A new approach to the generation of visual stimuli for eye-movement research

An interactive, computer-controlled, visual stimulus generator is described, suitable for both psychophysical and neurophysiological experimentation on human subjects. The system core is a wide-screen electrostatic cathode-ray tube, which can be used both as a television monitor, to display standard video pictures, and as anx-y oscilloscope, so that a bright dot can be moved around the display by electrical signals. In addition, a third working mode is provided, according to which a time-compressed video picture of limited size (fast picture) plays the role that is typical of the spot in a standard oscilloscope. Through computer-assisted time compression, the frame period of the video signal is reduced to about one tenth of its standard value. The fast picture can accordingly be driven by even the fastest eye movements, and it can be displayed as a stabilized image, or, more generally, in the altered retinal feedback condition. Moreover, as compared with a standard video picture, the fast image can be “flashed” over much shorter time periods. Since a standard input video signal is used for both standard and fast video pictures, all the image processing facilities of commercial videographic systems can be fully exploited by the proposed device.     

Mental image reversal and verbal recoding: When ducks become rabbits

A recent debate has concerned whether classical bistable configurations (e.g., duck/rabbit) can be reinterpreted using mental imagery. Research in this field indicates that image reversal is possible only when subjects change their specification of orientation. In a series of four experiments, we demonstrate that mental reversal of classical bistable configurations( CBCs) is impeded by verbally recoding the visual pattern at the time of input. When subjects were prevented from verbally recoding visual stimuli in short-term memory, they fared systematically better in mentally reversing the CBC, even when they received no instructions to change their reference frame or specification of orientation. On this basis, we suggest a model of image reversal that takes into account the interaction between memory codes and provides a new perspective on verbal recoding, verbal overshadowing, and mental discoveries.     

Disordered eating in women of color

It has been assumed that the occurrence of eating disorders in American racial minority groups are rare. Indeed, whereas the cultural context may afford “protection” to the group, it does not necessarily protect specific individuals. Individuals within each racial/ethnic group are subject to the standards of the dominant culture, particularly when the culture-of-origin is devalued by the dominant culture. Social, familial, and individual factors which contribute to disorders eating symptomatology are discussed. Discussions of obstacles to detecting eating disorders and guidelines for developing more inclusive theory of and treatment of persons with eating disorders is included.     

Positive Psychological States in the Daily Life of a Sample of Working Women

This study of a sample of working women investigated where positive experiences were derived from in everyday life, focusing on the domains of work and nonwork (leisure). It examined how aspects of the situation, in terms of principal environmental influences in work and leisure, and the person, in terms of locus of control, were associated with positive subjective states and psychological well-being. The study employed questionnaires and also the experience sampling method. The results showed that both work and leisure were important for positive psychological states and that internal locus of control was associated with greater enjoyment, interest, feelings of immediate control, intrinsic motivation, life satisfaction, and affective well-being and a number of principal environmental influences.     

The logics of orthoalgebras

The notion of unsharp orthoalgebra is introduced and it is proved that the category of unsharp orthoalgebras is isomorphic to the category of D-posets. A completeness theorem for some partial logics based on unsharp orthoalgebras, orthoalgebras and orthomodular posets is proved.     

The recollective experience of cross-modality confusion errors

There are at least two qualitatively different types of subjective experience that can accompany accurate recognition memory. Sometimes recognition is accompanied by conscious recollection of the learning episode (i.e., it isremembered), and in other cases it is not (i.e., it is simplyknown that the item is old). In the present study, we assessed the subjective experience that accompanies crossmodality confusion errors (misidentifying words as pictures) by measuring the extent to which subjects claimed toremember versusknow that the item was presented as a picture. The results of two experiments demonstrate that cross-modality confusion errors are often accompanied by conscious recollection, although not to the same extent as accurate memories. The findings also show that there is considerable overlap in the recollective experience that accompanies accurate and erroneous memories. Finally, the results support the contention that recollective experience cannot be directly inferred from test performance.     

