardiac-pacing technique employed in Experiment 1. Subjects read highly involving counterattitudinal communications while their heart rate was either ostensibly or actually accelerated. Accelerated heart rate resulted in the generation of more total thoughts and counterarguments than did basal heart rate; resistance to persuasion was related significantly to the number of counterarguments generated. The methodology used provides a means by which social psychologists can study the effects on social processes of actual but unperceived changes in physiological processes.     

Conditioned inhibition from incomplete reductions in the probability of reinforcement

Five experiments, all using appetitive, discrete trial operant conditioning, studied the properties of a stimulus that signalled a reduction in the probability of reward. Discriminations were trained in which reinforcement was available on 100% of trials signalled by a tone, but only on some occasions when the tone was presented simultaneously with a light. The properties of the light were assessed in summation tests with a clicker. The first two experiments established that if the tone-light compound signalled reinforcement on only 25%, 33% or 50% of trials the light acted as a discriminative inhibitor, suppressing responding maintained by the clicker. In these experiments reinforcement had been available on 86.7% of clicker trials during initial training. Experiments 3, 4 and 5 examined further the properties of the light after animals had been trained on a discrimination where reinforcement was available on 50% of trials signalled by the tone-light compound. The light was evaluated in a summation test with a clicker, which had signalled only a 25% or 15% probability of a reinforcement. In this instance, the light did not suppress the responding maintained by the clicker. Instead, the light acted as an excitatory discriminative stimulus to enhance that responding. This dependence of the properties of the light on the reinforcement history of the clicker poses problems for most contemporary models of inhibitory performance.     

Treadmill Gait Analysis Characterizes Gait Alterations in Parkinson's Disease and Amyotrophic Lateral Sclerosis Mouse Models

The effect of anxiety on learning and performance of a complex motor task was determined. In addition the effects of two stressors—competition and failure—and the interactions between these stressors and anxiety were investigated. 40 high and 40 low anxiety Ss (selected by the Taylor Manifest Anxiety Scale) learned and performed a coincident timing task. Competition was presented by offering the Ss a monetary reward for the best performance, while failure was manipulated by giving false knowledge of results and indicating that the performance level was inferior. Results showed that Ss low in anxiety performed significantly better than Ss high in anxiety during the initial learning of a complex motor task. No difference was found between Ss extreme in anxiety once the task was well-learned. Competition and failure did not affect performance or interact with the anxiety level of Ss.     

COMPARISON OF MODELLING AND REINFORCEMENT PROCEDURES IN INCREASING QUESTION-ASKING OF MILDLY RETARDED CHILDREN1

Questioning is an important skill, particularly for retarded children with deficits in accumulated information. Recent strategies for modifying a variety of verbal behaviors have included both token reinforcement systems and modelling procedures. However, the relative effectiveness (i.e., the rate of behavior change) of certain reinforcement procedures, especially with low base-rate behavior (used alone) have recently been questioned. The present study, using an ABAB design, compared the effect of a Token reinforcement system, a Trainer-Model procedure, and a combination of the two procedures on increasing the rate of question-asking. Each condition was in effect for six sessions. Groups of four mildly retarded children (mean age: 10.1 yr) were prompted to ask questions about large photographs, and each of their questions was immediately answered. For the Model group, the Trainer modelled four questions for each subject for each photograph. For the Token group, each question earned the subject a point, which was exchangeable after the session for various items (e.g., candy, ice cream) from a “store”. For the Modelling plus Token group, the procedures were combined. The Model and the Control groups were yoked to receive the same amount of candy as the Token and the Model plus Token groups for behaviors other than question-asking (i.e., being polite). The results indicated that during Baseline conditions, performance across groups was comparable and that the performance of the Control group did not change across time. The Model procedure had only minimal effects on the rate of question-asking, while both the Model plus Token and the Token groups showed significant performance increments. The only significant difference between the Model plus Token and the Token groups was a faster rate of increase early in the first Training condition for the Model plus Token group. This difference, and the low level of performance change for the Model group, was interpreted as suggesting a facilitory effect of modelling procedures on reinforcement contingencies. The discrepancy between previous findings showing relatively minimal changes following reinforcement of low base-rate responses and the present results were discussed in terms of various procedural differences. Educational implications of the present results were also discussed.     

