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The triteness of time worn aphorisms frequently distracts from their essential truth. Such may be the case with "well begun" . . . However, this piece suggests that the saw bears considerable relevance to the undergraduate program of teacher training; that, in particular, it has relevance to the beginning course in the professional sequence referred to variously as Orientation-School and Community-The Beginning Teacher, etc. It contends that the beginning course is the most critical in the entire professional sequence, not excluding student teaching. Three assuptions sustain this conviction

Despite the continuing discovery of changes in brain chemistry and anatomy following exposure to environmental stimulation, no mechanism advanced to date has proved satisfactory in explaining the mediation of these changes. Postulated physiological mechanisms include stress, endocrine, maturational, and learning factors. Each of these mechanisms and their shortcomings have been discussed by Rosenzweig (1969; Rosenzweig et al., 1971) and so are dealt with only briefly here. Evidence is then presented to suggest that the arousal reaction (orienting response) may be a major mediating mechanism by showing that the arousal histories of stimulus-enriched and stimulus-deprived animals are different, and that the properties and consequences of the arousal reaction are such as may account for much current knowledge of environmental effects.

In a previous paper we have proposed a developmental theory to account for the neurological changes which result from differentially rearing animals in either enrichment or isolation. On the basis of brain weight measurements we suggested that the primary cause of the differential development could be traced to retarded neurological growth in the isolated animals. The present 9 studies test the generality of this theory by applying it to the cortex length changes induced in rats by differential rearing periods of between 18 and 160 days. In the light of this new data the theory has been revised to the extent that the developmental ceiling for the dependent variable is now considered to change with age instead of being fixed. Two major consequences of this revision are as follows. Firstly that the environmentally induced changes in cortical development are seen as persistent. Secondly that the Rank Order Effect is shown to be a transitory phenomenon which exists only when some, but not all of the isolate values have been restricted in their development.

Evoked cortical potentials were recorded from rats reared in either a complex sensory environment or in isolation. Potentials from enriched animals showed a decrease in amplitude with repeated somatic stimuli, whereas those from isolated animals did not. One hour after this experiment both groups showed similar decreases in potential amplitude with repeated stimulus. The results are interpreted as an habituation process whose development is influenced by early environment.

The home-cage activity of mice housed in either social or enriched sensory environments was continuously recorded for 23 days. During this period the mice were given daily injections of either strychnine, chlorpromazine, or saline. Both chlorpromazine and social rearing depressed home-cage activity. Strychnine also depressed activity, but only in the social group.

Rhode Island Red chicks were hatched either in isolation or in pairs. On the second day after hatching they were injected with either 0, 0.5, 1.5, 4.5, or 13.5 mg of testosterone. Two days later their emotional response to a novel environment was determined by counting the cheeping rate. It was found that, while low doses of testosterone elevated cheeping, the highest doses caused a depression back to, or below, control levels. The rearing environment also had an effect in that the isolated chicks cheeped more than their social counterparts for every dose except the 0.5-mg dose. It was concluded that testosterone can influence behavioral arousal in chicks but that the effect is dependent upon both dose and previous environmental experience.

While it is widely accepted that the sensory environment can modify behavior, the underlying neural changes are not well understood. However, during the last two decades many studies have demonstrated that brain structure can be modified by sensory stimulation. This suggests that the sensory environment may be used to ameliorate the neurological effects of brain damage. The evidence for this suggestion will be presented under the following headings: experimental variables, the state of the art, physiological mechanisms, and outstanding questions. We will also use the available research data to speculate upon the etiology of both damaging and repair processes.

Summary 1. Test type preference of 227 medical students was investigated by means of a questionnaire. 2. A majority of students believed that MCQ examinations gave rise to less advance anxiety than other forms of examination. 3. There was a highly significant correlation between preference and performance, probably as a result of reciprocal reinforcement between them. 4. A multiple linear regression analysis revealed that the scales stability/neuroticism, extraversion/introversion, general mental ability and native language had a significant influence on test preference. There was a significant trend for confident, stable students to demonstrate preference for MCQ while tense, anxious students tended to prefer other test types. 5. We conclude that a mixed examination format is desirable not only on theoretical grounds, but was also preferred by these students.

