The effect of companion on consumption of ethanol solution in cats

Social influences on drinking ethanol solution were studied in two cats (“drinkers”) who voluntarily drank small amounts of 10% ethanol solution in milk and three other cats (“nondrinkers”) who served as companions to the drinkers. A 15-minute sesion was conducted daily in a compartment divided into two even parts with a transparent Plexiglass partition. The cats were introduced to the compartment either singly or in pairs. Each pair consisted either of two drinkers or one drinker and one nondrinker. Each cat of the pair was placed in one part of the compartment; the cats could see each other, but they could not make physical contact. Each drinker was offered 10% ethanol solution in milk, while each nondrinker was given plain milk, and the amount of consumption was measured. A series of five to ten sessions with a drinker was followed by a series of sessions with a nondrinker or with no companion. There were a total of 13 series of sessions for each drinker. A statistical analysis of the data showed that, in most series, the mean amount of consumption of ethanol solution was significantly higher in the presence of a companion (either drinker or nondrinker) than in its absence.     

Dual coding under conditions of second stimulus modality uncertainty in successive matching tasks

Subjects matched successively presented stimuli within and across modalities. In conditions in which they were informed of the modalities of the two stimuli, no differences in matching performance were obtained between the four types of match (visual-visual, auditory-auditory, visual-auditory, and auditory-visual). Thus, there appeared to be no difference between the modalities in ability to perceive or retain the particular stimuli used. In conditions in which subjects were informed of the modality of the first stimulus but only of the modality in which the second stimulus would appear on 80% of trials, there was again no significant difference between auditory-auditory and visual-visual matching. However, auditory-visual matching was much faster than visual-auditory matching when the second stimulus appeared in the unexpected modality. The results suggest that subjects prepare for both possible types of match when uncertain of the second stimulus modality and that the cross-modal asymmetry reflects the additional attentional load that this incurs.     

Neuronal NT-3 Is not Required For Synaptic Transmission or Long-Term Potentiation in Area CA1 of the Adult Rat Hippocampus

Neurotrophic factors, including BDNF and NT-3, have been implicated in the regulation of synaptic transmission and plasticity. Previous attempts to analyze synaptic transmission and plasticity in mice lacking the NT-3 gene have been hampered by the early death of the NT-3 homozygous knockout animals. We have bypassed this problem by examining synaptic transmission in mice in which the NT-3 gene is deleted in neurons later in development, by crossing animals expressing the CRE recombinase driven by the synapsin I promoter to animals in which the NT-3 gene is floxed. We conducted blind field potential recordings at the Schaffer collateral–CA1 synapse in hippocampal slices from homozygous knockout and wild-type mice. We examined the following indices of synaptic transmission: (1) input-output relationship; (2) paired-pulse facilitation; (3) post-tetanic potentiation; and (4) long-term potentiation: induced by two different protocols: (a) two trains of 100-Hz stimulation and (b) theta burst stimulation. We found no difference between the knockout and wild-type mice in any of the above measurements. These results suggest that neuronal NT-3 does not play an essential role in normal synaptic transmission and some forms of plasticity in the mouse hippocampus.     

Stereospatial masking and aftereffect with normal and transformed random-dot patterns

Masking and aftereffect in the perception of binocular depth were studied using random-dot sterograms as adaptation and target stimuli. Detection of the target was impaired by prior adaptation only when the two stimuli differed in disparity by less than 2 minarc. The masking function was unaffected by uniocular enlargement and blurring within the adaptation stimulus, but masking was no longer selective to disparity when the elements seen by the two eyes were reversed in brightness. The stereoscopic depth aftereffect was also insensitive to uniocular enlargement and blurring, and could not be generated when there was brightness complementation within the adaptation stimulus. Both the masking and aftereffect data are interpreted as evidence that stereospatial detectors in human vision are insensitive to transforms that maintain luminance-spatial correlations in binocular input.     