Differential reinforcement of lever-press durations: Effects of deprivation level and reward magnitude

Three experiments investigated the performance of rats on a task involving differential reinforcement of lever-press durations. Experiment 1, which employed a discrete-trials procedure, manipulated deprivation level between subjects and reward magnitude within subjects. The minimum lever-press duration which would result in reward was varied from .4 to 6.4 sec. It was found that low deprivation resulted in longer mean durations and less response variability at the higher criterial values than did high deprivation. The magnitude of reward was not found to affect performance. Experiment 2 manipulated reward magnitude between subjects while holding deprivation level constant, and used the same general procedures as in Experiment 1. Small reward resulted in longer mean lever-press durations and less variability in responding than did large reward at the higher criterial values. The intertrial intervals were omitted in Experiment 3 in which deprivation level was varied between subjects and reinforcement was delivered only for response durations extending between 6.0 and 7.6 sec. Low deprivation resulted in longer mean lever-press durations and less response variability than did high deprivation, but the probability of a rewarded press duration did not differ between groups. The results overall are consistent with the hypothesis that low deprivation and small reward magnitude lead to weaker goal-approach responses and, hence, to less competition with lever holding. The deprivation and reward magnitude manipulations did not appear to influence lever holding performance by affecting the ability of animals to form temporal discriminations.     

Evidence of improved shooting precision in biathlon after 10 weeks of combined relaxation and specific shooting training

The aim of this study was to test the hypothesis that a combined relaxation (applied tension release, ATR) and specific shooting training regimen may enhance shooting ability of biathlon athletes. Seven biathletes of high national level were randomized into an experimental group (age 20 ± 5 years; Vo2max 60 ± 8 mL kg(-1) min(-1)) and were asked to add this special training intervention to their regular training for 10 weeks, while five other biathletes served as controls (age 19 ± 2 years; Vo2max 57 ± 10 mL kg(-1) min(-1)). The shooting ability of the subjects was assessed before and after the intervention at rest and after roller skiing on a treadmill in a laboratory-based competition simulating assessment. After the intervention period, the experimental group demonstrated a significantly enhanced shooting performance compared to the control group. No changes in Vo2max or in heart rate and Vo2 responses were observed before and after the intervention in either group and there were no differences between the groups in these parameters. Thus, the preliminary conclusion is that a combination of ATR and specific shooting training seems to be instrumental in enhancing the shooting performance in biathlon.     

Memory for Movement Sequences in Gymnastics: Effects of Age and Skill Level

The authors studied the performances of 8- to 13-year-old skilled (n = 30) and less skilled (n = 30) gymnasts on a gymnastics routine recall task by examining the role of memorization strategies and imagery ability. Subjects had to reproduce 3 movement sequences presented on videotape. The number of trials needed to achieve correct recall, the strategies employed, and the subjects' imagery ability were analyzed. Recall performance improved with age and skill level. Movement labeling was the most prevalent strategy used; its frequency increased with age, although it did not lead to better recall performance. Performance was higher, however, among subjects with better imagery skills. The role of strategy development in the age-related improvement in memory performance was not clearly demonstrated. The effect of skill level is interpreted in terms of knowledge bases and kinesthetic movement encoding.     

