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Facilitating generalization of on-task behavior through self-monitoring of academic tasks.

This study (1) examined whether a self-monitoring procedure taught in a laboratory setting would increase independent on-task behavior there and would generalize without further teaching to a classroom setting, and (2) analyzed the durability of the training effects over the course of 5 months for one subject and 10 months for two other subjects. Two multiple-baseline designs, one across three normal and the other across three deviant children, showed that self-monitoring of academic task-completions facilitated on-task responding for all subjects in the generalization (classroom) setting. A subsequent reversal design showed that these effects were durable, in two of the three subjects still available, at least as much as 1 year after commencement of training. This latter design also suggested that one subject who was not maintained by self-monitoring could be supported in on-task behavior by a peer who was maintained by self-monitoring.

Behavior Therapy

Reversal of innate aversions: attempts to induce a preference for chili peppers in rats.

Although humans frequently develop preferences for innately unpalatable bitter or irritant substances, such preferences are extremely rare in animals. An attempt was made to understand the nature of this difference by systematic experiments with laboratory rats, with chili pepper as the unpalatable substance. In parallel with major aspects of the human experience with chili pepper, rats were exposed to it as a flavoring in all their food for periods up to 11 mo from birth, without significant preference enhancement. Gradual introduction of chili into the diet also had no effect, nor did a series of poisoning and safety experiences designed to teach the rats that only chili-flavored foods were safe to eat. A sequence of seven pairings of chili-flavored diet with prompt recovery from thiamine deficiency did significantly attenuate the innate aversion and may have induced a chili preference in at least one case. Extensive experience with chili did not reliably make rats much less sensitive to its oral effects. The only reliable way to eliminate chili aversion in rats is to destroy their chemical irritant sense, which was accomplished in one group of rats. It is concluded that in contrast to humans, it is extremely difficult to reverse innate aversions in rats.

Animals

Strategic withdrawal from cigarette smoking.

Cigarette smoking can be viewed mainly as a psychological habit with accompanying pharmacological and social satisfactions and reinforcements. It is mainly a learned behavior, occurring in response to direct and indirect social pressures. Though each person's smoking habit is individualized, studies show that smokers find at least six psychological satisfactions in the habit: stimulation, handling, relaxation, tension reduction, craving and habit. To quit smoking, the individual must undergo physical and psychological withdrawal. Physical withdrawal symptoms last about a week but it may take months or years to restructure a life without cigarettes. Quitting is a long-term learning process involving a great deal of unconscious, constructive and painful conflict. One can stop smoking if the problem is attacked on a broad front, if one "burns one's bridges" behind him/her and if suitable satisfying alternatives and involvements are discovered. Physical exercise in the form of aerobics is proposed as an especially effective alternative behavior.

Alcohol Drinking

A comparison of responding maintained under second-order schedules of intramuscular cocaine injection or food presentation in squirrel monkeys.

Key pressing by squirrel monkeys was maintained under second-order schedules of either intramuscular cocaine injection or food presentation. Under one schedule, each completion of a 10-response fixed-ratio unit produced a brief visual stimulus; the first fixed-ratio unit completed after 30 minutes elapsed produced the stimulus paired with either cocaine injection or food presentation. Generally, short pauses followed by high rates of responding were maintained within the fixed-ratio units, and responding was positively accelerated over the 30-minute interval. Under another schedule, each completion of a 3-minute fixed-interval unit produced the brief stimulus; completion of the 10th fixed-interval unit produced the stimulus paired with either cocaine injection or food presentation. Generally, short pauses followed by high rates of responding were maintained within the fixed-ratio units, and responding was positively accelerated over the 30-minute interval. Under another schedule, each completion of a 3-minute fixed-interval unit produced the brief stimulus; completion of the 10th fixed-interval unit produced the stimulus paired with either cocaine injection or food presentation. Rates of responding increased within the fixed-interval units, and to a greater extent over the entire 10 fixed-interval units. Patterns of responding depended more on the schedule of reinforcement than on whether cocaine or food maintained responding. Omitting the brief stimuli following all but the last fixed-ratio or fixed-interval units decreased average rates and altered the patterns of responding. Substituting a visual stimulus that was never paired with cocaine or food following all but the last fixed-ratio or fixed-interval units decreased response rates to a lesser extent and did not substantially alter patterns of responding. When the duration of the paired stimulus was varied from .3 to 30.0 seconds, the highest response rates occurred at intermediate durations (1.0 to 10.0 seconds). The manner in which the stimulus changes affected performances depended more on the schedule of reinforcement than on whether cocaine injection or food presentation maintained responding.

