Seth Kunen

Spatial frequency content of visual imagery

Three experiments employing the McCollough paradigm were conducted to determine the spatial-frequency content of visual imagery. In Experiment 1, large and reliable pattern-contingent color aftereffects were obtained after adaptation to visual imagery. The direction of the aftereffects indicated that subjects were adapting to higher spatial frequencies in their imagery. These results contrast with the data of Experiment 2, which demonstrate that color aftereffects obtained with adaptation to physically present stimuli are mediated by the fundamental spatial frequency components. The magnitude of the imagery-induced aftereffects in Experiment 1 equaled the magnitude of the externally induced aftereffects obtained in Experiment 2 with the same subjects. By blurring the to-be-imaged patterns (Experiment 3), the fundamental Fourier components became the salient perceptual features of the stimuli, and the direction of the imagery-induced aftereffects was reversed from that of Experiment 1, indicating that the spatial frequency content of the imagery had changed from higher to lower frequencies. Under normal viewing conditions, subjects use the higher spatial frequencies associated with the perceptually salient edges of stimuli to construct their images. The results of Experiments 1 and 3 are discussed in light of a current controversy over the nature of information representation in imagery, and it is concluded that support has been obtained for the analog model of visual imagery.

Interocular transfer of orientation-contingent color aftereffects with external and internal adaptation

The issue of whether McCollough effects transfer interocularly was examined in two experiments. In Experiment 1, as in previous experiments, no interocular transfer of McCollough effects was obtained when subjects adapted monocularly to externally present patterns with their unused eyes fully occluded. However, when subjects adapted monocularly (with the unused eye fully occluded) to visual images of those patterns superimposed on physically present chromatic backgrounds, McCollough effects transferred interocularly. In Experiment 2, subjects adapted to either physically present patterns or to images of those patterns (as in Experiment 1), but the unused eye was exposed to unpatterned diffuse white light. In contrast to Experiment 1, the externally adapted subjects showed interocular transfer of McCollough effects. In Experiment 2, the magnitude of the interocular transfer effects produced by imagery was significantly larger than the magnitude of the effects produced by external adaptation, but the magnitude of the imagery-induced aftereffects did not differ from Experiment 1 to Experiment 2. These results extend earlier findings by Kunen and May (1980) and show that McCollough effects can be produced through adaptation to imagery, even though the direction of the imagery-induced aftereffects indicates adaptation to higher spatial frequencies whereas externally derived aftereffects indicate adaptation to lower spatial frequencies. It is concluded that failure of previous studies to obtain interocular transfer of McCollough effects may have resulted from complete occlusion of the contralateral eye. These data point up some interesting similarities and some important differences between imagery and actual vision. The implications for analogical models of visual imagery are discussed.

Do Verbal Descriptions Facilitate Visual Inferences

AbstractFourth and eighth graders, and college students were shown 60 pictures each depicting a simple action. Half the subjects at each grade gave a short verbal description of each picture and half simply visually inspected each picture. One week later the subjects were tested in a recognition task that included original study pictures plus new distractors. The verbal descriptions generally had the same effects at each age. Verbal descriptions increased both correct recognitions of study slides and correct rejections of unrelated distractors, while also increasing false recognitions of related distractors. The present results suggest that verbal labeling is a simple pedagogical technique that teachers can employ to significantly enhance children’s awareness of the meaning that underlies visual events.

Imagery-induced McCollough effects: Real or Imagined?

