Influence of exploration time on haptic and visual matching of complex shape

The time adult Ss were allowed to explore stimuli was varied during intra- and cross-model equivalence matching involving vision and touch. Increasing time to explore either each standard, each comparison, or both standard and comparison from 4 to 16 sec significantly improved haptic intramodel matching. However, cross-modal matching, from either vision to touch or touch to vision, improved significantly only when time to explore each standard was increased. Videotape recordings of Ss’ hand movements revealed use of a greater variety of haptic scanning strategies by Ss in groups where increased exploration time enhanced accuracy. The difference in effects of exploration time on intra- compared to cross-model shape matching was discussed in terms of possible differences in requirements between the two tasks.     

The kinesthetic spatial aftereffect as a function of the angular displacement of the joints of the arm

The magnitude of the kinesthetic spatial aftereffect following different angular displacements from the vertical and horizontal planes during stimulation was examined in two experiments using 278 Ss. Both Gibson’s direct and indirect effect were found when angular displacements were away from the vertical, however, a bimodal pattern was observed in both experiments when stimulation was away from the horizontal. An explanation for the interaxial difference cannot be provided by conventional theories and must be sought in a consideration of the structure of the joints which are involved with the production of the aftereffect.     

Presence of human friends and pet dogs as moderators of autonomic responses to stress in women

Autonomic responses were measured while 45 adult women performed a standard experimental stress task in the laboratory with only the experimenter present and 2 weeks later at home in the presence of a female friend, pet dog, or neither. Results demonstrated that autonomic reactivity was moderated by the presence of a companion, the nature of whom was critical to the size and direction of the effect. Ss in the friend condition exhibited higher physiological reactivity and poorer performance than subjects in the control and pet conditions. Ss in the pet condition showed less physiological reactivity during stressful tasks than Ss in the other conditions. The results are interpreted in terms of the degree to which friends and pets are perceived as evaluative during stressful task performance. Physiological reactivity was consistent across the laboratory and field settings.     

The effect of the repeated presentation of a standard interval on the reproduction of the standard

The Langley Porter Neuropsychiatrie Institute, San Francisco, California 94122 Eleven human Ss (five male and six female) reproduced intervals of 1, 2, and 3 sec delimited by clicks after the standard intervals had been repeated one, three, or five times. The absolute error of reproduction decreased with increasing repetition of the standard for intervals of 2 and 3 sec. The effect was more pronounced with increasing duration among female Ss.     

Parallel processing in item recognition

It is shown that in Sternberg’s item recognition task Ss need not make a judgment of the absolute size or color of the test item before comparing it with memory. However, Ss do use size or color information, when possible, to reduce long reaction times for large memory loads. The results suggest that Ss are able to scan memory for form in parallel with testing for gross stimulus features, like size or color. This finding has important implications for sequential two-stage theories of attention.     

The equivalence of target and nontarget processing in visual search

A comparison of a forced-choice visual search task with an item recognition task did not support Neisser’s (1967) hypothesis of a preattentive stage that processes targets and nontargets differentially. In the forced-choice condition, Ss indicated which of two items in a visual display was a target; in item recognition, Ss determined whether or not the single item in the visual display was a target. The size of the memorized set of possible targets was varied from one to six items for both tasks. Latencies increased linearly with memory set size in both conditions; the slopes for forced choice and item recognition were 41.8 and 27.9 msec per item, respectively. The ratio of 1.38 between the two slopes was well fit by Sternberg’s (1967) item recognition model, which predicts a ratio of 1.50.     

Human sensory dominance

Human Ss matched an auditory and a visual stimulus for subjective magnitude. Then each stimulus was used as a cue in a reaction time task. On occasions when both stimuli were presented simultaneously, Ss’ responding was seen to be dominated by the visual stimulus. Of further interest was the finding that on some occasions of simultaneous light-tone presentation Ss were unaware that the tone had been presented. This apparent prepotency of the visual over the auditory stimulus was seen to persist across a variety of experimental conditions, which included giving Ss verbal instructions to respond to the tone when both stimuli were presented simultaneously.     

The psychophysics of the kinesthetic aftereffect in the Petrie block experiment

Kinesthetic size is reported in the Petrie experiment by a simultaneous size comparison in which a standard block held between the thumb and forefinger of one hand is matched in size by moving the thumb and forefinger of the opposite hand along a wedge until the proper width is reached. After a baseline is obtained, a kinesthetic aftereffect is produced by rubbing a block of contrasting size followed by a return to the standard block. Experiments with 22 male Ss and 20 female Ss, tested in separate cycles, show that augmentation following stimulation with a block smaller than standard and reduction following stimulation with a block larger than standard are both statistically significant, and, at least for augmentation, the aftereffect persists for at least 48 h. When the data are corrected for regression there is no significant relationship between initial baseline and the amount of augmentation or reduction; reasons why such a relationship has been reported are indicated. The results suggest that when this kind of experiment is used for the study of individual differences (a) it is satisfactory to derive augmentation and reduction scores by subtracting the baseline from the absolute scores, provided the scores are corrected for regression, and (b) a counterbalanced order of presentation is not advisable in view of the carryover of augmentation from one day to the next, which is likely to make the two orders incommensurate.     

