Mobilization of Cognitive Resources and the Generation Effect

The generation effect refers to the memory advantage of words that have been generated rather than read. Such a read-generate comparison confounds qualitative task differences and raises methodological problems. A revised methodology is proposed circumventing these problems in that the encoding task is held constant and all stimuli have to be generated, but the degree of generativeness (i.e. the amount of cueing) is varied. In Experiment 1, 1, the (refined version of the) generation effect is demonstrated in a within-subjects design; with increasing generation activity left to the subject, free recall performance increases. No effect is obtained for degree of target masking. The same finding is replicated and shown to be independent of self-paced study time when generative activity is manipulated between subjects (Experiment 2) or within subjects (Experiment 3). As all learning trials involve generation, encoding time is controlled statistically, and free recall is used as a measure of memory, this refined generation effect cannot be explained as an artifact of selective attention or elaboration. Rather, generative activity seems to increase the mobilization of cognitive resources. This motivational account is supported by Experiment 4 showing an enhanced generation effect for positive mood.     

Many stimuli are frightening,but some are more frightening than others: The contributions of preparedness,dangerousness, and unpredictability to making a stimulus fearful

The nonrandom distribution of situational fears has been explained by evolutionary survival relevance of specific fears. Thirty-eight stimuli were taken from the literature on preparedness and were scored on fearfulness, objective dangerousness, and spatiotemporal unpredictability by three separate groups of students. The same items were scored on survival relevance by 15 biologists. Fearfulness of cues significantly correlated not only with survival relevance but also, and even more strongly, with dangerousness and unpredictability. While the fear/survival relevance association virtually disappeared when the unpredictability contribution was partialed out, the fear/unpredictability correlation was only marginally affected when controlling for survival relevance. This suggests that nonrandomness of feared stimuli may result from the spatiotemporal unpredictability that is attributed to these stimuli. The current practice of using snakes and spiders as phobia-relevant, and flowers and mushrooms as neutral, cues was not justified by the ratings of the 15 independent experts.This study was supported in part by a grant from the Dutch Organization for Fundamental Research (ZWO/Psychon, 560-268-001).     

Covariation detection in treated and untreated spider phobics.

Twenty treated and 18 untreated spider phobics were exposed to a series of 72 slides. Three different categories of slides were used: phobia-relevant slides (spiders), alternative fear-relevant slides (weapons), and neutral slides (flowers). Slides were randomly paired with either a shock, a tone, or nothing at all. Despite the absence of a systematic correlation between slides and outcomes, untreated phobics strongly overestimated the covariation between spider slides and shock. Treated phobics did not show a covariation bias, suggesting that such bias can be modulated by behavioral treatment. In addition, untreated subjects were more confident about their contingency estimates than were treated subjects. The present results fit with earlier studies.     

Effects of gaze manipulation on subjective evaluation of neutral and phobia-relevant stimuli. A comment on Drake's (1987) 'Effects of Gaze Manipulation on Aesthetic Judgments: Hemisphere Priming of Affect'

Using neutral stimuli (mushrooms and flowers) and phobia-relevant stimuli (snakes and spiders), the present investigation examined the effect of gaze shifts on subjective evaluation of stimuli in female subjects (N = 29). One group of subjects had to orient to the right, whereas the other group had to orient to the left in order to see the stimuli. When left-handed subjects were excluded from the analysis, the results showed that subjects in the 'orient right' group gave a significantly more positive evaluation than subjects in the 'orient left' group. The results provide a replication of the phenomenon described by Drake (1987).     

Restrained eaters are rapidly habituating sensation seekers

Several authors have pointed to similarities between eating disorders and addictive behaviors. In earlier studies, addicts were found to score high on the Sensation Seeking Scale (SSS) and to habituate rapidly to neutral stimuli. In this study, we found experimental support for an addiction model of eating disorders: restrained eaters also scored significantly higher on the Sensation Seeking Scale and also habituated significantly quicker to a series of neutral stimuli than unrestrained eaters. No clear evidence was found for the hypothesis that restrained eaters score lower on measurements of anxiety. It is hypothesized that rapid habituation promotes sensation seeking, which may be manifested in excessive consumption of either drugs or food. Restraint may be a strategy to prevent negative consequences of sensation seeking and excessive consumption. The model is related to earlier experimental findings.     

TIME RELATIONS IN DREAMS: A preliminary note

Examples are given of hypnotically induced dreams, which support the notion that series of experiences corresponding to long spans of objective time may be represented in dreams of very short duration. Both stimulus and organismic factors determine the contents of such dreams.     

Evidential support and undermining: Revision of Håkan Törnebohm's theory of confirmation

In 1975, An Essay on Knowledge Formation by H. Törnebohm was published in this Journal. Its content in revised form was included in a work in Swedish of 1983 on knowledge development.HT defines his confirmation criterion in terms of a measure oftruth degree T, which is based on a measure ofmatching M, which is also used as a measure of the degree to which propositionp (an hypothesis) is supported or undermined by another propositionq (the evidence forp),M is defined in terms of a measure of thecontent C.     

No attentional bias for pictoral stimuli in spider-fearful subjects

A number of experiments have shown that (spider) fearful subjects direct their attention to fear-relevant words, even when these words are irrelevant to the completion of a target task (e.g., color naming). The present study examined whether subjects with an intense fear of spiders also display such attentional bias for a fear-relevant pictoral stimulus. Female spider-fearful (n=13) and control subjects (n=13) saw neutral patterns (i.e., horizontal and vertical bars). One pattern served as target for a reaction time, while the other pattern served as nontarget. Targets and nontargets were accompanied by either fear-relevant or neutral pictoral material (i.e., a picture of a spider or a picture of a flower, respectively). The fear-relevant picture did not selectively delibate reaction time performance of spider-fearful subjects. Thus, no evidence was found for an attentional bias for fear-relevant pictoral material in subjects with an intense fear of spiders. Instead, fearful subjects exhibited a general inhibition of performance which became stronger over trials. This suggests that the fear-relevant picture induced a state of anxious arousal or defensive withdrawal that interfered with reaction time performance on both fear-relevant and neutral trials.     

Sensitivity of persons with hearing impairment to visual emotional expression — compensation or deficit?

The research examined whether subjects with hearing impairment would differ from normal hearing subjects in their ability to decode emotions from video stimuli (48 video takes in which two actors portrayed six different emotions). Studies in tactile and visual perception lead one to expect deficits, while there is also some evidence for compensation. Twenty-six subjects with hearing impairment and 26 matched normal hearing subjects participated (average age = 25.5 years; nine female, 17 male subjects in each group). Results indicate that in general subjects with hearing impairment were slightly less successful in decoding emotions from the visual stimuli than the normal hearing subjects. A comparison between highly (loss > 60–90 dBA) and moderately (loss about 30–60 dBA) impaired subjects on the other hand indicated poorer emotion decoding only for the moderately impaired group. Post-hoc analyses indicated that these effects were specific to males. Results are discussed with respect to compensation versus deficit, and with respect to issues of training.