Design and operation of an EEG-based brain-computer interface with digital signal processing technology

We are developing an electroencephalographic (EEG)-based brain-computer interface (BCI) system that could provide an alternative communication channel for those who are totally paralyzed or have other severe motor impairments. The essential features of this system are as follows: (1) EEG analysis in real time, (2) real-time conversion of that analysis into device control, and (3) appropriate adaptation to the EEG of each user. Digital signal processing technology provides the speed and flexibility needed to satisfy these requirements. It also supports evaluation of alternative analysis and control algorithms, and thereby facilitates further BCI development.     

Book reviews

SANDERS, A. F. (Ed.). Attention and Performance III. Amsterdam: North Holland Publishing Company. 1970. Pp. viii + 442. (Price not known.)

CORCORAN, D. W. J. Pattern Recognition. Harmondsworth: Penguin Books Ltd. 1971. Pp. 223. £0.50.

SCHRIER, A. M. and STOLLNITZ, F. (Eds.) Behaviour of Nonhuman Primates Vol. III. New York: Academic Press Inc. 1971. £4.45.

KINTSCH, W. Learning, Memory, and Conceptual Processes. New York: Wiley and Sons. 1970. Pp. 498. £4.40.

MORTON, J. (Ed.) Biological and Social Factors in Psycholinguistics. London: Logos Press. 1971. Pp. 215. £3.50.

RITCHIE RUSSELL, W. The Traumatic Amnesius. London: Oxford University Press. Pp. 84. £2.00.

MILLER, N. E. Selected Papers. Chicago: Aldine Publishing. 1971. Pp. 874. £15.00.

SUTHERLAND, N. S. AND MACKINTOSH, N. J. Mechanisms of Animal Discrimination Learning. New York: Academic Press. 1971. Pp. 559. $18.50.

FURCHTGOTT, E. (Ed.). Pharmacological and Biophysical Agents and Behavior. New York: Academic Press. 1971. Pp. xii+402. $14.50.

EYSENCK, H. J., ARNOLD, W. AND MEILI,R. (Eds). Encyclopedia of Psychology. Volume I. London: Search Press. 1972. Pp. 396. £8.00.     

Counselors Teaching Peaceful Conflict Resolution

Conflict resolution theory suggests that the constructive, prosocial, integrative style is best for resolving interpersonal conflict, because it not only solves the problem but also enriches the interpersonal relationship. Effective interpersonal communication is the critical element of this integrative process. Counselors could prepare people to resolve interpersonal conflicts skillfully, effectively, and peacefully.     

Isolating the effects of symbolic distance,and semantic congruity in comparative judgments: An additive-factors analysis

The time needed to compare two symbols increases as the cognitive distance between them on the relevant dimension increases (symbolic distance effect). Furthermore, when subjects are told to choose either the larger or the smaller of two stimuli, the response time is shorter if the instruction is congruent with the overall size of the stimuli (semantic congruity effect). Three experiments were conducted to determine the locus of these effects in terms of a sequence of processing stages. The developmental aspects of these effects were also evaluated, as the subjects were from kindergarten, first grade, third grade, fifth grade, and college. By varying the visual quality of the stimulus in each experiment, it was determined that the distance effect resides in a comparison stage, whereas the congruity effect is an encoding phenomenon. Both distance and congruity effects were present at all grade levels, but they decreased in magnitude as grade increased. The results were interpreted relative to recent models of comparative judgments.     

The lateralized effects of concurrent cognitive and motor performance

Subjects were required to simultaneously tap two button switches, at two different distances apart, while at the same time performing a running memory span (RMS) task of either words or faces. Performance on the button-pressing task was assessed in terms of both speed and consistency. When the switches were close together, both of these measures showed leftand right-hand performance to be selectively disrupted by concurrent performance of faces and words memory tasks, respectively. With the switches further apart, selective disruption of the contralateral hand occurred only with thespeed index. Using the consistency index, however, bilateral disruption was observed with both types of RMS tasks. Error and d’ performance on the words and faces RMS tasks was only disrupted by contralateral manual activity. Some implications of these results for neuropsychological models of brain lateralization of function are discussed.     

The role of attention in the disinhibition of displacement activities

A mechanism for the disinhibition of displacement activities is proposed, by which a factor arising from non-reward causes attention to be switched to irrelevant aspects of the stimulus situation. In addition to evidence already extant, three lines of evidence are presented for the case of displacement pecking in the Barbary dove: (1) partially rewarded doves learn more about incidental aspects of a discrimination situation than consistently rewarded doves; (2) partially rewarded doves respond more readily to irrelevant stimuli than consistently rewarded doves; (3) doves which take longest to extinguish a simple approach response, also spend most time displacement pecking.     

Preliminary evaluation of an after-school resistance training program for improving physical fitness in middle school-age boys

Most after-school physical activity programs for youth focus on aerobic games and activities. The purpose of this study was to evaluate the efficacy of an after-school resistance training program on improving the physical fitness of middle school-age boys. 22 boys (M = 13.9 yr., SD = .4 yr.) participated in a periodized, multiple-set, 9-wk. (2x/week) resistance training program. All subjects were pre- and post-tested on their 10-repetition maximum squat, 10-repetition maximum bench press, vertical jump, medicine ball toss, flexibility, and also percentage of body fat and the progressive aerobic cardiovascular endurance run (PACER). Statistical analysis indicated that subjects significantly improved performance on the squat (19%), bench press (15%), flexibility (10%), vertical jump (5%), medicine ball toss (12%), and the PACER (36%). Although this design minus a control group limits interpretation, this after-school resistance-training program can improve muscular fitness and cardiovascular fitness in boys and should be replicated with appropriate experimental controls.