Recently, this journal published two studies, one by Broerse and Crassini (1980) and one by us (Kunen & May, 1980), that report contradictory findings on whether visual imagery can be used to induce contingent color aftereffects (CABs). We found, using a color-cancellation procedure, that CAEs could be produced from adaptation to visual imagery. These findings replicate and extend earlier findings of imagery-induced CABs reported by Finke and Schmidt (1977, 1978). In contrast, Broerse and Crassini (1980), using a forced-choice verbal report paradigm, report that no CABs could be obtained from adaptation to visual imagery and that interocular transfer of CAEs did not occur. 1 Finke (1981), in commenting on these articles, suggests that the failure of Broerse and Crassini to find CABs after adaptation to visual imagery might have reflected their use of a forced-choice method of measuring CABs. We also suspect that their failure to find imagery-induced CABs might have resulted from the particular method they employed. Broerse and Crassini told subjects that subsequent to adaptation they would view a test slide and would have to judge whether the test slide contained color and, if color was present, to rate the degree to which the color was present. Such a procedure may have enabled subjects to easily perceive a relationship between the study and test phases and to try to secondguess the experimenters. For example, after imagining patterns, the subjects may have figured out that there was no objectively present color in the test slides and may have felt that they were being tested for the extent to which they could be coaxed into believing that colors were present. In our colorcancellation procedure, it was virtually impossible for naive subjects to guess what our experimental hypotheses were or to see any relationship between the color-cancellation adjustments and the patterns in their imagery. Also, the color-cancellation procedure may measure CAEs more directly than verbal reports and thus may be a more sensitivemethod, The results of our study indicated that visual imagery can be a source of visual stimulation that induces CABs. Furthermore, the direction of the CAEs derived from imagery was opposite to the direction of CABs resulting from adaptation to well-focused externallypresent stimuli. Sinceit is well established that, with adaptation to checkerboard patterns of 3.0 c/d, CABs are derived from adaptation to the funda-

A Discriminant Function Analysis of Type A Behavior Using the 16PF Personality Questionnaire

The purpose of this study was to investigate the relationship of personality factors as measured by the 16PF Personality Questionnaire to Type A behavior as measured by the Student Form of the Jenkins Activity Survey (SJAS). One hundred and fourteen under-graduates were administered the SJAS and the 16PF Personality Questionnaire. Correlational and discriminant analyses revealed several systematic relationships between specific personality factors and Type A Behavior. The correlational analyses revealed nine significant correlations, while the discriminant analysis revealed six factors that discriminated between Type A and Type B personalities. The most important of these were the factors Venturesome, Suspicious, and Conscientious. These results indicate that the 16PF is a useful personality inventory that can discriminate Type A from Type B personalities as measured by the SJAS.

OLDER ADULTS’ JUDGMENTS OF HISTORICALLY IMPORTANT EVENTS: THE ROLES OF GENDER, AGE, AND EDUCATION

Middle‐aged and elderly individuals were asked to list the 10 most important events that have happened in the United States since 1900. The answers were classified into categories and analyzed as a function of gender, age, and education. We obtained mixed support for the notion that gender and age are related in systematic ways to value judgments. The results for the education variable, which was often involved in interactions with age, were considerably more complex. The effects of education were often the opposite on the middle‐aged and elderly. The findings were discussed in the context of Gilligans theory of gender differences in values, Eriksons (1950) and Gutmanns (1964) theories of age‐related changes in values, and Blooms (1987) educational theory of values. The results show that value judgments often vary in a complex fashion with variables such as age and education, making simple characterizations of the relationship between value judgments and such variables difficult.

Figural factors and the development of pictorial inferences

The role of figural characteristics in the development of pictorial inferences was examined. Two versions of 10 three-picture story sequences were presented to kindergarten and third-grade children. One version maximized while the other minimized figural similarity among pictures. After viewing the sequences, the children were asked to discriminate old study pictures and inferentially consistent new pictures from distractors. While the kindergarteners identified significantly fewer inference pictures than the third graders in all conditions, there was less difference between the grades in the figurally similar conditions. Overall, the kindergarteners identified the fewest inference pictures in the presence of distractors that figurally matched the study pictures. These results indicate that although the pictorial inferences drawn by kindergarteners are heavily influenced by figural representations, such figural dependency cannot account for all of the observed developmental differences.

Age-related differences in the magnitude of pattern-contingent color aftereffects

Pattern contingent color aftereffects were measured using a color cancellation technique in 6-, 8-, 10-, and 20-year-old subjects. Postadaptation test conditions involved immediate testing or testing after subjects were blindfolded for 60 min between adaptation and posttests. The 6- and 8-year-old subjects exhibited color aftereffects whose magnitude was significantly greater than those observed in 10- and 20-year-olds. In addition, aftereffect magnitude was significantlygreater after 60 min in the dark than when subjects were tested immediately. These findings are discussed in terms of their implications for the development of perceptual learning.