Pupillary response as a general measure of activation

Pupil size was measured while 30 male college students undertook five tasks respectively concerning, (a) muscle tension induced by the lifting of weights, (b) fear induced by threat of a gunshot, (c) intense stimulation induced by loud pure tones, (d) heightened attention from viewing novel pictures, and (e) pleasantness and unpleasantness in reaction to pictures that differed in terms of their affect-inducing characteristics. Highly regular relationships were found between pupil size and degree of muscle strain and between pupil size and the temporal ordering of events during threat of a gunshot. Significant effects on pupil size also were found for the other three types of stimulation.     

Defineability as an index of word meaning

A sample of 277 nouns was scaled for rated defineability and rated pronunciability. Intercorrelations were computed among the following variables: defineability (D), pronunciability (P), imagery (I), concreteness (C), associative meaningfulness (m), familiarity (F), and Thorndike-Lorge frequencies (TLF). RatedD was substantially related to all the other variables, notably to ratedI. Correlations were highest amongD, I, C, andm, on the one hand, and amongF, TLF, andP, on the other. The pattern of correlations was interpreted in terms of Paivio's (1970) distinction between higher-order and lower-order meaning. Two experiments were conducted to test the relationship between the word attributes and recall of word labels with dictionary definitions provided as retrieval cues. The positive effect ofD on label retrieval was independent of theI values of the defined words but the effectiveness ofI on retrieval was dependent on word defineability.This research was supported in part by grants to Dr. A. Paivio from the National Research Council of Canada (Grant 0087).     

Competing tasks as an index of intelligence

Most studies involving competing (or dual) tasks have been concerned with the investigation of models of attention and have stressed the importance of task characteristics in determining competing-task performance. The relatively few studies which have looked at individual differences in competing-task performance suggest that measures of this performance could reflect operations which are central to cognitive functioning. This paper examines two key questions which stem from this research: is there a separate ability involved in competing-task performance? Is competing-task performance more indicative of general intellectual functioning?A battery composed of both single and competing tasks was presented to 91 Ss. Two sets of scores, ‘primary’ and ‘secondary’, were obtained from the competing tasks. The results indicate that ‘single’ and ‘primary’ scores are basically measuring the same thing but that ‘secondary’ scores measure what is perhaps a time-sharing factor. There is also some evidence that primary and secondary scores are more indicative of the general factor, as measured by this battery, than their single counterparts.     

Matching as an index of face familiarity

An experiment is reported which explores a method of assessing familiarity that does not rely on the overt recognition or identification of faces. Earlier findings (Clutterbuck & Johnston, 2002; Young, Hay, McWeeny, Flude, & Ellis, 1985) have shown that familiar faces can be matched faster on their internal features than unfamiliar faces. This study examines whether familiarization in the form of repeated exposure to novel faces over a 2 day period can facilitate internal feature match performance. Participants viewed each of a set of unfamiliar faces for 1 min in total. At test on the second day previously familiar (famous) faces were matched faster than unfamiliar and familiarized faces. However the familiarized faces were matched faster than the unfamiliar faces. We discuss the use of this task as a means of accessing a measure of familiarity formation and as a means of tracking how faces become familiar.     

Self-generated cognitive fluency as an alternative route to preference formation

People tend to prefer fluently processed over harder to process information. In this study we examine two issues concerning fluency and preference. First, previous research has pre-selected fluent and non-fluent materials. We did not take this approach yet show that the fluency of individuals’ idiosyncratic on-line interactions with a given stimulus can influence preference formation. Second, while processing fluency influences preference, the opposite also may be true: preferred stimuli could be processed more fluently than non-preferred. Participants performed a visual search task either before or after indicating their preferred images from an array of either paintings by Kandinsky or decorated coffee mugs. Preferred stimuli were associated with fluent processing, reflected in facilitated search times. Critically, this was only the case for participants who gave their preferences after completing the visual search task, not for those stating preferences prior to the visual search task. Our results suggest that the spontaneous and idiosyncratic experience of processing fluency plays a role in forming preference judgments and conversely that our first impressions of preference do not drive response fluency.     

Finger-length as an index of assertiveness in women

A gene causing the index finger to be shorter than the ring finger is said to be dominant in men but recessive in women, with the result that more women have longer forefingers than men. Since this finger-length ratio varies considerably within sex, the possibility that it might relate to masculinity-femininity of social behaviour in women was investigated. Nine hundred and eighty-five women provided self-reports on the length of their fingers and their degree of assertiveness, without knowledge of the hypothesized link. Women whose forefinger was shorter than their ring finger were more likely to describe themselves as ‘assertive and competitive’ than women whose forefinger was longer than their ring finger. This finding could reflect the simultaneous effect of prenatal sex hormones on body and brain.     

Extension of the taste-test analogue as an unobtrusive measure of preference for alcohol

The utility of the taste-test analogue for obtaining an unobtrusive measure of preference for alcohol was examined. Thirty-two male undergraduates participated in each of two taste-rating tasks. In each task. subjects were presented with two beakers containing beverages they were to rate. Although one container was labeled “Alcohol”, and the other was labeled “Orange Juice”, both actually contained only orange juice. Subjects rated the beverages differently on 52% of the dimensions for which ratings were completed. Furthermore, subjects estimated that they had consumed an average of over three ounces of alcohol in the combined taste tests. Wider use of the analogue preference test may have significant value in the study of the determinants of human alcohol drinking behavior.     

Blinks as an index of cognitive activity during reading

Horizontal and vertical EOG recordings of eye movements were analyzed to determine the spatial and temporal distribution of blinks and the patterns of eye movements (saccades and fixation pauses) exhibited by six subjects during the reading of stories presented in two formats (on paper and on a VDT). The frequency and placement of blinks was not affected by the presentation condition. Blinks were determined to be non-randomly distributed during reading. Significantly more blinks (36%) occurred in conjunction with saccades than the proportion of time consumed by saccades (12%) would predict. Significantly more blinks (36%) occurred in the vicinity of line change saccades, which accounts for 15% of reading time, and with fixation pauses associated with regressions (42%), which accounts for 26% of reading time, than with fixation pauses during normal reading (22%), which accounts for 60% of reading time. The results of the study suggest that blink behavior during reading is under perceptual and cognitive control.     

Pupillary dilation as a measure of attention: a quantitative system analysis

It has long been known that the pupil dilates as a consequence of attentional effort. But the function that relates attentional input to pupillary output has never been the subject of quantitative analysis. We present a system analysis of the pupillary response to attentional input. Attentional input is modeled as a string ofattentional pulses. We show that the system is linear; the effects of input pulses on the pupillary response are additive. The impulse response has essentially a gamma distribution with two free parameters. These parameters are estimated; they are fairly constant over tasks and subjects. The paper presents a method of estimating the string of attentional input pulses, given some average pupillary output. The method involves the technique of deconvolution; it can be implemented with a public-domain software package, Pupil.