Extradimensional transfer in the easy-to-hard effect

In three experiments analyzing determinants of the easy-to-hard effect, pigeons acquired a hard discrimination after training on other problems. Intradimensional pretraining resulted in immediate transfer to the hard discrimination. Extradimensional pretraining consistently did not produce immediate transfer but did facilitate learning rate. In Experiment 1, the compounding of cues from an easy extradimentsional discrimination with those from the hard discrimination resulted in the former overshadowing the latter. When different types of extradimensional discriminations were introduced in Experiments 2 and 3, the degree of transfer was not proportional to the similarity in incidental background cues across problems. The findings indicate that in the easy-to-hard effect: (a) intra- and extradimensional mechanisms jointly contribute to the development of stimulus control, (b) intradimensional transfer is more consistent with the gradient-interaction model than the selective attention model, and (c) extradimensional transfer is better accounted for by the construct of general attentiveness rather than by the neutralization of background cues.     

The effects of S-R uncertainty in the PRP paradigm: A reply to Kantowitz

Karlin and Kestenbaum (1968) reported a series of apparently complex interactions between S-R uncertainty and RT in an experiment using the psychological refractory period paradigm. McLeod (1977) showed that these effects could be predicted by a parallel processing limited capacity model. Kantowitz (1978) criticised that paper on the grounds that it paid insufficient attention to the predictions of response conflict theory and made no mention of errors.It will be shown (a) that response conflict theory, as described by Kantowitz, fails to predict the effects found by Karlin and Kestenbaum (b) that the comments about errors miss the point of McLeod (1977) (c) that in his final section Kantowitz falls into an old trap which awaits the unwary analyser of PRP data.     

Acquired aphasia with convulsive disorders in children: a case study with a seven-year follow-up.

In a 7-year follow-up a case of the “syndrome of acquired aphasia with convulsive disorder” is described. In particular, attention is paid to EEG patterns and linguistic analysis. Although seizures have been controlled medically and EEG abnormalities have tended to improve, no close parallel improvement has been observed in the patient's language disorders.     

Discriminative vocal conditioning in rhesus monkeys: Evidence for volitional control?

Both emotional and volitional systems are invoked in explaining the control of human vocalizations, but vocal behavior of nonhuman primates is often believed to be totally under emotional control. Monkeys' poor performance on conditioning tasks, especially discriminative conditioning of vocalization (DCV), has been cited as evidence against volitional control. In Experiment 1, rhesus monkeys failed a DCV task in which food was given for vocalizations emitted during an arbitrary visual stimulus, but in Experiment 2, monkeys showed clear discriminative performance when an otherwise comparable shock-avoidance DCV procedure was used. This evidence that monkeys possess some degree of volitional control has implications for the relation between animal vocalizations and the origin of human speech.     

Extraversion and the orienting reaction habituation rate to visual stimuli

Eysenck's (1967) proposal that introversion is characterized by increased levels of activity in the cortico-reticular loop was treated in a series of experiments which compared high, middle, and low extraversion groups on the basis of OR habituation rate to visual stimulation. Generally, introverts were observed to have longer OR habituation rates to chromatic and word stimulation than extraverts as evidenced by cardiac, electrodermal, and vasomotor indices of habituation rate, a result which endorses Eysenck's hypothesis. Results are also discussed from the standpoint of individual differences in autonomic response.     

The effects of didactic classroom instruction versus field exposure on career maturity

This study tested two types of career training (field exposure and didactic classroom) to determine which is more effective in bringing about the development of career maturity. Forty-six first-year Upward Bound students were assigned to either a field exposure or a didactic group by the use of a stratified random assignment technique. A pretest/post-test design was utilized with the Career Maturity Inventory as the data-collecting instrument. The data were analyzed by analysis of covariance. The results of the study indicate that field exposure career training is an effective method to increase career maturity.     

Restricted thresholds for interval orders: A case of nonaxiomatizability by a universal sentence

Let $\text{P}$_n be the class of all finite interval orders that can be interval-represented using no more than n interval lengths or threshold levels. Thus $\text{P}$₁ is the class of finite semiorders, and $\text{P}$, the union of the $\text{P}$_n, is the class of finite interval orders. While each of $\text{P}$₁ and $\text{P}$ is axiomatizable by a universal sentence in first-order logic, no $\text{P}$_n for $\text{n ≧ 2}$ is axiomatizable in the same sense.     

Acquisition of representation-mediated conditioned food aversions

Food aversions were established in rats by administering lithium chloride (LiCl) immediately after the presentation of an exteroceptive conditioned stimulus (CS) which previously had been paired with a food substance. In Experiment 1, rats which received first tone-food and then tone-LiCl pairings showed less food consumption in subsequent testing than rats which received only tone-food or tone-LiCl pairings. Experiments 2 and 3 demonstrated the stimulus specificity of aversions established in this manner. Rats which first received pairings of light and tone CSs with two different food substances and then received pairings of one of those CSs with LiCl showed greater aversion to the food previously associated with the LiCl-paired CS than to the other food substance. Experiment 3 also showed that specific aversions were not acquired if rats received CS-shock rather than CS-LiCl pairings. These results suggest that CS-evoked representations of events can substitute for those events themselves in the formation of new associations.     

Imagery and verbal encoding in left and right hemisphere damaged patients

Neuropsychological aspects of imaginal and verbal encoding in memory were explored in two forced-choice recognition memory experiments with patients suffering from left and right anterior cerebral hemisphere damage. In the first experiment stimulus type and rate of presentation were varied. Predictions of patient performance based on the hypothesis that left anterior hemisphere pathology impairs verbal memory coding and right anterior hemisphere pathology impairs imaginal coding were confirmed. In a second recognition memory experiment for pictures of common objects, system-specific (imaginal or verbal) interference and distractor effects were demonstrated by analyzing the effects of interpolated tasks and the nature of false-recognition errors.