The study was an attempt to explicate the results of recent research concerned with the stress-buffering effects of received social support for individuals with internal locus of control perceptions. In addition to measuring received support, perceptions of availability of support were measured; further, a proximal measure of stress was substituted for the negative life events measure of stress. Evening class business administration students who were older than the typical undergraduate served as volunteer participants. Results of the cross-sectional analyses are consistent with previous research with respect to received support as hypothesized; however, an opposite or "negative" buffering effect for internals is obtained when the measure of support is perceived reassurance of self-worth. Main effects of perceived social support, but not received support, are obtained for externals but not (with one exception) for internals. These findings are discussed in terms of their implications for the study of coping with stress.

One group of rats was reared under conditions of environmental complexity, while their littermates served as isolation controls. The occipital cortex was 4.9% (p < 0.01) and the hippocampus 5.7% (P < 0.05) thicker in the environmental complexity rats than in the isolation control animals. Differntial cell counts demonstrated significant differences in neuroglia in the hippocampus. Copyright

ANIMALS that have been exposed to environmental stimulation develop marked differences in brain structure and biochemistry when compared with animals that have not been exposed in this way1–4. Factors influencing the magnitude of these changes are the duration of rearing and the age of the animals when the environmental separation takes place. Most studies have focused on young animals because the brain is thought to be more plastic at this stage. As a result, temporal analyses of the induced changes have usually been limited to fairly short periods of environmental exposure early in the animal's life. Rosenzweig et al.3 have suggested that, in rats differentially reared from weaning, the induced differences in brain weight reach a maximum during the first 30 d of separation, after which they decrease. But the evidence for this biphasic response has been based on relatively short periods of differential rearing (15–160 d).

In previous reports exposure to 80 or 90 days of environmental complexity induced a significant increase in the length of the rat cerebrum, whereas 30 days' exposure induced changes which failed to reach significant levels. In the present study after 30 days of differential rearing, cerebral length was 1.2% (p < .005) greater in brains from the enriched animals; the region contributing to this increase lay between the anterior pole and the point of greatest cerebral width. Measurements of cerebral width and brain weight failed to show any significant change, but the body and adrenal weights of the isolated rats were 19.9% (p ≤ .02) greater, respectively, than those of their littermates reared in environmental complexity. However, the ratios of adrenal weight to body weight did not differ significantly between groups.

Two groups of rats were reared under conditions of environmental complexity while their littermates were reared in isolation. Cerebral length and width were measured following 30 and 80 days of differential rearing. In the 30‐day group differences in neither cerebral length nor width reached significant levels but the product of the 2 parameters was 2.1 % (p < .02) greater in the stimulated animals. In the 80‐day group cerebral length was significantly greater (p < .001) in the stimulated animals than in their isolated littermates, but no significant differences in cerebral width were detected.

In this longitudinal study, stress attributed by parents to their family member with intellectual disability was investigated over a period of seven years in relation to specific foci of parental worry, and also in relation to stress attributed to the youngest sibling without a disability. The stress parents attributed to their family member with a disability was about double that attributed to the youngest sibling without a disability. However, multiple regression analysis revealed that the stress attributed to the sibling without a disability actually accounted for most of the variance in explaining the stress attributed to the family member with a disability. It is concluded that the stress attributed to any specific child may be an indicator of more general family stress. It was also found that, while the strength of parental worry decreased from time 1 to 2, the pattern of worries did not change over time, and nor did the specific foci of worry differentiate low-stressed from high-stressed parents. I...

Most of the effort directed at understanding the problems of allergy has focused on the interacting components of the immune system. The possibility that histamine may be released as a learned response has now been tested. In a classical conditioning procedure in which an immunologic challenge was paired with the presentation of an odor, guinea pigs showed a plasma histamine increase when presented with the odor alone. This suggests that the immune response can be enhanced through activity of the central nervous system.

Considerable research supports the widespread complaint of mood and behavioral changes during the menstrual cycle. However, there is little evidence of effects on intellectual performance, even though students commonly complain of it. We studied the results obtained by 244 female medical and paramedical students in all examinations taken during one year. In view of suspected correlations between personality characteristics and degree of dysmenorrhea, an Eysenck Personality Inventory, measuring extroversion and neuroticism, was administered. The examination results of high and low scorers on these personality scales and of those women with prolonged (greater than or equal to six days) menses were reanalyzed. Not one of these analyses revealed significant menstrual-cycle effects on examination performance. Thus, while some persons may suffer, it does not seem that menstrual cycle effects are sufficient to handicap significantly the examination performance of the majority of female students.