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The presence of neurons in macaque temporal cortex and amygdala which fire selectively in response to social stimuli has been demonstrated by several investigators. The extent to which such neuronal populations may respond to a broad range of social features, including expressive movements and interactions, has not been fully explored due to the difficulty of presenting such complex stimuli in a controlled fashion. We describe a method for presenting moving segments of macaque behavior, visual and auditory, to animal subjects during single unit recording. The method permits a broad range of stimuli to be used both as probes and as controls. In addition, a novel technique for monitoring eye position in alert macaque subjects is described. We present results from the medial amygdala and adjacent cortex, demonstrating that neurons in these regions respond selectively to features of the social environment.

Working memory is disrupted an Alzheimer's disease and stroke; therefore, any therapeutic drug should deficits in working memory. The win-shift foraging paradigm has been demostrated to be a model of working memory in rats. In the present study, this paradigm was adapted to mice because of the greater ease and economy of testing potential drugs in mice and the wider availability of strains of aged mice with naturally occuring working memory deficits. This study has demostrated strain differences in the working memory trace and that age induces a deficit that can be dete4cted at 11 months af age in mice. Tacrine and physostigmine enhance the memory trace in normal mice and physostigmine can reverse age-induced working memory deficits in subjects with mild and moderate deficits but not in subjects with severe deficits.

This report is a replication of a study conducted 10 years ago by Person et al., investigating gender differences in sexual behaviors and fantasies in a college population. We found that men continue to fantasize more than women, but the gender differences have narrowed. Recent sexual experiences of our population show a trend toward an increase in gender differences, and there is a greater correlation between sexual fantasy and experiences in women than in men. As in Person's study, we did not find that men had more aggressive/sadistic fantasies than women.

In a previous publication, we reported on the effects of 10 mg/kg i.m. injections of methaqualone on behavioral changes in treated animals and untreated members of a well-established colony of 10 rhes

This experiment observed the effects of dorsolateral frontal cortex ablations on quantified social interactions of stump-tail macaques within the context of the social behavior of a larger group. A caged group of 11 stump-tail macaques, six females and five males, was observed for 100 hours pre-operatively. Post-operatively, five operates and five sham operates matched for sex, age, and rank were observed for 110 hours. Aggression increased following surgery. The female operates ranked No. 3 and No. 5 were seen to fall to the bottom of the dominance hierarchy two months after surgery. The fall in dominance as measured by displacement behavior was found to permeate several behavioral categories including presenting, threatening, and aggression. The female operates appeared to fall in inverse relationship to their ranks. The male operates showed minimal disruptions after surgery. The length of the time between surgery and the outbreak of violence might represent the length of time required for subordinates to notice and confirm the behaviors resulting from attentional defects in the high-ranking female operates.

PSYCHOANALYTIC and other psychological schools have long held that non-verbal communication (NVC) is of vital importance in human interaction. Tomkins1~2 for example, has built a whole theory of personality around the exigencies of facial affect. As Abercrombie3 has noted: “We speak with our vocal organs, but we converse with our whole body”. While NVC can convey information, as in the American Sign Language for the deaf; and the verbal mode can sustain interpersonal relations, as in informal chat; normally NVC and verbal communications play contrasting roles.4 NVC is used to manage the immediate social situation. Verbal communication is used to convey information connected with shared tasks or problems. 4 It is usually gesture, posture, tone of voice, and facial expressions (NVC) which combine to communicate the emotional base from which words are being exchanged. For ‘example, Argyle et al. 5 have found that non-verbal cues were almost five times more powerful in effecting judgments of inferiority-superiority, than verbal ones. In this context, the old adage “actions speak louder than words” is lent some scientific support. For our study of non-verbal behavior among an inmate population, we received impetus and some direction from the same discipline that has stimulated burgeoning interest in NVC in social science: ethology. Ethology refers to the biological study of animal behavior and is often used, as in ethological, to indicate a focus on NVC. The zoologists who pioneered the field developed systematic techniques for describing and analyzing NVC in their studies of animals, who cannot talk. The productivity of the application of these techniques in human research is attested to by five major works which have been published during the past few years?1°

