Looking time: The effects of stimulus complexity and familiarity

During a 10 min. stimulus familiarization period, three groups of 60 Ss each received either 0, 10, or 20 sec. of familiarization on each of 30 experimental stimuli: 10 each of low, medium, and high stimulus complexity. All Ss then viewed the experimental stimuli in a second task, during which they could look at each stimulus for as long as they wished (free looking). For half the Ss in each group, free looking was administered immediately after the familiarization period. The remaining Ss received free looking 48 hr. later. The results replicated earlier research which has shown that free looking time is inversely related to stimulus familiarity, and directly related to stimulus complexity. Unlike earlier findings, the data suggested that with a 48 hr. delay between familiarization and free looking, a stimulus can, at least partially, recover from the decrement in looking time produced by 10 sec. of familiarization.     

Attention,extraversion, and stimulus-personality congruence

In this study Ss classified as extraverts, ambiverts or introverts on the Maudsley Personality Inventory looked at photographs rated as extravert, ambivert, or introvert for as long as they wished. It was hypothesized that there would be a tendency for Ss to look relatively longer at pictures congruent with their personality characteristic. Support for this hypothesis was found in a significant picture by personality interaction. Extraverts clearly looked longer at extravert pictures and introverts showed a very slight preference for introvert pictures. Ambivert pictures were looked at the longest by all groups. This high looking time for ambivert pictures and the small difference between the looking time at extravert and introvert pictures by introvert Ss is explained in terms of greater complexity of the ambivert and extravert pictures used in this experiment.     

Stimulus complexity,free looking time,and inspective exploration

Fourteen Ss rated 59 objects on a seven point complexity scale. From these ratings 10 objects were chosen at the high, middle, and low levels of complexity, and 35 mm slides were made of these 30 objects. Fifteen Ss manipulated and inspected each of the objects for as long as they wished and a second group of 15 Ss viewed slides of the objects for as long as they wished. Analysis of the time scores from these two groups revealed that both inspective manipulation time and free looking time increased as a function of stimulus complexity. Inspective manipulation time was greater than free looking time except at the low complexity level.     

Attention,extraversion, and stimulus—personality congruence

In this study Ss classified as extraverts, ambiverts or introverts on the Maudsley Personality Inventory looked at photographs rated as extravert, ambivert, or introvert for as long as they wished. It was hypothesized that there would be a tendency for Ss to look relatively longer at pictures congruent with their personality characteristic. Support for this hypothesis was found in a significant picture by personality interaction. Extraverts clearly looked longer at extravert pictures and introverts showed a very s light preference for introvert pictures. Ambivert pictures were looked at the longest by all groups. This high looking time for ambivert pictures and the small difference between the looking time at extravert and introvert pictures by introvert Ss is explained in terms of greater complexity of the ambivert and extravert pictures used in this experiment.     

Stimulus familiarity,dogmatism, and the duration of attention

Thirtyeight males and 30 females viewed each of 30 black and white photographs for as long as they wished. Half the photographs were judged by the Es to be unfamiliar to college students. The remaining photographs were judged to be familiar. After the looking task all Ss cotnpleted the Dogmatism Scale. It was predicted that the open-minded Ss would spend more time looking at the novel stimuli than the closed-minded Ss, and, that all Ss would spend more time looking at novel stimuli than familiar stimuli. The results failed to confirm the hypothesis that open-minded Ss would look longer at the novel stimuli than closed-minded Ss. However, it was found that Ss spent more time looking at novel stimuli than familiar stimuli regardless of the degree to which their belief systems were opened or closed. The adwwtage of manipulating stimulus familiarity by E-selection of the stimuli was discussed.     

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.     

Reliability of looking time

Twenty-eight college students viewed two sets of 30 color photographs each under instructions to look at each picture for as long as they wished. Equal thirds of the stimuli in each set were selected from high, middle, and low complexity levels. The sets were presented 7–10 weeks apart. The results indicated significant between- and within-session correlations that were not dependent on stimulus complexity. It was suggested that the findings were indicative of a consistency in either the rate at which Ss process information or the amount of information they process or both.     

The influence of stimulus uncertainty and experimental instructions on visual selection

The looking behavior of adults and children was recorded while they viewed pairs of stimuli differing in stimulus uncertainty. Ss in one experimental group were encouraged to identify the stimuli and indicate whether they had been seen in a previous phase of the experiment. For the remaining Ss, instructions minimized the importance of the stimuli to the experiment. Results indicate that, when stimulus uncertainty was influential, the relationship between stimulus uncertainty and looking time was monotonically increasing. However, stimulus uncertainty was an effective determinant of looking behavior only when Ss were motivated to identify the stimuli. The behavior of adults and children did not differ.     

Implications of measurement of eye fixations for a psychophysics of form perception

It was suggested that insights into feature analysis of processes involved in form identification might be gained from an analysis of eye movements made by Ss as they identified patterns. Fixations were measured during identifications of histoforms, polygons, and Vargus 10 figures. Eye fixations were measured, and Ss rated sections of the figures in terms of their importance. Eye fixations were measured in terms of number of changes and duration of fixations. The number of changes in fixation were found to reflect only individual differences. Duration of fixation was found to vary significantly with location within figures, with fixations being longest where changes of contour occurred. There was also a tendency to look longer at the top of polygons and Vargus 10 figures and at the center of histoforms. Ratings of importance were highest for sections of figures fixated for longer duration-generally areas in which changes of contour were present.     

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.     

Effects of information conflict and complexity in visual figures on voluntary visual exploration, using structural information theory

This study was designed to examine the effects of information conflict and complexity on voluntary visual exploration quantitatively. 31 adults viewed each of 16 slides of geometrical figures and places for as long as they wished. The stimuli had two values of information conflict and complexity which had been calculated by means of structural information theory. Free looking times indicated that only when information conflict was low, voluntary visual exploration was positively correlated with complexity. Furthermore, voluntary visual exploration correlated positively with information conflict when complexity was low.     

