Internet use in the contemporary media environment

Although a significant amount of research has focused on traditional media choice and use, and even on some ‘new’ media, these studies have either neglected the Internet and World Wide Web or were conducted prior to their recent popularity. This study offers a novel exploration of individuals' use of three Internet functions (information retrieval, information giving, and conversation capabilities) in the context of the use of other communication media. Data from 684 individuals demonstrate that the Internet is a multidimensional technology used in a manner similar to other, more traditional media. Specifically, conversation features of the Internet align with mediated interpersonal technologies (the telephone and electronic mail), whereas the Internet's information‐retrieval and information‐giving features are used in ways similar to mass media channels (newspapers, television, and books and magazines). In addition, needs fulfilled by these channels cluster in ways consistent with past research, regardless of the technologies employed to meet them.     

A generalized visual latency explanation of the Pulfrich phenomenon.

The classical visual latency explanation of the Pulfrich phenomenon is generalized to allow for the possibility that the visual system uses velocity information from motion detectors to compensate for spatial lag due to time lag, in identifying the instantaneous position of a moving object. The results of the reported experiment verify one consequence of the generalized version: the elliptical apparent path is skewed away from the filtered eye. The results suggest also that the extrapolation factor increases with visual latency and that there is a different extrapolation factor for each eye when the eyes are illuminated unequally.     

NEWSART: Negative binomial weighted spectral analysis in real time

In this paper, digital filters are described for concurrent adaptive estimation of the spectral powers at several target frequencies. Least-squares estimation is used, with a tapered weight function that discounts time-series data according to age. Frequency selectivity and reliability of spectral estimates are controlled by different parameters. The spectral windows are closely approximated by Student’st distribution, which is useful in the planning of experiments.     

FORTRAN subroutine for an EEG feedback digital filter

A method of constructing digital filters is outlined and illustrated in an application for research uses of EEG feedback. The method is based on least squares estimation with geometric weighting. Old data in the time series are discounted according to age, as new data arrive. Recurrence relations are used, allowing the computations to be performed in real time. A FORTRAN digital filter is formulated that simultaneously estimates (1) the spectral power in a band centered at a target frequency, (2) the total spectral power, and (3) the dominant frequency.     

Playing it by ear: Overcoming the limitations of speech synthesizers

Inexpensive speech synthesizers are now available that either plug into the card slots on computers or connect to their serial ports. With some practice in listening, the speech produced by these synthesizers is quite intelligible, and because they present information that appears on the screen of the monitor, they make it possible for blind persons to interact with computers. However, they provide only a partial solution. In too many instances, some of the text appearing on the monitor screen cannot be directed to the synthesizer, and the missing information is often crucial. This happens because the writers of application programs sometimes modify the computer’s disk operating system. This limitation can be overcome by using special hardware that reads the screen buffer directly and creates a virtual image of the screen in memory external to the computer. Because the image is updated continually, it is always an accurate representation of whatever appears on the screen. The characters contained in the external buffer can be sent to a speech synthesizer, and can be examined selectively by means of a small keyboard. Several successful hardware solutions have been demonstrated, and one of these solutions is described here in detail.     

Reviews of current books

Pastoral Psychology -     

Taming the Heathkit-Votrax speech synthesizer

Three inexpensive text-to-speech synthesizers are described, intelligibility data from a pilot experiment are reported, and software is offered that has been written to facilitate the phonemic programming of the Heathkit-Votrax synthesizer.     

In Vivo Hippocampal Acetylcholine Release During Exposure to Acute Stress

Hippocampal extracellular acetylcholine (ACh) and choline levels were evaluated using in vivo microdialysis in male Fischer 344 rats before, during, and following an 80-min exposure to two different stress conditions. Measurements were taken in rats restrained and immersed in a water bath containing either 37 degreesC (normothermic-restraint) or 20 degreesC (cold-restraint) water. Results were compared to normothermic-freely-moving rats. Cold-restrained rats displayed decreased ACh levels during cold exposure relative to both normothermic-restrained and normothermic-freely-moving rats. By the end of the cold exposure period and following removal from cold, ACh levels had returned to near-baseline values. Normothermic-restrained rats had levels similar to those of normothermic-freely-moving rats, except for a marked increase in ACh following removal from restraint. Cold-restrained rats displayed a gradual elevation in choline levels during cold stress, followed by a gradual decline after stress termination, whereas both normothermic-restrained and normothermic-freely-moving rats displayed gradual decreases during the microdialysis session. These findings demonstrate that central cholinergic neurotransmission can be altered by the application of, and removal from, acute stressors. In addition, the results suggest a possible relationship between the magnitudes of both the stressor and its cholinergic consequences.