Recognizing faces in and out of context

Two experiments are reported which examined the influence of context on face recognition accuracy for novel and familiar faces respectively. Context was manipulated by varying the physical background against which the faces appeared. In Experiment I, 80 student subjects observed 18 faces before attempting to recognize them in a sequence of 36 al ternatives , For half the subj ects, the backgrounds changed from study to test, while for the remainder they stayed the same. In addition, for half the subjects, both the pose and expression of the face also changed, while for the others it remained constant. Changes in pose plus expression and context significantly reduced recognition accuracy for the target faces. Experiment 11 used an identical design, except that the faces of celebrities replaced the novel faces. The influence of context was eliminated but the effects of pose and expression were maintained. However, when only faces which were actually identified by subjects were considered, the effects of pose and expression, too, were eliminated. The significance of these findings for theories of contextual memory are discussed.     

Application of digital filters in the processing of eye movement data

Digital filter techniques have been applied to the analysis of eye movement data. Methods were developed to calculate eye velocity and eye acceleration in real-time from an electronystag-mogram (ENG) signal that was recorded using a one-pole RC high-pass filter in the preamplifier. Nonrecursive, finite impulse-response digital filters were designed to remove the effects of the RC high-pass filter and calculate the first and second time derivatives of the ENG signal, as well as remove high-frequency noise. Applying these new techniques to the analysis of vestibular nystagmus enables estimation of the transfer characteristics of the vestibuloocular system.     

Eye movement Responses of Repressors and Sensitizers to a stressful film

Groups scoring high, intermediate or low on the Byrne R-S Scale viewed an industrial accident film while horizontal eye movements were assessed by means of infrared corneal reflection. Neutral and stressful film segments were scored in terms of deviations from the center of the perceptual field (point of looking scores), and the standard deviations of these scores were calculated as an index of perceptual scanning. A stressful segment was also dichotically scored as to whether the point of looking was on or off dominant elements of the scene. Results indicated that Repressors and Sensitizers had equivalent levels of perceptual scanning (and both significantly higher than Intermediates' level) independent of film segment content, but that they differed in on/off and average point of looking for the stressful segment such that Repressors were avoiding stressful content. These data suggest that relatively high perceptual scanning can be an avoidant defensive style of attending to dynamic stimulus displays. The issue of adaptiveness of responding is considered.     

Short-term memory for spatial and temporal information

Two experiments examined the probed recall of visually presented letter sequences in which the items appeared at different spatial locations. Three types of probe were compared: (1) spatial position; (2) temporal association; and (3) combined position and association. In the first experiment, in which the spatial locations of the items were correlated with their temporal order, spatial probes were more effective than temporal association probes. In the second experiment spatial location was uncorrelated with temporal order, and spatial probes were less effective than temporal association probes. Regardless of the probe, errors tended to be items presented close in time to correct responses: spatial proximity was far less important. The results are discussed in terms of a storage system in which items and their spatial locations are organized within a temporal format. Both experiments showed superior combined probe performance, demonstrating that short-term retrieval is not limited to the use of one type of cue at a time. Secondary aspects of the results showed additionally that subjects can “edit” their responses to avoid making obvious mistakes, and that spatial location can be partially forgotten rather than being completely lost.     

Tactile vibration: Change of exponent with frequency

When cross-modality matches were made between a 60-Hz vibration and such other continua as electric current through the finger, number, force of handgrip, and both binaural and monaural loudness, the exponent of the power function for vibration was found to be about 1.0 at 60 Hz. The dependence of the exponent on frequency has been studied in a series of intramodality matching experiments. The exponent appears to reach its largest value in the vicinity of 30 Hz and its lowest value in the vicinity of 250 Hz. The highest value is roughly twice the lowest value. Over the low-frequency range, there is a suggestive similarity between the power functions for vibration and those for auditory loudness. As a vibration sensor, the ear may behave much like the finger.     

Cross-modality matching of brightness to loudness by 5-year-olds

The purpose was to determine whether 5-year-old children could match the brightness of a light to the loudness of a sound, and whether the resulting cross-modality function resembled the power function produced by adults. Each of five children adjusted the voltage on a 15D-W lamp to make the apparent brightness appear equal to the loudness of a 500-Hz tone, which the E set to eight different levels. The results resembled those of five adults who performed the same task.     

Are two heads better than one? Experimental investigations of the social facilitation of memory

The hypothesis that two people collaborating in recall would remember more than a single person was examined in a series of four experiments. All the experiments used variations on the same ‘sequential’ design where, in social conditions, people recalled alone initially and then recalled jointly in pairs: as a control for reminiscence, some people recalled alone on two separate occasions. On the second recall in all of the experiments two people always recalled more than one, but this was simply due to the independent statistical summation of two people's memories: no evidence whatsoever was found for the pairs of people generating new information that was not available to either member of the pair. This surprising result was not attributable to artefacts linked to the complexity or familiarity of stimulus material, nor was it linked to variations in people's cognitive perspectives. No evidence of social facilitation of memories was therefore found: two people recalling together certainly pool their separate memories so as to outperform individuals but the social interaction does not appear to generate previously unavailable memories.     

Yu and your mind

This note is a brief reply to the main argument of Qiuen Yu: 1992, Consistency, Mechanicalness, and the Logic of the Mind,Synthese 90, 145–79.