Suggesting strategies improves creative visual synthesis

An experiment assessed whether a figural or an interpretative strategy can enhance creative visual synthesis. 45 undergraduates were presented a set of simple figures and asked to imagine combining them to obtain a whole pattern corresponding to a creative product. In the figurative condition participants were instructed to combine figures in unusual ways; in the interpretative condition they were induced to look for unusual meanings embedded in the combinations; in the control condition no strategy was suggested. Results showed that certain strategies induced a more flexible visual synthesis.     

Cross-modal transfer of forms between vision and touch

Cross-modal transfer (CMT) of figures was studied by varying stimulus complexity and age (9, 11, 14 years). Matched groups learned two series of 10 figures each (simple familiar and complex meaningless), one group first visually and then factually (V-T) and the other in reversed order (T-V), scanning time being unlimited. After learning the figures the Ss drew them from memory. These reproductions were mostly whole figures. CMT was significant in both directions. In the simple figure series transfer was regarded as symmetric, whereas the results for the complex figures suggested that the T-V order was more efficient. Transfer did not increase with age, but each age group had features typical of it.     

Sex differences in the duration of visual attention

Normal adult males and females looked at a series of photographs containing either a single adult male or female. Ss viewed each picture for as long as they wished. Assuming that measures of the duration of attention would reflect Ss attraction for the opposite sex, it was hypothesized that Ss would spend relatively more time viewing photographs of the opposite sex. The results failed to support the hypothesis. Although males did not differentially attend to the stimuli, females looked significantly longer at the females than they did at the males. The results were interpreted in terms of the “overt sexual content” of the stimuli and socially conditioned attentiveness and inattentiveness.     

Sex differences in the duration of visual attention

Normal adult males and females looked at a series of photographs containing either a single adult male or female. Ss viewed each picture for as long as they wished. Assuming that measures of the duration of attention would reflect Ss attraction for the opposite sex, it was hypothesized that Ss would spend relatively more time viewing photographs of the opposite sex. The results failed to support the hypothesis. Although males did not differentially attend to the stimuli, females looked significantly longer at the females than they did at the males. The results were interpreted in terms of the “overt sexual content” of the stimuli and socially conditioned attentiveness and inattentiveness.     

Complexity-simplicity,symmetry-asymmetry,and sociometric choice

In order to study the interrelationships associated with shape preference, 30 undergraduate Ss made complexity-simplicity and symmetry-asymmetry choices, and also made sociometric choices of others as well as predicting the sociometric choices of others. Ss who preferred complexity tended to choose Ss who preferred symmetry, which was interpreted as complementary choice. Other findings suggest that complexity and asymmetry are not identical, although there is some relationship between the two.     

The latency of response in relation to Bloch’s law at threshold’

Bloch’s law failed to hold for latencies of response in a threshold experiment where frequencies ofresponse did, nevertheless, obey the law. Dark-adapted Ss were instructed to respond as soon as they detected flashes of various luminances and durations. The frequency of response increased with increases in stimulus energy (luminance times duration); it was constant when energy was constant. The latency of response, measured from stimulus onset. varied inversely with energy; it also varied inversely with the luminance of flashes that were constant in energy. The results were consistent with data from earlier threshold and simple reaction time experiments.     

Cultural Differences in Visual Search for Geometric Figures

While some studies suggest cultural differences in visual processing, others do not, possibly because the complexity of their tasks draws upon high‐level factors that could obscure such effects. To control for this, we examined cultural differences in visual search for geometric figures, a relatively simple task for which the underlying mechanisms are reasonably well known. We replicated earlier results showing that North Americans had a reliable search asymmetry for line length: Search for long among short lines was faster than vice versa. In contrast, Japanese participants showed no asymmetry. This difference did not appear to be affected by stimulus density. Other kinds of stimuli resulted in other patterns of asymmetry differences, suggesting that these are not due to factors such as analytic/holistic processing but are based instead on the target‐detection process. In particular, our results indicate that at least some cultural differences reflect different ways of processing early‐level features, possibly in response to environmental factors.     

Ear asymmetry in a dichotic detection task

Pairs of consonant-vowel (CV) syllables were presented dichotically to Ss who were instructed to monitor for the presence of a target CV which could occur in either ear. Ss responded by depressing a response button ; reaction time (RT) was also recorded. Right ear targets were detected 6.2% more frequently, on the average, than left ear targets and had an average RT 50 msec quicker than their left ear counterparts. These results demonstrate the existence of a right ear superiority in dichotic listening when a nonverbal motor response measure is used, supporting the contention that the ear asymmetry phenomenon is truly perceptual in nature and not merely due to the lateralization of verbal output. Two alternative explanations of the RT difference between left and right ear targets are offered. One attributes this difference to the time necessary for intercortical transfer of right hemisphere information, while the second holds that it is due to the longer times needed by the right hemisphere to process information projected to it.     

Consistency between motor activity and perceived direction of rotation

Three experiments were conducted to test the proposition that engagement in motor activity in a given direction favors the perception of stimulus movement consistent with that direction. Ss simultaneously turned a crank and viewed a stimulus capable of apparent reversal of direction.Experiments 1A and 1B demonstrated that the perceived initial direction of rotation was more stable when it was consistent with the motor activity of the viewer than when it was inconsistent. Experiment 2 demonstrated that when Ss were instructed to perceive a particular direction of rotation for a period of time they tended to engage in motor activity consistent withthatdirection.The results were interpreted as supporting an efference theory of perception.