Learned taste aversions in rats as a function of delay,speed, and duration of rotation

Rats fed a saccharin solution and then rotated on a turntable showed an aversion to the saccharin solution on later testing. In the first experiment, the rats learned to avoid saccharin with delays of as much as 9 hr between drinking the saccharin and the start of rotation. The second experiment showed that the critical determinant of aversiveness of rotation was number of rotations. The rats avoided saccharin as much after rotation at high speeds for short durations as after rotation at low speeds for long durations.     

Direct visual access in reading for meaning

Two experiments examined whether phonological receding is an obligatory stage in reading for meaning or whether direct access to a word's semantic representation is the general rule. The first study demonstrated that the time to make a semantic decision about a pair of words was much more delayed by misspelling than was the time to make a phonological one. The second study investigated the effect of varying the syllabic length of a word on reaction time in a category decision task. While reaction time varied with the semantic difficulty of the category decision, it generally proved invariant with respect to syllabic length. It is argued that reading for meaning generally uses a direct route from visual form to semantic representation.     

Effects on concurrent performances of a stimulus correlated with reinforcer availability

A multiple schedule was arranged in which each component consisted of two, concurrent variable-interval schedules of reinforcement. A changeover-key procedure was used, and the components of the multiple schedule were distinguished (initially) by the color of the changeover key. During one component of the multiple schedule, the availability of a reinforcer arranged by one of the variable-interval schedules was marked by an exteroceptive stimulus, provided that that variable-interval schedule was not at the time assigned to the main key. During the other component of the multiple schedule, no reinforcer-correlated stimuli were ever presented. During the latter component of the multiple schedule, the distribution of responses and time for the concurrent variable-interval schedules suggested control by the distribution of reinforcements. During the former component, most main-key responses were emitted on the key in the presence of which reinforcer-correlated stimuli were presented. Changeover rate in the presence of that key color was depressed. The discriminative control over the changeover was easily established and was reversible.     

Accountability and team care

Although we normally have no difficulty with holding individuals accountable for the effects of their actions, we are still confused about holding a health care team accountable. I argue that we can hold teams accountable in the same way that we hold individuals accountable. In constructing this argument, I first examine the nature of a “team,” then look at the consequences of team decision and action, in particular, the problem of synergistic decisionmaking. Finally I relate this philosophical discussion to patient care decisions by teams.     

Comparing lesbian and heterosexual couples on the circumplex model: an initial investigation

This study extends the research on the Circumplex Model to a population of lesbian couples. Instruments consisted of a demographic questionnaire, FACES III, and the Family Satisfaction Scale. Lesbian couples reported significantly higher levels of cohesion, adaptability, and satisfaction than did heterosexual couples. Exceptionally high levels of cohesion and adaptability may help lesbian couples function more successfully in a predominantly heterosexual world. Further, women's socialization may predispose female couples to form more cohesive and adaptable relationships than heterosexual couples. This article also emphasizes the cultural relativity of family norms for studies of lesbian and all minority population couples.     

Response restriction and substitution with autistic children.

Few studies to date have examined time reallocation in naturalistic, multiresponse human repertoires when one or more responses are restricted. For this experiment, free-operant baseline levels of six responses were measured for four autistic children. The high-probability responses were made unavailable, one at a time, such that subjects had access to five, four, three, and two responses in successive restriction conditions. A return to the six-response free-operant baseline condition completed the experiment. Results were compared to predictions made by four time-reallocation models. These results were described accurately only by the selective substitution model. Further analyses examined alternative explanations for the individual reallocation patterns obtained. An expanded selective substitution definition is proposed that may characterize orderly patterns observed in multiresponse repertoires under restriction conditions more accurately than the other existing models.     

Information on response requirements compared with information on food density as a reinforcer of observing in pigeons

On a variable-interval schedule, pecking the key to the pigeon's right (observing response) produced red or green displays relating to the delivery of grain and its dependence on pecking the key to the left (food key). During various blocks of sessions, mixed (no stimulus change) schedules including the following pairs of components were temporarily converted by the observing response to their corresponding multiple (correlated stimuli) schedules: variable-interval 60-s, extinction; variable-interval 60-s, variable-time (response-independent) 60-s; extinction, variable-time 60-s. Differences in food delivery maintained substantial rates of responding on the observing key, without regard to pecking requirements on the food key. Although stimuli correlated with differences in the response requirement on the food key maintained higher observing rates than those maintained by uncorrelated stimuli, they were much lower than those based on food. The value of predictive stimuli as reinforcers is determined by the value of the events predicted. In particular, the cost of pecking appears to be low, and this may place limitations on the applicability of energy-based and economic models of behavior.