Describes two studies of brain hemisphere development which indicate children retarded in the functions of one hemisphere may not be retarded in the functions of the second hemisphere. Suggests that the left hemisphere functions may inhibit some right hemisphere functions. (SL)

Acoustic studies of speech development are surveyed and the data is discussed with respect to the anatomical and neuromuscular maturation of the speech mechanism. (Author/SBH)

A review of epidemiological studies suggesting that exercise reduces the risk of cancer concludes that exercise may help defend against cancer by preventing obesity, stimulating lymphokines, and/or facilitating other healthful changes in behavior. (Author/CB)

Hypothesized that when relative dietary intake of tryptophan per capita is low compared to other amino acids, less serotonin is formed in brain neurons, and suicide rates tend to be high. Data from Canada, Australia, New Zealand, the United States, the United Kingdom, and Ireland support the hypothesis for males and for both sexes combined.…

This study examining the effect of a 10-week hydraulic resistance exercise program on serum androgen levels, strength, and lean body weight in 18 college women revealed that training did not result in significant increases in androgen hormones, although there were significant gains in strength. (Author/CB)

Nine 18- to 29-year-old females were studied while jogging and skipping at treadmill speeds of 4.0, 4.8, and 5.4 miles per hour. Comparison of metabolic demand, musculoskeletal stress, and perceived exertion indicated skipping imposed significantly greater metabolic demands and caused higher heart rates than jogging. Skipping was also rated more…

Investigated cause of abusive drinking among the elderly and treatment practices and counseling strategies used by professionals who serve them. Structured interviews with six practitioners who were knowledgeable about alcohol abuse among the elderly revealed consensus that alcoholism is a physiological disorder with attendant psychological and…

Obtained thresholds for octave-band noises with center frequencies of 0.4, 1, 2, 4, and 10 kHz and 1/3-octave band noises centered at 10 and 20 kHz from children aged 6 to 16 years. Compared results with findings for infants, preschool children, and adults. Continuing sensitivity improvements were evident from infancy well into the school years.…

As devices for measuring physical activity become more accurate and economical, researchers use them to study topics ranging from the aerobic capacity of children to the job performance of military aircrews. This article discusses various activity monitoring devices and their application. (Author/JL)

An introduction to terms and concepts associated with resistance training is given. Sports associated with this training, such as power lifting and body building, are described. The merits of free weights versus resistance machines are discussed. The article recommends a training program for beginners. (Author/JL)

A comparison of vocal development in deaf and hearing infants indicates that well-formed syllable production is established in the first 10 months of life by hearing infants but not by deaf infants, suggesting that audition plays an important role in vocal development. (PCB)

A series of computer simulations of the neuronal resting and action potentials are described. Discusses the use of simulations to overcome the difficulties of traditional instruction, such as blackboard illustration, which can only illustrate these events at one point in time. Describes systems requirements necessary to run the simulations.…

A panel of eight experts discuss the cardiovascular, lipoprotein, weight control, and psychological benefits of exercise on health. The challenge of motivating people to exercise regularly is explored. (Author/MT)

The authors critically examine the research on physical activity in the elderly to assess the elderly's capacity for exercise and the benefits accruing from exercise. Lower-intensity exercise programs attract a more representative group of senior participants and overcome many barriers. Implications for program planning and efforts are discussed.…

Explains the mechanisms and describes the processes that underlie gravitropism in roots. Reviews experimental efforts and investigative results that explored the causes of root behavior. (ML)