Movement and illumination factors in adaptation to prismatic viewing

While wearing laterally displacing prisms, Ss were required to align a spot of light to the phenomenal straightahead. These measurements were obtained at the beginning and at the end of an exposure to prismatic displacement. In addition, Ss either actively controlled movement of the spot of light, or movement was manipulated by E under the direction of the S. Aftereffects were determined by having S position the spot of light with normal vision at the beginning of the experiment and after each measurement obtained under prism viewing. Ss in the darkened room condition who were required to align the spot of light actively showed a significant aftereffect in the direction of prismatic displacement both at the beginning and at the end of the exposure period. No difference in the degree of adaptation was found between those measurements at the beginning and at the end of the exposure period. No significant aftereffects were found when the room was illuminated during prism exposure or when E controlled movement of the light source.     

A comparison of auditory monitoring performance in blind subjects with that of sighted subjects in light and dark

Two experiments were performed in which blind Ss, sighted Ss working in the dark, and sighted Ss working in the light were compared as to their efficiency on an auditory watchkeeping task. Absolute and differential auditory thresholds were measured in both experiments, and in the second experiment the groups also underwent a signal detection session under alerted conditions. There was some inconsistency as to relative performance of the sighted groups, but in both experiments the blind Ss were superior on the auditory watchkeeping task as to signals detected and effective sensitivity (d’). 1 This difference was not attributable to a difference in auditory sensitivity or to a criterion adopted for     

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.     

On the perception of a class of bilaterally symmetric forms

Two experiments were performed to determine the manner in which people perceive a class of bilaterally symmetric forms. In the first experiment, paired, comparison dissimilarity judgments and unidimensional single stimulus ratings were collected from the Ss. The second experiment involved the collecting of semantic differential and paired comparison dissimilarity judgments from two groups of Ss. The judgments and ratings from both experiments were compared to each other and to a set of objective measures of the forms by a series of multivariate statistical techniques. It was found that three primary attributes, orientation, convexity-concavity, and curvature, accounted for the perceptual reports, but the manner in which the attributes were used differed for different response procedures and for the same response on different occasions.     

Nonvisual judgment of the crossability of path gaps.

The ability of persons to locomote without vision with the aid of a hand-held probe was investigated in 4 experiments focusing on the negotiation of gaps in a pathway. In Experiment 1, Ss of extreme heights judged under sighted and blindfolded conditions whether gaps of different sizes could be crossed by walking. Crossability boundaries were lower for shorter Ss, but the height effect disappeared under normalization by leg length. Experiments 2-4 altered mechanical aspects of the probe (length and mass distribution) in the nonvisual case. Ss' performance was still reliable in each experiment, and their performances were constrained by parameters of the gap and of their action systems. Probe variables, however, had surprisingly little influence on the judgments of crossability. Results were discussed in terms of potential roles for information in different perceptual modalities.     

Response requirements and the contrast effect in loudness judgments

Ss responded to a series of soft tones via category judgments, reaction time responses, or simple nonquantitative discrimination judgments. An evaluation was then made of the contrast effects obtained in the category judgments of these same soft tones when subsequently presented along with a series of loud tones. A control group was also used which did not receive the initial trials with the soft tones. The results indicated: (1) equivalent contrast effects for all four groups for the soft tones and (2) significantly greater judgments of the loud tones in the group that had used category judgments on the initial trials with soft tones. These results, alonR with a trend analysis, were used to argue for a joint semantic shift and equalization of category usage process underlying the contrast effect when Ss are required to denote the stimuli initially by means of category judgments.     

Effects of discriminability and irrelevant information on absolute judgments’

The effects of irrelevant information (0, 1, 2, or 3 bits stimulus) on absolute judgments of size were measured at different levels of discrimination difficulty. The stimuli were 7 small circular spots of light of different sizes, selected from an eaual-discriminability scole, and arranged into 6 pairs that represented different levels of stimulus dissimilarity. Three of the pairs comprised a low-dissimilarity (LD) subgrouping in which different lepels of dissimilarity and discriminability were confounded, whereas the remaining three pairs comprised a high-dissimilarity (HD) subgrouping in which different levels of dissimilarity occurred at a single high level of discriminability. Different colors were used to provide the four levels of irrelevant information; 240 Ss (10 in each of the 24 experimental conditions) made absolute judgments of size under the classical procedure for the method of single stimuli. Separate analyses of errors, reaction times, and rates of information transmission indicated that irrelevant information had an increasingly detrimental effect on absolute judgments as discrimination difficulty was increased (in the LD subgroup), but essentially no effect where discriminations were easily modefin the HD subgroup).     

