Asymmetric attributions for compliance: Reward vs punishment

It was proposed that people attribute an individual's behavior more to internal factors when that individual's actions are influenced by reward than when those actions are influenced by punishment. Previous research has failed to control for the power of reward versus punishment which, in effect, creates a confounding of behavioral base rates (consensus) with the reward-punishment manipulation. The current research created reward and punishment contingencies that were equal in their base rates for producing a compliant response. In Experiment 1, subjects (n = 63) who produced the base-rate data also made attributions regarding a compliant target person. The results supported the reward-punishment attributional asymmetry hypothesis in that the target person was held more responsible for his actions in the reward than in the punishment conditions. A second experiment (n = 72) provided some attributors with information regarding base rates for compliance and measured perceived base rates for compliance. Knowledge of the base rates for compliance eliminated the reward-punishment attributional asymmetry phenomenon. Subjects not provided with such knowledge erroneously assumed different base rates for reward and punishment and maintained the perception of reward-punishment attributional asymmetry. Using subjects' estimates of base rate for compliance as a covariate eliminated the attributional asymmetry effect. It is suggested that erroneous base-rate assumptions mediate the attributional asymmetry phenomenon.     

Delayed alternation in the rat: Effect of contextual stimuli on proactive interference

The effect of contextual stimuli on proactive interference in the rat was investigated in three experiments. The task was a modified delayed alternation procedure in which the rat was initially forced to one side of a T maze (the interfering forcing) followed by a forcing to the opposite side (the target forcing). A free choice run followed the target forcing in which a turn in either direction could be made. In order to obtain reinforcement on the free choice run, the rat was required to turn in the direction opposite that of the target forcing (i.e., in the same direction as the interfering forcing). Manipulation of the context prevailing during the interfering forcing, target forcing, and free choice runs revealed that free choice accuracy was (a) greater when the interfering and target forcings were conducted in different contexts than when they were conducted in the same context and (b) influenced only slightly, if at all, by whether the free choice context coincided with that prevailing during the interfering forcing or with that prevailing during the target forcing.     

Verbal and nonverbal recognition memory in aphasic and nonaphasic stroke patients

The ability to retain lists of verbal and nonverbalizable items across recurrent recognition tasks was tested in three groups: (1) stroke patients with a left-brain lesion and aphasia, (2) stroke patients with a right-brain lesion and left hemiplegia, and (3) nonneurologically impaired outpatients. As determined with signal detection measures, aphasics were deficient in discriminating words that were to be remembered from those that were not; their recognition of nonverbal visual (geometric art) or auditory (bird calls) patterns, however, was unimpaired. Left hemiplegics showed the opposite pattern. After a long-term interval (<10 min), correct recognition of words was diminished in all groups whereas recognition of visual patterns increased. Both groups of stroke patients adopted material-specific decision criteria which in part accounted for the dissociation of verbal and nonverbal recognition memory by laterality of lesion. Item analysis indicated that aphasics' verbal memory difficulties were affected by acoustic-semantic confusion of list words.     

Cortical stimulation and speech timing: A preliminary observation

Audio recordings of the speech of seven patients receiving cortical stimulation during epilepsy surgery were acoustically analyzed, and duration measurements of the sound /s/ under stimulation and nonstimulation conditions were compared. It was found that in the dominant hemisphere, stimulation tended to significantly increase the duration of /s/; but not all stimulation sites were comparably affected. Stimulation of frontal lobe locations was also observed to more frequently result in durational increases than when temporal or parietal sites were stimulated. However, for sites affected, the actual magnitude of durational increase was comparable among the three lobes.     

Eye movements and performance during bilateral tracing tasks

To examine the role of current visual monitoring in the between-hand differences in skilled movements, eye movements and errors during bilateral tracing tasks were analyzed in 10 subjects. When subjects traced a horizontal course abductively with both hands, the subject's gaze followed the movement of the right hand, and more errors were observed on the left hand. When subjects traced a vertical course, where fine motor control for alteration of movement direction was necessary, more errors were shown on the left hand despite the alternate visual scan of the two hands. The results were interpreted as showing that the between-hand differences in skilled movements are primarily due to the left hand's poor ability in motor output, and that the differential efficiency in the use of visual monitoring becomes an important factor in the between-hand differences when symmetrical movements of both hands with a low degree of difficulty are required.     

An olfactory investigation of the compatibility of oddity instructions with the design of a 3-AFC signal detection task

There are two principal differences between the Triangular Method and the 3-Alternative Forced-Choice (3-AFC) procedure originating from the theory of signal detection. These are the instructions given and the types of three-stimulus sets (‘triangles’) presented to the subject.In the Triangular Method the subjects are instructed to select the odd stimulus from each triangle presented, whilst in the 3-AFC task the subject must either select the strongest or identify the weakest stimulus.The triangles presented in the Triangular Method sometimes contain two physically weak stimuli plus one stronger, and at other times two strong stimuli plus one weaker. In contrast, in a 3-AFC experiment all the triangles comprise either two weak plus one stronger, or two strong plus one weaker stimulus.Previous research has shown that the parameter d' is invariant with the two procedures, if the appropriate models are used for conversion of proportions of correct responses into corresponding values of d'.The present experiments provide evidence that the Triangular Method instructions (to select the odd stimulus) used in combination with the 3-AFC task design (using three types of triangles) does not result in biased estimates of d'. In addition, it was shown that even after a large number of presentations the value of d' remained stable, which supports the notion of stability of the decision rule implied by the oddity instructions.     

The dilution effect: Nondiagnostic information weakens the implications of diagnostic information

In a series of studies, subjects were asked to make predictions about target individuals. Some subjects were given information about the target which pretest subjects had judged to be “diagnostic”—that is, had judged to be usefully predictive of the outcome. Other subjects were given a mix of information judged to be diagnostic and information judged to be “nondiagnostic” by pretest subjects—that is, judged to be of little value for predicting the outcome. Subjects given mixed information made much less extreme predictions than did subjects given only diagnostic information. It was argued that this “dilution effect” occurs because people make predictions by making simple similarity judgments. That is, they compare the information they have about the target with their conception of outcome categories. The presence of individuating but nondiagnostic information about the target reduces the similarity between the target and those outcomes that are suggested by the diagnostic information. One of the major implications is that stereotypes and other “social knowledge structures” may be applied primarily to abstract, undifferentiated individuals and groups and may be largely set aside when judgments are made about concrete, individuated people.     

On the problems of being more or less the same

Sixty children aged 2–3 to 5-2 were given four quantity tasks which tested their understanding of more and same. Two tasks involved addition, two involved judgment of static quantities. One of each type of task required a manipulative response, and one of each required a yes/no judgment. The tasks involved judgments of equality and inequality. Tasks involving a manipulative response were significantly easier than those involving a yes/no judgment, indicating that the nature of the response required of the child is crucial. All other differences were negligible, indicating that the other task variables investigated do not affect the child's ability to respond correctly. The ability to make accurate responses was not strongly associated with counting ability. There was a significant difference in the children's counting responses depending on the method used to elicit it.