Determinants of instrumental extinction in terrestrial toads (Bufo arenarum)

Previous research in a water-reinforced instrumental training situation with toads (Bufo arenarum) has shown that performance in both acquisition and extinction is poorer after partial, rather than continuous reinforcement training. In Experiment 1, the performance of a group receiving 24 trials on a 50% partial reinforcement schedule was poorer in acquisition and extinction than that of continuously reinforced groups matched for trials or reinforcements. However, partially reinforced toads extinguished at the same rapid rate as a continuously reinforced group that received training only on the days in which the partial toads received water reinforcement. In Experiment 2, extinction was faster after 10 reinforced acquisition trials than after 30 trials. This evidence suggests that the deleterious effects of partial reinforcement in toads can be explained by a combination of two factors, namely, the distribution of reinforced trials across days and the total number of reinforcements.     

Stereotype threat undermines intellectual performance by triggering a disruptive mental load

Research on stereotype threat has repeatedly demonstrated that the intellectual performance of social groups is particularly sensitive to the situational context in which tests are usually administered. In the present experiment, an adaptation of the Raven Advanced Progressive Matrices Test was introduced as a measure of cognitive ability. Results showed that individuals targeted by a reputation of intellectual inferiority scored lower on the test than did other people. However, when the identical test was not presented as a measure of cognitive ability, the achievement gap between the target and the control group disappeared. Using heart rate variability indices to assess mental workload, our findings showed that the situational salience of a reputation of lower ability undermined intellectual performance by triggering a disruptive mental load. Our results indicate that group differences in cognitive ability scores can reflect different situational burdens and not necessarily actual differences in cognitive ability.     

Training of instrumental responses in dogs socially reinforced by humans

The motivational bases of the social reinforcement in human-dog relations were examined. In experiment I, performed on seven dogs, it was found that dogs were able to learn and sustain the natural responses of sitting, paw extension, and lying prostrate to conditional stimuli in the form of vocal commands reinforced only by social rewards given by the experimenter, such as petting and vocal encouragement. Overtraining did not produce deterioration of performance but, on the contrary, the continual decrease of latencies. It was evidenced that tactile stimulation plays an important role in social reward. In experiment II, instrumental responses to the auditory conditional stimuli were elaborated in two groups of dogs. The first group (nine dogs) was reinforced by food, and the second group (eight dogs) was reinforced exclusively by petting. A similar course of learning and level of performance during overtraining sessions in both groups indicated that petting serves as a good reinforcement, with rewarding value comparable to that of food reinforcement. It is suggested that a strong rewarding effect of pleasurable sensory stimuli occurs in the formation of the bond between dog and human and in the learning of different tasks.     

Opiates and homing

Beginning at 15 days of age. Long-Evans rat pups were trained to run toward their home cage in a T-maze task. Morphine (.5-1.0 mg/kg sc) slowed initial acquisition running times but did not change the number of trials required to learn the position habit. Morphine markedly impeded extinction of the homing behavior. Opiate-treated animals ran as accurately and as quickly toward home on the 12th day of extinction as on the first (10 trials given per day). Conversely, naloxone (1 mg/kg sc) reduced resistance to extinction. The morphine effect was not state-dependent since the drug also impeded extinction in animals that had acquired the task under saline. The morphine effect was blocked by naloxane, which indicates that the increased resistance to extinction was due to an opiate receptor effect. These results indicate that morphine has a strong capacity to sustain a social habit in the absence of reinforcement.     

Individual differences in imagery vividness and voluntary heart rate control

Dispositional differences in imagery vividness may account partially for the large individual differences in learning heart rate control. Based upon scores on the Betts QMI Vividness of Imagery Scale, 10 subjects were defined as a high imagery group and 10 subjects were defined as a low imagery group. All subjects were instructed to try to alter their heart rate as indicated by appropriately labeled lights. Six increasing, six decreasing and six rest, 45-sec trials were presented. During the trials, visual heart rate feedback was provided by a digital voltmeter. The dependent measure was computed by subtracting the mean of the last 5 beats of a 15-sec intertrial interval from the mean rate per trial. Results indicated that subjects were able to significantly raise and lower heart rate relative to rest trials. Furthermore, high imagery subjects demonstrated significantly larger changes than low imagery subjects on increase trials but not on decrease trials. Subjects in both groups typically reported using more specific images for increasing heart rate than for decreasing heart rate. These data suggest that dispositional differences in imagery vividness may have contributed to the differential performance of the two groups during the increase task.     