Neutral vs ego-orienting instructions: Effects on judgments of magnitude estimation

Three experiments were performed to examine the relative constancy of the exponent in the psychophysical power law under varying motivating conditions. The method of magnitude estimation was used to obtain judgments of apparent tactual roughness or of apparent area size of squares. Patterns of the qualitative observations of the three Es and of the various exponents for the six groups of Ss indicated that neutral instructions and “ego-orienting” instructions, which were perceived as unbelievable coming from an equal fellow student, both yielded exponents identical to those reported in the literature. Believable ego-orienting instructions given by an E of clearly perceived higher social status produced a statistically significantly lower exponent than neutral. Intermediate conditions, wherein Ss apparently disbelieved both types of instructions, but assumed that the superior-status E was “analyzing” them, yielded exponents of intermediate size. Results and supplementary trend analyses are discussed as possible, highly sensitive indicators of motivational impacts on sensory judgments.     

Size constancy in extended haptic space

When a stick is used to extend the boundaries of the world perceived by touch, haptic parallels to visual angle and size constancy appear. In a pilot study, Ss using a stick to feel an out-of-reach gap were more likely to underestimate its size than were Ss feeling a nearby gap with the index finger, but size constancy was relatively high with the stick. The main study, comparing judgments of gaps at intermediate and far positions, confirmed these findings. Errors were greater for the more distant gap, but constancy was high in both positions. Correlations between far and intermediate judgments indicated that Ss were consistent in the type of error made. Similar findings emerged from a partial replication with blind and partially sighted Ss.     

Dark adaptation and the Hermann grid illusion

The latency of the perception of the dark spot at the intersection of a Hermann grid was measured before and after dark adaptation. It was found that dark adaptation significantly increased the latency of perception of the spot while light adaptation had no effect. This finding was predicted from the Jung and Spillman account of the Hermann grid illusion and from the Kuffler et al. finding that inhibitory receptive fields of the cat’s retinal ganglion ceils are reduced in size and responsiveness after dark adaptation. The significance of this finding in relation to other simultaneous contrast phenomena is discussed.     

Structural alignment in similarity and difference judgments

Similarity is a central construct in models of cognitive processing, and as such has been the focus of psychological inquiry. This work has revealed that similarity and difference judgments are not always inverses. One explanation for this effect is that similarity judgments focus on matching relations between the items, while difference judgments focus on the mismatching attributes. A second explanation is that both similarity and difference judgments involve a process of structural alignment, and that they use the output of this process differently. These views are contrasted by using the one-shot mapping technique that places attribute similarity and relational similarity in competition. The results suggest that similarity and difference judgments both involve structural alignment.     

The role of gradients of binocular disparity in Gibson’s theory of space perception

Adult Ss made distance bisection judgments over a surface on which the packing density of the texture elements was progressively increased along the Ss’ line of sight from one end of the surface to the other. Distance judgments were significantly different under monocular and binocular conditions of vision; however, with binocular vision, Ss did not detect the deformation in the texture on the surface. This result does not support predictions derived from Gibson, Purdy, and Lawrence (1955) concerning the role of gradients of binocular disparity in Gibson’s psychophysical theory of space perception.     

Color preferences, extraversion, and neuroticism of art students.

Color preferences of 190 art students (G?tz & G?tz, 1974, 1975) were compared with the corresponding scores on extraversion (E) and neuroticism (N). It was found that the preferences of a group of 27 highly gifted young artists were different from preferences of average and less gifted Ss who had little or no artistic practice. In the latter group extraverts and ambiverts mainly preferred primary and secondary colors (light clear and dark clear tones included), while introverts preferred tertiary colors (earth colors) and achromatics. However, in the group of highly gifted Ss no significant differences between positive and negative rankings in both color categories were found. Neuroticism had no effect on color preferences; this holds for introverts and extraverts and for each single color.     

Unwanted thought: age differences in the correction of social judgements

This study use a false information paradigm to study age differences in the correction of social judgments. Younger and older adults read 2 criminal reports, with true information printed in black and false information in red. Following the reports, all participants were asked to recommend prison terms among other ratings. Age differences in baseline measures were also assessed by corresponding control groups who read only true information. Compared with younger adults under full attention, older adults under full attention and younger adults under divided attention were reliably influenced by the nature of the false statements (either extenuating or exacerbating the severity of the crimes). When contrasted with their relevant control groups, older adults under full attention and younger adults under divided attention failed to correct their social judgments. This study lends support to a processing resource explanation for age differences in the correction process for social judgments.     