Animals

An experimental analysis of the effects of d-amphetamine and cocaine on the acquisition and performance of response chains in monkeys.

In one component of a multiple schedule of food presentation, monkeys acquired a different four-response chain each session by responding sequentially on three keys in the presence of four geometric forms (learning). In the other component, the four-response chain was the same each session (performance). Both d-amphetamine and cocaine, at the higher doses, disrupted the behavior in the learning component; the overall response rate decreased, the overall accuracy was impaired (i.e., percent errors increased), and there was less within-session error reduction. The performance component was generally less sensitive than the learning component to the disruptive effects of both drugs on rate and accuracy. After pre-feeding or during an extended session, the response rate decreased in both components, but accuracy was generally unaffected. When the four discriminative stimuli in both components were removed, the behavior was disrupted to a greater extent in the performance component. The disruptive effects of both drugs on behavior in the learning component were attenuated when the drugs were administered during the session after the response chain had been acquired. It was concluded that the greater sensitivity of the learning component to disruptive drug effects is related to the relatively weak stimulus control and/or the lower rate of reinforcement associated with that component.

Animals

Human mutations in high-confidence Tourette disorder genes affect sensorimotor behavior, reward learning, and striatal dopamine in mice.

UNLABELLED: Tourette disorder (TD) is poorly understood, despite affecting 1/160 children. A lack of animal models possessing construct, face, and predictive validity hinders progress in the field. We used CRISPR/Cas9 genome editing to generate mice with mutations orthologous to human de novo variants in two high-confidence Tourette genes, CELSR3 and WWC1 . Mice with human mutations in Celsr3 and Wwc1 exhibit cognitive and/or sensorimotor behavioral phenotypes consistent with TD. Sensorimotor gating deficits, as measured by acoustic prepulse inhibition, occur in both male and female Celsr3 TD models. Wwc1 mice show reduced prepulse inhibition only in females. Repetitive motor behaviors, common to Celsr3 mice and more pronounced in females, include vertical rearing and grooming. Sensorimotor gating deficits and rearing are attenuated by aripiprazole, a partial agonist at dopamine type II receptors. Unsupervised machine learning reveals numerous changes to spontaneous motor behavior and less predictable patterns of movement. Continuous fixed-ratio reinforcement shows Celsr3 TD mice have enhanced motor responding and reward learning. Electrically evoked striatal dopamine release, tested in one model, is greater. Brain development is otherwise grossly normal without signs of striatal interneuron loss. Altogether, mice expressing human mutations in high-confidence TD genes exhibit face and predictive validity. Reduced prepulse inhibition and repetitive motor behaviors are core behavioral phenotypes and are responsive to aripiprazole. Enhanced reward learning and motor responding occurs alongside greater evoked dopamine release. Phenotypes can also vary by sex and show stronger affection in females, an unexpected finding considering males are more frequently affected in TD. SIGNIFICANCE STATEMENT: We generated mouse models that express mutations in high-confidence genes linked to Tourette disorder (TD). These models show sensorimotor and cognitive behavioral phenotypes resembling TD-like behaviors. Sensorimotor gating deficits and repetitive motor behaviors are attenuated by drugs that act on dopamine. Reward learning and striatal dopamine is enhanced. Brain development is grossly normal, including cortical layering and patterning of major axon tracts. Further, no signs of striatal interneuron loss are detected. Interestingly, behavioral phenotypes in affected females can be more pronounced than in males, despite male sex bias in the diagnosis of TD. These novel mouse models with construct, face, and predictive validity provide a new resource to study neural substrates that cause tics and related behavioral phenotypes in TD.

Preprint

Human mutations in high-confidence Tourette disorder genes affect sensorimotor behavior, reward learning, and striatal dopamine in mice.

