Physique And Temperament
Factors In Behavior
That physical characteristics are largely inherited is common knowledge. Parents who are tall, slim, and blonde tend to have children who are tall, slim, and blonde. The association of temperament with physical characteristics is a more difficult problem, however. Stereotypes such as "dumb blonde," "fickle red head," and maxims such as "fat and merry, lean and sad" reveal the general acceptance of an association between physical characteristics and psychologic traits in our culture. They are found also in the world's great literature. Classic among these are the sentiments of Shakespeare's Julius Caesar: Let me have men about me that are fat; Sleek-headed men and such as sleep o'nights. Yond Cassius has a lean and hungry look; He thinks too much: such men are dangerous. Would he be fatter!
Of course, most of these stereotypes are false, even statistically, but they are reinforced in our minds by those occasional chance instances in which the physical and psychologic traits are seen in the same person (see Chapter 14 regarding superstitious responses).
Medical interest in the association between physical characteristics, temperamental qualities, and predisposition to disease dates from the Hippocratic era. However, systematic attempts to establish correlations among these three classes of variables are of more recent vintage. Most of these efforts involve the notion of constitution, a term less rigorous than genetics or heredity. Constitution refers to those enduring morphologic, physiologic, and psychologic characteristics of the individual which are largely genetically determined, environmental factors playing a comparatively minor role.
Three assumptions are implicit in most systems of constitutional types. First, they assume that constitutional traits, be they physical or psychologic, tend to occur in groups or clusters, making it possible to think in terms of types. Secondly, they assume that different morphologic and physiologic types tend to be associated with different corresponding psychologic types and that this association has a genetic basis. Third, they assume that the total constitutional complex predisposes the individual to different emotional or behavioral disorders and that this predisposition also has an hereditary basis. Two systems of constitutional types have been developed in recent years which have greatly influenced psychiatric thought as well as medicine in general. These are the systems of Kretschmer and Sheldon which will be discussed briefly.
The first edition of Kretschmer's Kopterbau and Charakter appeared in 1921. He delineated four main types of physique: pyknic, athletic, leptosome, and dysplastic. The pyknic is typically short and thick set with large body cavities but short extremities. The chest is round, the hands and feet small, and the body is generally well padded with fat. The athletic physique has a welldeveloped musculature and bony structure and the body is generally well proportioned. The leptosome is characterized by linearity of trunk, limbs, and face. The bones are small and there is little musculature. The category dysplastic covers individuals with incongruous admixtures of the other three types. It is clear that few individuals fit these idealized extremes of physique. In practice, a global assessment is made of an individual and he is placed in the category which best fits.
Kretschmer also described two opposing pathologic temperaments: cycloid and schizoid. Cycloid individuals are those who show marked and repetitive swings in mood, whereas schizoid individuals tend to be aloof, timid, and introverted. In more exaggerated form these two abnormal personality extremes correspond to two of the most common psychoses, manic depressive psychosis and schizophrenia, respectively. Kretschmer observed that cycloid individuals, and those with manic depressive psychosis, typically are of pyknic body build, whereas those of schizoid temperament, or with schizophrenia, are more often leptosomes. Studies reported by Kretschmer and others involving large groups of hospitalized psychotic patients tend to corroborate this relationship (21).
Many factors were uncontrolled in these early reports, however, such as the age of the patients as well as their racial background and occupation. For example, the incidents of manic depressive psychosis, relative to that of schizophrenia, tend to increase with age. Also there is a tendency toward more pyknic body build as age advances. When factors such as these are controlled, as in the studies of Burchard (3), much of the difference in the preponderant physique in the two conditions disappears. A slight but statistically significant association does remain, however.
Kretschmer later extended his system to include persons within the normal range of personality functioning, terming the two opposing temperamental tendencies as cyclothyme and schizothyme. However, efforts to establish an association between these temperament types in a normal population with their corresponding physiques have been largely negative (14).
Sheldon, an American investigator, has developed a system of physique and temperament typology which better reflects the continuous nature of physical and psychologic variations among individuals of the species (16). Sheldon and his associates photographed 4,000 college men in three poses: ventral, dorsal, and lateral. Eighteen anthropometric indices were derived from exact measurements made from the photographs as well as height and weight measurements. These indices are used to classify an individual according to the proportion of three basic components of structure: endomorphy, mesomorhy, ectomorphy. These terms for the three components of physique correspond to the three primary germinal layers: endoderm, mesoderm, and ectoderm. Thus, endomorphy refers to a preponderance of the digestive viscera, and the individual with high endomorphy is characterized by roundness and softness of physique. A mesomorphic individual shows preponderance of the bone, muscle, and connective tissue and is characterized by a heavy muscular physique. The ectomorphic extreme shows a preponderance of ectodermal tissues; that is, the skin area and nervous system constitute a higher proportion of body weight than in the other physiques. The ectomorphic physique is characterized by linearity with little fat and muscle.