Visual orientation during and after lateral head,body, and trunk tilt

Visual judgments of orientation were investigated during (effect) and after (aftereffect) different body postures. In Experiment 1 four trained Ss made apparent verticality (AV) judgments before and after 2 min in each of seven orientations: head tilt left and right, body tilt left and right, trunk tilt left and right and a control condition with head ’and body upright. The aftereffect was significant for all postures excepting trunk tilt left and the control. The aftereffect from head tilt was greater than that from the same degree of body tilt, and that in the trunk tilt condition was in the same direction as’ predicted from neck stimulation. In Experiment 2, 30 Ss made AV judgments during tilt in the same seven postures. The E-phenomenon resulted from both head and body tilts, and an effect was found for trunk tilt in the direction predicted from neck stimulation. The results are discussed in terms of the otolith, neck, and trunk receptor systems.     

Contributions of specific cell information to judgments of interevent contingency

College students considered the possible effect of an experimental drug on a skin rash. The information came from a 2 x 2 contingency table involving receipt or nonreceipt of the drug and improvement or nonimprovement of the rash: Cell A = receipt-improvement; Cell B = receipt-nonimprovement; Cell C = nonreceipt-improvement; Cell D = nonreceipt-nonimprovement. Without numerical information. Ss judged cells to be ordered A greater than B greater than C greater than D. The same order held when the contribution of each cell was derived from the contingency judgments of other subjects given numerical information. No such consistency was seen when one group of Ss made both judgments: whether individual Ss equally or unequally assessed the importance of the four cells, their contingency estimates showed cell use to be ordered A greater than B greater than C greater than D. These findings may result from strong biases that Ss harbor in processing contingency information.     

Tests of product and additive scaling axioms

A product axiom for ratio judgments and an additive axiom for difference judgments were tested for six Ss judging brightness. The product axiom was rejected for all six Ss whereas the additive axiom was accepted for two Ss. Power functions did not fit the data well, although somewhat better for difference judgments than ratio judgments. A two-stage model fitted somewhat better, but failed to satisfy one important implication of that model, previously confirmed for lifted weights. The data gave stronger support for a theory of brightness estimation based on an additive axiom for difference judgments than a product axiom based on ratio judgments.     

Blacky the Cat,I: Semantic Differential Ratings

Two criteria for an alternate form of the Blacky Test, designed to facilitate female identification with Blacky are suggested: 1) the main character must be perceived by females as more feminine than the original stimulus, and 2) the main character must not be viewed differently by male and female Ss in other respects. Semantic Differential ratings of both the original Blacky stimuli and a revised “sexually neutral” cat form (N = 320) indicated that an alternate version could meet both these requirements. Differences between the responses of female Ss to both forms were further shown to be a) generally specific to female Ss, b) specific to the character of Blacky (rather than Mama) and c) often enhanced when Ss made judgments after having seen all twelve cartoons of the test, rather than only the first two.     

An individual differences analysis of interdimensional additivity in multidimensional scaling

Comparative judgments of the dissimilarity between schematic faces varying on 1, 4, 7, or 10 binary attributes were obtained under two instructional sets. Using the Tucker-Messick procedure, three subgroups of like-perceiving Ss were isolated and the nature of cue-utilization by each described. Perceptual independence of attributes was demonstrated both within and between instructional sets for Subgroups 1 and within instructional sets for Subgroup 2. The Subgroup 3 results indicated an interaction of the attributes. Data from the Shot cognitive elements test differentially characterized Subgroups 1 and 2, but did not uniquely characterize Ss requiring more complex models for the combination of attributes. The study illustrates the possible usefulness of an individual differences approach to the study of selective attention and information processing.     

Mood effects on attitude judgments: independent effects of mood before and after message elaboration.

This study investigated the independent effects of induced mood on the encoding of persuasive messages and on the assessment of attitude judgments. In Experiment 1, positive or negative mood was induced either before the encoding of a counterattitudinal message or before the assessment of attitude judgments. When mood was induced before message presentation, Ss in a bad mood were more persuaded by strong than by weak arguments, whereas Ss in a good mood were equally persuaded by strong and by weak arguments. When Ss encoded the message in a neutral mood, however, the advantage of strong over weak arguments was more pronounced when Ss were in a good rather than in a bad mood at the time of attitude assessment. In Experiment 2, Ss exposed to a counterattitudinal message composed of either strong or weak arguments formed either a global evaluation or a detailed representation of the message. Positive, negative, or neutral mood was then induced. Ss in a good mood were most likely and Ss in a negative mood least likely to base their reported attitudes on global evaluations.