Production and control of auditory signals in attention research using the Apple-Psych system

A technical issue in auditory spatial attention research is how best to provide low-cost, accurate control of the frequency, duration, and location of acoustic signals. Three solutions to the problem are compared: use of the internal oscillator of the Apple lIe, use of a Mountain A/D+D/A card, and use of an external oscillator chip. The unique advantages and drawbacks of each system are discussed. All share some common problems of external speaker interface, timing control, and interface with the software. Hardware and software solutions implemented on the Apple-Psych system are discussed, along with data that demonstrate the precision control achieved with the system.     

A simulation-based tutorial system for exploring parallel distributed processing

This article presents a simulation-based tutorial system for exploring parallel distributed processing (PDP) models of information processing. The system consists of software and an accompanying handbook. The intent of the package is to make the ideas underlying PDP accessible and to disseminate some of the main simulation programs that we have developed. This article presents excerpts from the handbook that describe the approach taken, the organization of the handbook, and the software that comes with it. An example is given that illustrates the approach we have taken to teaching PDP, which involves presentation of relevant mathematical background, together with tutorial exercises that make use of the simulation programs.     

Repairing the Microsoft BASIC RND function

Difficulties with the Microsoft BASIC function for generating random numbers (RND) are cited and new problems reported. Fixes are suggested that allow use of some of the speed of the original function and that produce greatly improved pseudorandom numbers. A published generator is combined with the RND function as a compromise solution.     

The languages we use

Members of the Society for Computers in Psychology responded to a survey concerning their programming practices and language use. The results reveal current hardware and software use; relationships among computer science training, task, and language choice and usage; and areas in which attention to some structured programming principles might improve the code that psychologists write.     

A high-gain,low-noise amplifier for EEG

This paper describes an amplifier for an electroencephalograph with gain of 1×10⁴ to 1×10⁶ and made entirely of commercially available IC components. The two-stage amplifier has a preamplifier stage with fixed gain of 1000, and a second stage with variable gain from 1 to 100. The final stage, an anti-aliasing filter, adds a gain of 10 to the signal. The circuit has high common mode rejection, low input bias current, very low noise characteristics, low offset voltages, and offset nulling capability built into the circuit.     

The relative autonomy of schools and educational interventions for substance abuse prevention, sex education, and gender stereotyping.

This paper evaluates intervention programs in schools using the theoretical framework of the critical sociology of education, and most specifically, the extent to which schools are autonomous from the larger society. Three different types of intervention programs are reviewed: drug abuse prevention, sex education, and programs to change gender stereotypes, all of which were found to have limited effectiveness. Schools appear unable to change behaviors which are prevalent in a culture because they themselves are strongly influenced by that culture, and because adolescents are influenced by forces outside school. To be effective, such interventions would seem to require governmental agencies, community groups, and the media to work with the schools in order to influence the culture and thus produce behavioral changes in individuals.     

A comparison of the psychological profiles of teenage mothers and their nonmother peers: I. Ego development.

Two projective techniques were employed to explore the psychological characteristics of teenage mothers who were found, in a previous study, to have experienced more traumatic childhoods than the nonmother control group. Part I, presented here, investigated ego development using the Loevinger Sentence Completion Test. (Part II, responses to a set of TAT cards, will appear in a subsequent issue of Adolescence.) In comparison with the nonmothers, teenage mothers demonstrated more mature ego development. This is in distinct contrast with most reports in the literature, and the ramifications of these results are discussed. In addition, content analyses of the responses to the Sentence Completion Test confirm the highly involved mother-daughter and negative father-daughter relationships found in the previous study with this sample.     

Runaway girls in distress: motivation, background, and personality.

This paper deals with girls aged 13 to 21 who have run away from home. Social workers who work with such girls point out that they are not a homogeneous population and that their motives can be very different. This study divides their motives for running away into two types, "running from" and "running to," and describes the specific personality traits associated with each. Findings indicate that girls who "run to" are younger, more impulsive, have an internal locus of control and a history of more runaways and longer periods of staying away from home. Girls who "run from," on the other hand, are older, more reflective, have an external locus of control and a history of fewer runaways and shorter periods away from home.