In an established social group of rhesus monkeys (Macaca mulatta) consisting of 1 adult male, 6 adult females, 1 adolescent male and 2 infants, 3 subjects were selected to study the effects of intramuscular methaqualone (10 mg/kg) on behavioral changes in the treated animals, as well as the rest of the colony. Three drug trials alternating with saline controls were given to the dominant male, a mid-ranking female and the adolescent male. 20 h of observations were made prior to treatment to serve as a baseline, using 40 discrete behaviors. For each drug and saline period, 2h of continuous observation was directed towards each target animal (total 36 h), and 12-min behavioral samplings were carried out on each untreated subject in the colony (36 h). Dependent upon the sex and social rank of the subject, different behavioral changes occurred during drug treatment, which were consistent from trial to trial.New behaviors were observed, such as active grooming, autofellatio and masturbation in both males, while some previous behaviors disappeared or decreased. The mid-ranking female showed an increase in aggressive behavior. A biphasic action of the drug was also observed in all subjects. During the first 80–100 min, the males were mainly passive or engaged in grooming, but after this primary phase, they started either to masturbate or autofellate. After approximately 2 h, the social status and behavior of the animals returned to predrug levels. During the drug treatment, marked changes occurred in the behavior of other colony members, e.g. when the dominant male''s vigilance was lowered, the highest ranking female replaced him in rank.In general, affiliative activities were increased under the influence of methaqualone, manifesting themselves mainly in grooming, huddling or sitting together: phenomena somewhat parallel to those described among humans taking the drug in group settings.

This study examined the role of the orbitofrontal cortex in the integration and expression of aggressive behavior in the vervet monkey ( Cercopithecus aethiops sabaeus ). Operated and unoperated controls were observed in two settings: In one they were confronted by a human observer and in the other they were members of a social group of conspecifics. Nine animals (four males and five females) underwent orbitofrontal lesions. Operated males and females threatened a human observer more postoperatively than preoperatively, but exhibited no change in the rate of aggressive behavior expressed toward conspecifics. However, operated monkeys were less effective in their aggressive encounters with conspecifics. Operated males lost a greater proportion of dyadic encounters; operated females participated less successfully in coalition-mediated aggression. The postoperative changes exhibited by vervets differed from those reported in rhesus monkeys ( Macaca mulatta ), which suggests that there may be considerable interspecific variability among Old World monkeys in the effects of orbital frontal lesions on aggressive behavior.

A social group ofM. speciosa were observed in a laboratory enclosure and subsequently transferred to a 1/2 acre corral. Lesions of the baso-lateral amygdaloid nuclei inM. speciosa resulted in a disruption of affiliative behavior which did not recover over a three month period of continuous observation. Qualitative and quantitative measures indicated that no recovery in social isolation was evident. Social stress produced transient cohesiveness. Polymorphus sexual behavior increased in both operates and normals while in a laboratory enclosure but was absent when placed in a 1/2 acre enclosure. Plasma testosterone levels were related to social rank in both males and females. Alterations in dominance in the postoperative period were followed by concomitant changes in testosterone levels.

Bilateral olfactory bulbectomy was performed on the rhesus macaque (M. mulatta) at 6 to 8 months of age. Social interaction and plasma testosterone levels obtained at approximately 2-1/2 years of age indicated that early olfactory bulb ablation resulted in higher levels of aggressivity concomitant with lower levels of social facilitory behavior. Bulbectomy did not interfere with the development of normal sexual posturing and orientation at the juvenile stage. Lower testosterone levels in the anosmic females indicated possible delay in the onset of puberty, while no differences were found in testosterone between the anosmic and control males.

