Reinforcement (Psychology)

The observation of contrast effects (CE) in response
to differential relnforcenent has subsequently elicited a
diversity of experimental results and theoretical interpretations. Adaptation Level (AL ) concepts have provided
a mechanism for integrating such data within a psychophysical
frame-of-reference approach. The application of
this approach to the somewhat neglected area of response-produced
stimuli associated with effort, suggests that
proprioceptive stimuli may be effectively evaluated in a
simllar manner. Following shifts in the amount of effort
required to produce a constant reward magnitude, performance
measures demonstrated positive and negative contrast
effects (PCE; NCE) in relation to an appropriate control
performance. Data analysis suggested that the combined
effects of greater effort and shift conditions tended to
increase resistance to extinction. The findings are not
consistent Kith traditional (e. g., Hull, Spence) concepts
with regard to CE and the influence of effort on performance. It is suggested that such effects are more consistent with a contextual, or frame-of- reference, viewpoint.

Twenty-eight male hooded rats were trained with a time correlated cue called al1 clock. The Ss were divided into four matched groups for the four experimental procedures. The light out group had the time correlated cue removed.
Two groups received 50% reinforcement; one on an alternating schedule, the other on a random basis. The regular group continued training with the clock.
It was predicted that animals under the greatest control of the clock would exhibit the best temporal discrimination. Dew’s notion that schedules and external stimulation provide more control than the immediate effects of reinforcement over behavior was tested. Helson’s adaptation level theory predicted that the two 50% groups would perform similarly.
All four groups were significantly different from each other (p .001) based on the percent correct responses. Animals under the greatest control of the clock had the best temporal discriminations. Dew’s notion was supported. Helson's theory could not account for the differences between the two 50% reinforcement groups.

The purpose of this study was to explore relations between maternal childrearing styles and children's coping styles during mother-child conflict. Mothers reported on six parenting style dimensions: coercive control, overprotective control, emotional control, constructive control, responsiveness, and positive interaction. Children (mean age 12.01 years) reported on seven dimensions of coping during conflict with their mothers: idealization of parent, endorsement of submission, endorsement of aggression, self-blame, self-efficacy, anger reaction, and fear reaction. Few relations between the maternal variables and the child variables were significant, but those that were made sense. For example, positive interaction with the mother predicted low endorsement of aggression toward her, and maternal emotional control predicted self-blaming coping. Further research should examine whether the effects of maternal styles on children's behavior problems (e.g., aggression, depression) are mediated by children's coping styles.

An experiment was conducted to examine whether cannula-fed rats could learn to suppress amphetamine-induced head movements when milk infusion was contingent upon suppression of these stereotyped movements. To test this hypothesis, rats in two cannula-fed conditions, Cannula/No Lick and Cannula/Lick, received injections of amphetamine (2.0 mg/kg) for 42 consecutive days. Pilot data had suggested that suppression of these movements was unlikely to occur unless some other stereotyped behavior (e.g., licking) could be made, hence the availability of a drinking tube in one of the conditions. Although neither group recovered to baseline intake levels, milk intakes measured over 6 consecutive weeks revealed that both groups had recovered from the initial hypophagic effect of amphetamine and had learned to suppress stereotyped head movements in order to receive milk infusion. There was no significant difference between the intakes of the two groups. These findings suggest that instrumental learning may be an appropriate model to describe the development of tolerance to amphetamine-induced stereotyped movements. They also imply that the channeling of one form of stereotyped head movement (e.g., head scanning) into another form (e.g., licking) is not necessary for tolerance to occur.

Following 20 shock-escape training trials, two experimental groups of
rats were reinforced for either running quickly (DRH animals could
preclude shock in the center section of the runway by decreasing their
starting latencies) or for running slowly (DRL animals could preclude
shock in the center section of the runway by increasing their starting
latencies). Results showed that the DRH animals were running consistently
faster than the DRL animals. The results were discussed in
terms of the existing explanations of vicious circle behavior, as well
as in terms of the differential effects of the reinforcement contingencies.

The aversiveness of time-out from maximal FR schedules
of water reinforcement was assessed using rats as Ss. In one
stimulus condition, S could produce or avoid TOs by lengthening
or shortening pauses - after-reinforcement (PARs). In a
second stimulus condition, Ss could similarly produce or
prevent periods of stimulus change (SC). Results indicated
that TO as S[triangle] or as bar retraction were equally aversive.
Ss consistently shortened PARs and maintained the FR reinforcement
contingencies, although no differential effects of
SC conditions were observed. It was concluded that TO is
aversive due to lack of reinforcement availability rather
than to any effects specifically linked with extinction or
cues associated with non-reinforced responding.