Tourette disorder (TD) is poorly understood, despite affecting 1/160 children. A lack of animal models possessing construct, face, and predictive validity hinders progress in the field. We used CRISPR/Cas9 genome editing to generate mice with mutations orthologous to human de novo variants in two high-confidence Tourette genes, CELSR3 and WWC1. Mice with human mutations in Celsr3 and Wwc1 exhibit cognitive and/or sensorimotor behavioral phenotypes consistent with TD. Sensorimotor gating deficits, as measured by acoustic prepulse inhibition, occur in both male and female Celsr3 TD models. Wwc1 mice show reduced prepulse inhibition only in females. Repetitive motor behaviors, common to Celsr3 mice and more pronounced in females, include vertical rearing and grooming. Sensorimotor gating deficits and rearing are attenuated by aripiprazole, a partial agonist at dopamine type II receptors. Unsupervised machine learning reveals numerous changes to spontaneous motor behavior and less predictable patterns of movement. Continuous fixed-ratio reinforcement shows that Celsr3 TD mice have enhanced motor responding and reward learning. Electrically evoked striatal dopamine release, tested in one model, is greater. Brain development is otherwise grossly normal without signs of striatal interneuron loss. Altogether, mice expressing human mutations in high-confidence TD genes exhibit face and predictive validity. Reduced prepulse inhibition and repetitive motor behaviors are core behavioral phenotypes and are responsive to aripiprazole. Enhanced reward learning and motor responding occur alongside greater evoked dopamine release. Phenotypes can also vary by sex and show stronger affection in females, an unexpected finding considering males are more frequently affected in TD.

Animals

Facilitation of memory processing by posttrial morphine: possible involvement of reinforcement mechanisms?

Posttrial administration of 40 mg/kg and 100 mg/kg, but not of 1 mg/kg, of morphine hydrochloride facilitates learning of a one-trial passive avoidance task in drug-naive mice. The effect does not depend on the punishing properties of the morphine injection, since in injection of LiCl (a strong punisher) fails to enhance learning in a similar way. After the establishment of tolerance by several morphone administrations, the 100 mg/kg, but not the 40 mg/kg, dose level resulted in memory facilitation. The data are discussed in connection with the hypothesis that morphine acts directly on reinforcement mechanisms by activating the opiate receptor.

Animals

A parent-implemented early intervention program for preschool children.

The Regional Intervention Program is a data-based, parent-implemented early intervention program providing comprehensive services to parents and their handicapped preschool children in a 26-county area of middle Tennessee. The program's service modules teach parents how to manage their child's behavior and how to teach their child essential prelanguage, language, and self-help skills. The preschool component develops the child's motor, language, and peer-interaction skills in order to prepare him for placement in a preschool in the community. A liaison module conducts follow-up on each family every six months. Several evaluation components ensure that the program is accountable to both the funding source and the families served.

Behavior Therapy

Self-instruction in dentistry: a critique.

Recent activity and interest in self-instruction and programmed self-instruction emerged from studies which demonstrated the central importance of learner response with prompt consequences. Self-instructional procedures in formal education, e.g., teaching machines, were initially designed to be an improvement over conventional show-and-tell instruction in the arrangement of systematic student response, prompt consequences, and student self-pacing. A minority of self-instructional procedures in dentistry reflect that intent. The evidence discussed suggests that dental education may be the worse for that omission. Suggestions for the improvement of self-instructional in dentistry are presented.

Audiovisual Aids

Simulation studies of learning in an informon network.

A single informon reproduces classical conditioning to compound stimuli under a wide range of conditions during reinforcement and non-reinforcement; it also reproduces simple operant conditioning. A network of 210 informons with 8400 simultaneouslly varying pathways has been simulated; it can learn to recognize handprinted numerals. The networks studied must be more richly interconnected before they can reproduce more detailed behaviour of animals.

Animals

Treatment of a retarded child's faeces smearing and coprophagic behaviour.

The daily rearrangement of a profoundly retarded child's routine shower was effective in eliminating his low-frequency faeces smearing and coprophagic behaviour during the late afternoon/early evening part of the day. The effects appeared to generalise such that both types of behaviour were reduced at other times of the day and night. These results are discussed in terms of a social learning framework. A model for analysing the motivations and reinforcing conditions for rectal digging, coprophagy, and smearing faeces is also presented.

Child

Influence of the suspension of continued treatment with flurazepam and amobarbital on two discrimination learning schedules.

The authors have studied the effect of the suspension of chronic treatment with flurazepam and amobarbital on the operant behavior of rats that for the first time were in the presence of two fixed-interval discrimination schedules. With the sound discrimination schedule, the responses emitted by the treated animals had charactistics similar to those of control animals. With the temporal discrimination schedule, though it is not possible to distinguish between learning rates, modifications in the intensity of the effect (increases in lever pressing) indicate that, considering the doses, the action of flurazepam is slight and that of amobarbital clear and statistically significant.

Acoustic Stimulation