Distance discrimination and observer strategy in judgments of relative size

Six paid Ss participated in an experiment designed to assess the effects of observer strategy and the detectability of a distance cue on judgments of relative size. Ss viewed stimulus pairs through a 21-in. tunnel at one end of an 8-ft table. The Standard stimulus, 94 in. from S, was individually paired with three larger and two smaller comparison stimuli 96 in. from S. A slit of light on the table 95 in. from S and 90 deg to his line of sight served as distance cue. Increases in distance detection improved accuracy of relative size judgments when the comparison stimulus was larger than the Standard stimulus, but decreased accuracy when the comparison stimulus was smaller. Magnitude of this effect varied directly with Ss’ post-experimental reports of judgmental strategy. These findings confirm the importance of distance discrimination in judgments of actual size and the necessity to control perceiver characteristics in the study of size-distance relationships.     

Individual differences in power functions for a 1-week intersession interval

Two experiments examined correlations of the power function exponents of individual Ss obtained in each of two sessions. Half the Ss for any task performed second sessions immediately after the first, the other half after a week’s delay. In Experiment I, groups of 16 Ss gave magnitude estimations of apparent area, or else of area and loudness. In Experiment II, groups of 16 Ss made cross-modality matches of apparent time duration to area. Significant correlations in all cases indicated consistent and persisting S differences in exponents. The results are related to the findings of other studies of such individual differences.     

Effect of exteroceptive feedback in controlling electrodermal activity in pre-conditioned fears.

Ss with a strong fear of snakes were taught to increase and decrease their skin resistance during practice sessions with a continuous visual display. Ss were not aware that they were increasing or decreasing their levels of skin resistance and attempted only to influence the magnitude of the multimeter display, the polarity of which was controlled by the experimenter. The study used a within-subjects reversal design to investigate whether bidirectional control could be acquired over skin resistance level. To investigate whether this acquired control could affect the magnitude of elicited pre-conditioned autonomic responses, a pre- and post-training comparison was made between the GSRs elicited during test sessions in which Ss viewed slides of snakes while attempting to influence their electrodermal activity with the assistance of the visual display. The results suggest that Ss are able to acquire voluntarily bidirectional control of their level of skin resistance with continuous visual feedback and that this control can either depress or facilitate the magnitude of pre-conditioned emotional responses as a function of visual feedback.     

The effect of structure and degree of tilt on the tilted room illusion

The effect of structure and angle of tilt on the magnitude of the tilted-room illusion and its relationship to the illusion produced by a tilted-line field were examined in two experiments. In Experiment L, nine groups of 13 Ss were tested under three conditions of room tilt in the frontal plane (22.5, 45, and 67.5 deg) and under three conditions of structure (empty room, room with a back wall of stripes, and room with furniture). The results indicate that, while magnitude and direction of the illusion vary with degree of room tilt, structure increases the magnitude of the illusion only at a 45-deg room tilt. In Experiment 2, a field of lines was presented through a circular reduction tube to three groups of 13 Ss under three conditions of line tilt (22.5, 45, and 67.5 deg). An illusion occurred that was much smaller in magnitude and functionally different for the three tilt conditions when compared with the tilted-room illusion.     

Visual on- and off-latencies and handedness

Ten Ss served in this experiment, five right-handed and five left-handed. Every S was tested in a perceived-order situation and by the up-and-down method to determine the relative on-latency for a visual test stimulus. i.e, (ON-Lat for lest stimulus involving right hemisphere- ON-Lat for standard stimulus involving left hemisphere) and to determine a similarly defined relative off-latency for the same test stimulus. The algebraic difference between the relative on-latency measure and the relative off-latency measure was then found. Data from a previous study had suggested that this “on-off difference” was characteristically positive for left-handed Ss and negative for right-handed Ss. The present data agree. The left-handed Ss were found to differ significantly from the right-handed Ss in the magnitude of the on-off difference. This outcome appears important as a possible clue to functional interhemispheric differences related to handedness.     

