Necessity, possibility and belief: A study of syllogistic reasoning

The present study extended the investigation of the belief bias effect in syllogistic reasoning in two ways: (1) The effect was studied under instructions to decide whether conclusions were possible, as well as necessary, given the premises; and (2) the effect was studied for types of syllogism where people rarely endorse the conclusions as well as those (valid and fallacious) where endorsements are common. Three experiments are reported, which show first that there is a marked tendency to reject unbelievable conclusions relative to abstract or neutral controls on all kinds of syllogism and under both types of instruction. There was also significant evidence of positive belief bias (increased acceptance of believable conclusions) and of interactions between belief bias effects and logical form. The results are discussed with particular respect to accounts of belief bias offered by theorists in the mental-model tradition.     

Effect of context on perception of emotion among psychiatric patients

The purpose of this research was to examine the extent to which verbal statements of context influence psychiatric patients' perception of photographs of emotion (fear, anger, sadness, and happiness). The major findings showed that, when photographs were paired congruently with context statements, there were significant changes in agreement among subjects on two of the four emotion stimuli. There was significantly less agreement on the meaning of facial expressions when the stimuli for fear, anger, and happiness were accompanied by incongruent verbal statements than when they were viewed alone. These data appear to have implications for practitioners working with this population.     

Automatic detection vs controlled search: a paper-and-pencil approach

A new measure of selective attention was presented to 259 normal volunteers. The test was derived from earlier work which emphasized the importance of controlling the distracting conditions using a selective-attention paradigm. In the present study a paper-and-pencil, digit-cancellation format was introduced and the data documented a significant dissociation between tasks analogous to controlled search and automatic detection, two theoretically important aspects of selective attention. Presented is a discussion of similarities and differences of the new measure and classical methods of discriminating between controlled search and automatic detection and the potential significance of this discrimination in clinical neuropsychological investigations.     

Perceptual processing of adjacent and nonadjacent tactile nontargets.

Previous research has shown that subjects appear unable to restrict processing to a single finger and ignore a stimulus presented to an adjacent finger. Furthermore, the evidence suggests that, at least for moving stimuli, an adjacent nontarget is fully processed to the level of incipient response activation. The present study replicated and expanded upon these original findings. The results of Experiment 1 showed that an equally large response-competition effect occurred when the nontarget was presented to adjacent and nonadjacent fingers (on the same hand). The results of Experiment 2 showed that the effects observed in Experiment 1 (and in previous studies) were also obtained with stationary stimuli. Although small, there was some indication in the results of Experiment 2 that interference may dissipate more rapidly with distance with stationary stimuli. An additional finding was that interference effects were observed in both experiments with temporal separations between the target and nontarget of up to 100 msec. In Experiment 3, target and nontarget stimuli were presented to opposite hands. Although reduced, interference was still evident with target and nontarget stimuli presented to opposite hands. Varying the physical distance between hands did not produce any change in the amount of interference. The results suggest that the focus of attention on the skin extends nearly undiminished across the fingers of one hand and is not dependent upon the physical distance between sites of stimulation.     

Perceptual processing of adjacent and nonadjacent tactile nontargets

Previous research has shown that subjects appear unable to restrict processing to a single finger and ignore a stimulus presented to an adjacent finger. Furthermore, the evidence suggests that, at least for moving stimuli, an adjacent nontarget is fully processed to the level of incipient response activation. The present study replicated and expanded upon these original findings. The results of Experiment 1 showed that an equally large response-competition effect occurred when the nontarget was presented to adjacent and nonadjacent fingers4on the same hand). The results of Experiment 2 showed that the effects observed in Experiment 1 (and in previous studies) were also obtained with stationary stimuli. Although small, there was some indication in the results of Experiment 2 that interference may dissipate more rapidly with distance with stationary stimuli. An additional finding was that interference effects were observed in both experiments with temporal separations between the target and nontarget of up to 100 msec. In Experiment 3, target and nontarget stimuli were presented to opposite hands. Although reduced, interference was still evident with target and nontarget stimuli presented to opposite hands. Varying the physical distance between hands did not produce any change in the amount of interference. The results suggest that the focus of attention on the skin extends nearly undiminished across the fingers of one hand and is not dependent upon the physical distance between sites of stimulation.