Auditory temporal perception deficits in the reading-impaired: A critical review of the evidence

We assess evidence and arguments brought forward by Tallal (e.g., 1980) and by the target paper (Farmer & Klein, 1995) for a general deficit in auditory temporal perception as the source of phonological deficits in impaired readers. We argue that (1) errors in temporal order judgment of both syllables and tones reflect difficulty in identifying similar (and so readily confusable) stimuli rapidly, not in judging their temporal order; (2) difficulty in identifying similar syllables or tones rapidly stem from independent deficits in speech and nonspeech discriminative capacity, not from a general deficit in rate of auditory perception; and (3) the results of dichotic experiments and studies of aphasics purporting to demonstrate left-hemisphere specialization for nonspeech auditory temporal perception are inconclusive. The paper supports its arguments with data from a recent control study. We conclude that, on the available evidence, the phonological deficit of impaired readers cannot be traced to any co-occurring nonspeech deficits so far observed and is phonetic in origin, but that its full nature, origin, and extent remain to be determined.     

My place,your place,and no place: Behavior settings as a risk factor for HIV-related injection practices of drug users in Baltimore,Maryland

Information is sparse on the social context of illicit drug injection behaviors and their relationship to HIV infection. This study examined relationships between injection settings, injecting with others, and HIV risk behaviors of sharing needles and not cleaning contaminated needles in a sample of 630 inner-city injecting drug users in Baltimore, MD. Through open-ended interviews, five primary settings of injection behavior were identified. These settings included one's own, friends' and mother's residence, shooting galleries, and semipublic areas. Most participants reported injecting in their own residence (92%) and friends' residence (86%) in the prior 6 months. In a multiple regression analysis, injecting at friends' residence, in shooting galleries, and in semipublic areas and frequency of injecting with others were significantly associated with frequency of sharing uncleaned needles, “slipping” (i.e., failure to disinfect shared needles), and not always cleaning used needles before injecting. Results suggest that interventions may benefit from targeting settings as well as behaviors to reduce the spread of HIV. This research was supported by grants DA04334, DA05911, DA06313, and DA08985 from the National Institute on Drug Abuse.     

Memory impairment and source misattribution in postevent misinformation experiments with short retention intervals

The four experiments reported here provide evidence that (1) misleading postevent suggestions can impair memory for details in a witnessed event and (2) subjects sometimes remember sug-gested details as things seen in the event itself. All four experiments used recall tests in which subjects were warned of the possibility that the postevent information included misleading sug-gestions and were instructed to report both what they witnessed in the event and what was men-tioned in the postevent narrative. Recall of event details was poorer on misled items than on control items, and subjects sometimes misidentified the sources of their recollections. Our re-sults suggest that these findings are not due to guessing or response biases, but rather reflect genuine memory impairment and source monitoring confusions.     

The effect of cue-familiarity, cue-distinctiveness, and retention interval on prospective remembering

Five experiments investigated the effects of cue familiarity, cue distinctiveness, and retention interval on prospective remembering. Results showed that (1) performance in a prospective memory task is facilitated when the cue is unfamiliar and/or distinctive; and (2) it is impaired by 3-minutes' delay between the instructions and the task (Experiment 1). A beneficial effect of distinctiveness was also found when perceptual rather than semantic distinctiveness was tested (Experiment 2). Experiments 3 and 4 ruled out the hypotheses that “unfulfilled expectancy” of an event (i.e. non-appearance of the cue during training) (Experiment 3), or some sort of “habituation” in the target context (Experiment 4), may have caused the low performance observed in the delayed conditions. Finally, results from Experiment 5 showed that delay negatively affected prospective remembering when it was filled with either a demanding interpolated activity (practice in a STM task) or an undemanding motoric activity (repetitive hands movements). Unfilled delay and an undemanding verbal activity (counting) were found not to affect prospective memory. Implications for the mechanisms underlying prospective remembering are discussed.