The effects of concurrent secondary tasks on the use of imagery in a free recall task

An attempt was made to evaluate Paivio's view that the superior recall of High-I words compared to that of Low-I words can be ascribed to the fact that imagery is available as an additional encoding dimension in the High-I materials. An experiment is reported which investigated the effects of two types of secondary task on the free recall of word lists consisting of equal numbers of items of high and low imagery. One secondary task was intended to prevent the use of imagery during acquisition. Recall of the High-I items was selectively impaired in the presence of the image inhibiting secondary task. As performance on the secondary task improved in some subjects over 3 trials, it was accompanied by improved recall of the High-I words.     

Magnitudes of score differences produced within sessions in a cooperative exchange procedure

Interest centered on maximal score differences produced within sessions during two-party exchange. Subjects chose between earning money independently or through potentially higher-paying exchange. In the exchange option, only one person could produce points for the other on a trial. Because each exchange response (“give”) required the giver to forego earning points independently, the larger the score difference produced (i.e., the further ahead in earnings the other person was put), the greater the reduction in the giver's earnings if the other person did not reciprocate. Results showed that scores were usually equal at the end of each session, and that subjects maintained close equality of scores throughout each session. When a response-cost contingency that punished the alternation of giving was introduced, however, large within-session score differences developed. These large differences continued to be produced after the response-cost contingency was removed. Finally, when subjects were told that the session could end at any moment, score differences were sharply reduced, indicating that production of score differences remained under the control of discriminative stimuli associated with the likelihood of reciprocation. The study suggests that with appropriate procedures, an experimental analysis of behavioral phenomena associated with the concept of “trust” may be possible.     

Uninstructed human responding: sensitivity to ratio and interval contingencies

College students' presses on a telegraph key were occasionally reinforced by light onsets in the presence of which button presses (consummatory responses) produced points later exchangeable for money. One student's key presses were reinforced according to a variable-ratio schedule; key presses of another student in a separate room were reinforced according to a variable-interval schedule yoked to the interreinforcement intervals produced by the first student. Instructions described the operation of the reinforcement button, but did not mention the telegraph key; instead, key pressing was established by shaping. Performances were comparable to those of infrahuman organisms: variable-ratio key-pressing rates were higher than yoked variable-interval rates. With some yoked pairs, schedule effects occurred so rapidly that rate reversals produced by schedule reversals were demonstrable within one session. But sensitivity to these contingencies was not reliably obtained with other pairs for whom an experimenter demonstrated key pressing or for whom the reinforcer included automatic point deliveries instead of points produced by button presses. A second experiment with uninstructed responding demonstrated sensitivity to fixed-interval contingencies. These findings clarify prior failures to demonstrate human sensitivity to schedule contingencies: human responding is maximally sensitive to these contingencies when instructions are minimized and the reinforcer requires a consummatory response.     

Facilitation of letter recognition by an annulus in a metacontrast paradigm

The recognition of a single letter is found to improve when it is surrounded by an annulus in close proximity. This facilitatory effect is obtained only when annulus and target durations are equal and onsets are simultaneous. When the annulus is increased in size, the facilitatory effect is found first to increase in magnitude and then to decline; no interaction between target letter and annulus is observed for large diameter annuli (72'+). The results are interpreted with reference to a lateral inhibitory model of spatio-temporal interactions.     

Shape discrimination in tropical fish

Two experiments are reported using Egyptian mouthbreeders as subjects in which circle/square discriminations were attempted. In Experiment 1, using large stimuli in a maze type situation, no learning was shown by any of the six subjects. In Experiment II, using a conditioned operant technique of nose banging with smaller stimuli, some learning was shown by only one of the five fish. Rapid learning of other discriminations using the square or circle as negative stimuli was subsequently shown.     

The Socratic Augustine

Augustine is both one of the great dogmatic thinkers in our Western tradition and also one of the most Socratic. How can that be? I suggest that Augustine is given to puzzling over questions of the form “How is it possible that p?”– for example, “How is it possible to measure time when no length of time is ever present to be measured?” Moreover, he asks questions of this form even when he is in no doubt that p is the case. (Thus he is in no doubt that we can measure periods of time even though, strictly speaking, no period of time is ever present.) I suggest further that we can learn something about good teaching from studying Augustine's Socratic-style inquiry.     

The K-BIT: A screen for IQ in six diverse populations

Performance data were collected on the Kaufman Brief Intelligence Test (K-BIT) from a total of 196 individuals from six diverse populations. College students did best, followed closely by closed head-injured adults and their controls; the order of performance then was learning-disabled children, psychiatric patients, and finally, neurosurgical patients in the acute stages of recovery.     

Helping the reluctant client to engage in counselling

The reluctant or resistant counselling client is a common though frustrating client for many school counsellors. A number of techniques designed to aid reluctant clients to engage in the process of counselling are described.