On the basis of 18 anthropometric indices, each subject is classified on a 7-point scale in relation to each of the three basic components of physique. Thus a person at the estornorphic extreme might be classified 1-1-7, indicating small endomorphic and mesomorphic components but a high ectomorphic component. This extreme of physique and other examples of Sheldon's system are shown in Figure 1.
Sheldon's system of classification of physique has two advantages over earlier efforts. First, the assignment of an individual to a somatotype is based on objective measurements which add reliability to the procedure and make it possible for others to employ the system and obtain comparable data. Secondly, as mentioned above, it recognizes more fully the continuous nature of variation of physical traits, rather than forcing individuals into one of a small number of idealized types.
Sheldon (17) also devised a system of classification of tempera.. ments which complements his classification of somatotypes. From an intensive study of 33 young men by interview techniques, Sheldon deduced 50 psychologic traits of personality characteristics which correspond to the 18 anthropometric indices of physique. These traits determine 3 components of temperament: viscerotonia, somatotonia, and cerebrotonia. Viscerotonia denotes a tendency toward pleasure in eating, relaxation, and the company of others and need for affection, approval, and the love of others. Somatotonia describes the tendency toward assertiveness, directness in manner, love of muscular activity, competition, and the need for exercise and action. Finally, cerebrotonia refers to the tendency toward restraint and inhibition with little output of emotion and energy and a disposition for introspection, solitude, and asociability. Again a 7-point scale is used to classify an individual, according to the relative proportion of the 3 basic components of temperament in his psychologic make-up. Thus 2-4-5 indicates a small contribution of viscerotonia to the temperament but larger contributions of somatotonic and cerebrotonic components.
This system of classification by temperaments has many of the same advantages as Sheldon's system of somatotypes. The system again takes into account more fully the continuous nature of variation of psychologic traits from individual to individual than is suggested by such global theoretical constructs as schizoid or cycloid.
Sheldon and his associates (17) attempted to establish a relationship between physical and temperamental aspects of constitution by correlating measured somatotypes and temperament types using 200 university men ranging in age from 17 to M. The coefficient of correlation between endomorphy and viscerotonia was .79, between mesomorphy and somatotonia .82, and between ectomorphy and cerebrotonia .83. After intensive study of these 200 subjects, Sheldon and Stevens (17) hypothesized that discrepancies between somatotype and temperamental index predisposed the individual to maladjustment. There has been no clear confirmation of this hypothesis, however.
Efforts to replicate these findings have shown significant correlations between somatotype and temperamental index, but usually of lower magnitude (15). Subsequently, some interesting studies have established significant correlations between somatotype or temperamental index using Sheldon's systems and categories of psychiatric disorder (4). As was mentioned earlier with respect to Kretschmer's system, however, changes do occur in somatotypes with changes in nutritional status, age, and other variables. These tend to confound the interpretation of an association between somatotype or temperamental index and psychiatric disorder.
Glueck and Glueck (6) conducted a controlled study in which 500 delinquent boys were compared with 500 nondelinquent youths of approximately the same age, I.Q., national origin, and neighborhood of residence. On the whole a higher percentage of boys in the delinquent group were of mesomorphic proportions, and a significantly lower percentage of ectomorphic physique. However, there may be one other source of bias not mentioned previously. A particular physique in a given culture may predispose an individual to some kinds of activity through the mediation of social rather than genetic factors. For example, more aggressive behavior may be expected of a boy of athletic physique than a slender, frail youth of the same age. This expectation may be held by the youth's elders as well as his peers. Such social attitudes greatly affect an individual's self-concept and his behavior.
The familial or social mediation of the influence of genetically determined physical traits on personality development is also illustrated in the instance of gross congenital defects. A child born with a club foot or deformed hand may be treated very differently by his parents than his normal sibling. Open rejection of such a child during the formative years may lead to deep-seated feelings of inferiority and guilt about the defect. These in turn make difficult the normal development of personality in other areas. Alternatively, parents of the congenitally deformed child may react to their feelings of guilt and the tendency to reject their offspring with overly solicitous attitudes. Such an over protected child is shielded from many childhood stresses that are necessary in learning successful ways of dealing with problems later in life. Here again defects of personality and maladjustments may arise from genetically determined physical defects but are mediated by parental, i.e., social, agencies.
- Genetic Factors In Larger And Morecomplex Segments Of Behavior - Factors In Behavior
- The Mechanics Of Heredity - Factors In Behavior
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