Distance judgments under different size-information conditions

Seventy-two Ss judged the absolute distance of a target presented without distance cues other than retinal size and assumed size. The method by which E communicated information about the size of a 3-in. target had a significant effect on the magnitude of the discrepancy between judged distance and the perceived distance required by the size-distance invariance hypothesis. In order of increasing effectiveness in producing distance judgments meeting invariance requirements were: size information in the form of verbally communicated metric units, size information communicated by labeling the target with the name of a familiar object, and size information in the form of a visual representation.     

Judgment stability and pseudorecognition of random and patterned configurations

Thirty six simple patterns were judged as “random” or “patterned” by adult Ss. Category judgments were consistent whether Ss were told that 1/4, 1/2, or 3/4 of the patterns were random or if no proportion was specified. In a second experiment, Ss viewed a series of slides previously judged patterned followed by a recognition series with two additional patterned slides inserted in a series of otherwise random slides. Although slides were never labeled random or patterned, Ss made the most false recognitions for the two patterned slides. In another condition where random and patterned slides were reversed, most false recognitions were made for the two random slides. Both Gamer’s notion of hypothetical set size and an analysis of balanced elements fit the results, but the adequacy of both hypotheses can be questioned when applied to previous results with more complex patterns.     

Paired comparison scaling of reaction potential from simultaneous measurements of GSR and looking time

Thurstone’s method of scaling from paired comparison data was employed to obtain estimates of reaction potential on eight successive presentations of randomly generated polygons. One set of scale values was based upon the magnitude of the GSR made by each of 40 Ss to the onset of each stimulus. Another set of scale values was based upon the Ss looking times, when the S was instructed to press a switch to terminate the stimulus after he finished looking at it. Following termination of each stimulus, a 20-sec period of no stimulation intervened prior to the next stimulus. The GSR reduced in size from trial to trial, describing a typical habituation curve, while looking time increased from trial to trial. Across trials the two sets of scale values were significantly negatively correlated (r=?0.91). The failure to find habituation of looking time was explained on the assumption that the 20-sec period between stimuli was noxious to the Ss, which resulted in longer and longer looking times across trials. These results were interpreted as indicating that habituation of the GSR is not merely a matter of reduced attention in the cognitive sense. In addition, it was pointed out that the use of orienting reflex concepts in dealing with attentional and other cognitive phenomena may be unjustified.     

The effect of texture oil the magnitude of

The magnitude of simultaneous brightness contrast was measured while the coarseness of the textural overlay was varied. Remits from 10 Ss indicate that as the size of elements in the texture increases, the amount of obtained contrast decreases. An interpretation of these results in terms of the spread of lateral inhibitory effects is offered.     

Memory and the experience of duration in retrospect

Two experiments investigated the relationship between long-term memory for events occurring during an interval and the experience of duration of the interval in retrospect. In both, Ss attended to a sequence consisting of a standard, an experimental, and a second standard interval. Then unexpected comparative duration and memory judgments were requested. In Experiment I, either 30 or 60 unrelated words occurred during the 180-see experimental interval. When more words had occurred, judgments of duration of the experimental interval, judgments of number of words presented, and number of words recognized all increased, but free recall of words was unaffected. In Experiment II, 80 categorized words occurred during the 160-see experimental interval, with category instances in either blocked or random order. When words were blocked by category, judgments of duration of the experimental interval, free recall, and recognition all increased, but judgments of number of words were unaffected. Results were discussed in terms of Ornstein’s (1969) “storage size” hypothesis.     

The effects of instructions,fixed rate of presentation,and complexity on free looking time

The effect of stimulus complexity, prior experience with a short or long fixed rate of presentation (FRP) and S’s knowledge concerning the purpose ot the experiment on free looking time (FLT), was examined. Results indicated that under all conditions, Ss view complex stimuli longer than simple. A long FRP produced longer FLT than did a short FRP for Ss uninformed of the purpose of the experiment, hut FRP had no effect on FLT for Ss who were informed.     

THE PROPERTIES OF DISTRIBUTIONS OF MAGNITUDE ESTIMATES OF LOUDNESS AND SOFTNESS

JOHN, I. D. The properties of distributions of magnitude estimates of loudness and softness. Scand. J. Psychol. 1971, 12, 261–270.–Distributions of magnitude estimations (MEs) of loudness and softness made by ten Ss to ten repetitions of ten stimuli were examined. Skew and relative variability of the distributions of MEs of individuals Ss was inconsistent with hypotheses advanced by Stevens & Guirao (1962) and Eisler (1962). The results were interpreted as consisted with Eriksen & Hake's (1957) subjective standard hypothesis, and a tendency to use large numbers with relatively greater consistency than smaller numbers. A reciprocal relationship was not found between MEs of loudness and softness.