Increasing purposeful activity of severely and profoundly mentally-handicapped adults

A time-series reversal design was used to evaluate the effect of a ‘room manager’ procedure on the level of purposeful activity of severely and profoundly mentally-handicapped people in a residential home. The room manager procedure consisted of systematic prompts to participate in recreational activity and social reinforcement contingent on engagement. Data were collected on group and individual client behaviour and two measures of staff performance were taken to assess whether the procedure was implemented consistently across subjects and in line with the experimental design. The results showed that, as well as a group of subjects who engaged at a higher level during the room manager condition, there were consistently ‘high-engaging’ and ‘low-engaging’ groups, reflecting in part the general level of ability of the subjects. However, data on the independent variables show that the the contingency of staff contact did not vary across conditions and it cannot therefore be assumed that these subjects would not respond to the intervention. Some limitations of the procedure as used are discussed, and areas where further work is needed are indicated.     

Effects of outcome feedback on perception of dispositional and situational control in motor skill performance

This experiment investigated the effects of outcome feedback and the type of situation on perception of dispositional and situational control over motor skill performance. The experimental design was a 2 × 2 × 2 (type of situation × past outcome × present outcome) factorial. The subject competed with an opponent (a confederate) on ten pretest and ten test trials of a motor maze task. The results showed that both past and present success enhanced perception of dispositional control in terms of personal ability whereas failure (past and present) facilitated perception of situational control in terms of the opponent's ability. The type of situation had negligible influence on the subject's control perception of their motor performance. The results were viewed as having important implications for studying the effects of social reinforcement and outcome feedback on motor performance and thus for understanding why outcome feedback sometimes increases and sometimes decreases motor performance.     

Memory for Movement Sequences in Gymnastics: Effects of Age and Skill Level

The authors studied the performances of 8- to 13-year-old skilled (n = 30) and less skilled (n = 30) gymnasts on a gymnastics routine recall task by examining the role of memorization strategies and imagery ability. Subjects had to reproduce 3 movement sequences presented on videotape. The number of trials needed to achieve correct recall, the strategies employed, and the subjects' imagery ability were analyzed. Recall performance improved with age and skill level. Movement labeling was the most prevalent strategy used; its frequency increased with age, although it did not lead to better recall performance. Performance was higher, however, among subjects with better imagery skills. The role of strategy development in the age-related improvement in memory performance was not clearly demonstrated. The effect of skill level is interpreted in terms of knowledge bases and kinesthetic movement encoding.     

Electroencephalographic correlations of temporally spaced responding and avoidance behavior

This study was undertaken to determine whether any EEG changes occurred during a multiple schedule of reinforcement consisting of repeated periods of avoidance behavior, a time-out (TO) period, and a period of differential reinforcement of low rates (DRL). The two monkeys were permanently implanted with bipolar electrodes in various subcortical areas. The EEG was recorded from these electrodes for several weeks before any behavioral training was undertaken. Training was then begun in the multiple schedule, and EEG recordings were taken frequently throughout the training period. When a stable performance level was achieved, drugs (dl-amphetamine and sodium pentobarbital) were introduced which disrupted the DRL performance but had little or no effect on avoidance behavior. The EEG recordings continued throughout these drug studies.

The data indicate that the marked behavioral differences noted in each component of the schedule were not reflected in the EEG. However, the EEG did correlate with the general level of alertness of the animals during the various components. The drugs which differentially affected the behavior in the components of the schedule did not differentially affect the EEG, but they did change the brain-wave activity equally in all components. Finally, EEG changes correlated with the complex motor response of lever pressing were not observed.