Some generalization and follow-up measures on autistic children in behavior therapy

We have treated 20 autistic children with behavior therapy. At intake, most of the children were severely disturbed, having symptoms indicating an extremely poor prognosis. The children were treated in separate groups, and some were treated more than once, allowing for within- and between-subject replications of treatment effects. We have employed reliable measures of generalization across situations and behaviors as well as across time (follow-up). The findings can be summarized as follows: (1) Inappropriate behaviors (self-stimulation and echolalia) decreased during treatment, and appropriate behaviors (appropriate speech, appropriate play, and social non-verbal behaviors) increased. (2) Spontaneous social interactions and the spontaneous use of language occurred about eight months into treatment for some of the children. (3) IQs and social quotients reflected improvement during treatment. (4) There were no exceptions to the improvement, however, some of the children improved more than others. (5) Follow-up measures recorded 1 to 4 yr after treatment showed that large differences between groups of children depended upon the post-treatment environment (those groups whose parents were trained to carry out behavior therapy continued to improve, while children who were institutionalized regressed). (6) A brief reinstatement of behavior therapy could temporarily re-establish some of the original therapeutic gains made by the children who were subsequently institutionalized.     

Effect of task difficulty on the division of attention between nonverbal signals: Independence or interaction?

Models of divided attention are grouped into two classes according to whether they assume that efficiency on one task is independent of or interacts with the level of difficulty on a second simultaneously performed task. On the basis of contradictory evidence from previous studies, four necessary requirements are proposed for an empirical test between the two classes of model. Two experiments successfully embodying these requirements were run, in which subjects performed a two-choice recognition task, involving frequency and intensity signals presented together and alone. The independent variable was the level of difficulty on one dimension; the dependent variable was the accuracy of performance on a second dimension presented at the same time. The results from both experiments showed an interactive trend, performance becoming worse as the difficulty of the accompanying task was increased. In neither case was the effect significant. When pooled over experiments the effect appeared to be reliable, although small. The outcome is interpreted as supporting interactive models of divided attention rather than independent models. Possible reasons for the smallness of the effect are considered. The most likely reason appears to be the competing demands between two of the test requirements adopted initially. An alternative to one of the requirements is proposed.     

Division of attention between non-verbal signals: All-or-none or shared processing?

Criteria proposed by Broadbent (1971) for deciding between “all-or-none” and “shared” models of divided attention are reviewed and modified. Of the modified criteria, the amount of the reduction in efficiency and the shape of the normalized ROC curve are identified as being diagnostic for deciding between the two models. When applied to the results of two experiments involving the recognition of difficult nonverbal signals, which showed performance on the signals presented together to be significantly worse than performance on the signals when presented alone, both the criteria favour the shared model rather than the all-or-none model. The results of a third experiment with easy signals indicated that artefacts unrelated to attention were unable to account for the reduction in efficiency with difficult signals. It is concluded that the shared model, which assumes some limit to processing capacity, has the widest application to these results and similar findings reported elsewhere. The role of the all-or-none model would appear to be restricted to conditions of extreme informational overload. Further, the movement of noncentral decision criteria and the unequal contribution of the individual dimensions to overall multi-dimension performance demonstrated in the first two experiments, suggest that a reduction in the quality of decision-making may accompany the division of attention, as well as the reduction of information derived from the signals.     

Division of attention: Evidence for a between-trial component of impaired performance

Detection and recognition studies are reviewed, which show a dependency between errors on successive trials. They suggest the impairment accompanying the presentation of simultaneous signals may also involve a similar “between-trial” component. The hypothesis was tested using a two-choice recognition paradigm with bimodal signals. Dimensions presented simultaneously were interleaved on alternate trials with a single dimension presented alone. Interleaving two signals in the first experiment showed no effect on the following signal presented alone, compared to a control condition in which the signal always preceded itself. Interleaving four signals in the second experiment produced a significant impairment. Accounts of the results based on the length of the response interval, fluctuations of state variables such as arousal and decay of the memory trace are rejected. Accounts based on the impairment and set-size of preceding simultaneous signals are retained. Both suppose part of the impairment accompanying simultaneous signals to be a between-trial phenomenon. Implications of the results for work on divided-attention are considered and a method of experimental control proposed.     

Attitudes toward sex-roles: Traditional or egalitarian?

This article reports on the development of a Likert-type scale measuring attitudes toward egalitarian-traditional sex roles. A total of 484 undergraduates participated in six phases of the study. An item analysis study yielded 20 items with part-whole correlations <.48. The corrected split-half reliability coefficient is .91 (p.001). Five other phases of research show promising concurrent and construct validity. In particular, traditional attitudes are related to rigidity as measured by authoritarian, religious, same-sex touching, rape acceptance, divorce, and conservative attitudes. Overall, a varimax rotated factor analysis revealed one major factor accounting for 84.6% of the variance. Further, females were shown to have higher levels of egalitarian attitudes as compared to males.