The influence of central nervous system lesions as well as species difference upon the response to a 0.5 gm./kg. intravenous glucose load has been evaluated in two primate species. The glucose, insulin, free fatty acids (FFA) and growth hormone response of four control M. mulatta did not differ significantly from that of three monkeys sustaining lesions of the amygdaloid nuclei or four animals with cortical lesions. However, glucose levels were lower and FFA levels higher in eight studies in six M. speciosa following cortical lesions compared to six control M. speciosa. The glucose disappearance rate (Kt) was significantly higher in the operated M. speciosa. After intravenous glucose administration, the M. speciosa group had a significantly lower glucose response and a higher insulin response than did the M. mulatta. Free fatty acid levels were lower in control M. speciosa compared to M. mulatta, but higher in operated M. speciosa. Reserpinization or acclimatization to a primate chair did not alter the glucose and insulin response of M. mulatta.

The admitting hemoglobin and hematocrit of 226 male patients in 3 Chicago hospitals was compared to the same values for 128 male graduate students and employees of the same institutions. Know current medical disorders were considered reason for exclusion from the study. The criteria for polycythemia of stress was both hemoglobin in the range of 16–18 g.% and hematocrit in the range of 50–56 per cent. The patient population showed an incidence of 19⋯0 per cent cases copared to 7 per cent for the controls (p The results were felt to confirm the association of chronic emotional stress with moderate elevations of hemoglobin and hematocrit.

Electrical stimulation of the amygdala and hypothalamus was carried out in thirty kittens varying from 4 hours to 50 days of age. Somatomotor responses were consistently elicited from both areas and at all ages studied. Beginning in the second week of life most autonomic responses could be evoked from the hypothalamus before they could be evoked from the amygdala. Initially, affective defense reactions were obtained from hypothalamic locations at 12 days and similar responses from the amygdala by 3 weeks of age. The functional maturation of the hypothalamus for autonomic and behavioral responses precedes the amygdala.

Although the central and stable position of female rhesus monkeys in semi-free-ranging bands has been observed and described, the position of the developing male in the social group is not as well delineated. The present study is an attempt to describe interactions of 18 males with members of their families. Quantitative observations were made on one band (E) of rhesus monkeys on Cayo Santiago. Incidences of behavior recorded were joining, grooming, and threatening. The resulting data were analyzed by comparing the behavior of the males studied toward members of their genealogy as well as unrelated members of the social group. Behavior of family and non-relatives toward the males was also revealed. Statistical analysis revealed that the male subjects engaged in more positive social interactions within the matrifocal family than with other members of the genealogy, and in turn, more such behavior was observed within the genealogy than with unrelated monkeys. Threatening behavior within the genealogies was infrequent. Age effects were noted in that family members directed more interactions toward younger males and as males matured, they groomed more but joined family members less frequently. These data suggest mechanisms of socialization within the genealogy that may be different from those employed within the unrelated social group.

Summary Bilateral ablations of dorsolateral frontal granular cortex were performed in four monkeys prior to the 35th postnatal day and in three monkeys at 3 years of age. Subsequent testing procedures involved the learning of a color discrimination, a series of delayed response tests and a delayed alternation task. No differences were found between early- and late-frontals in learning the color problem. All animals were equally impaired in delayed alternation performance. Delayed response testing revealed a marked superiority for early-frontals, relative to the performances of later-frontals. Differential delayed response performances of the two frontal groups were not due to differences in either surface lesion or retrograde thalamic degeneration. It was concluded that either a compensatory neural reorganization or a progressive cerebral maturation might account for the sparing of delayed response capacity in the early frontal preparations.

IT IS now well established that plasma levels of 17-hydroxycorticosteroid (17-OHCS) may be used as an indicator of emotional arousal. Investigations into the relationship between a variety of psychological states and changes in 17-OHCS levels have largely been concerned with such emotions as anger, anxiety, fear, coping ability, depression and stressful life situations [l]. In general, these studies conclude that these emotional states are accompanied by increase in plasma 17-OHCS levels. In an exhaustive review, Mason [2] concluded that elevations of 17-OHCS are not related to any specific affective state but “reflect a relatively undifferentiated state of emotional arousal or involvement, perhaps in anticipation of activity or coping”. Novelty, and disorganizing emotional reactions have been found to be particularly effective stimuli. In the same review, Mason suggests however, that there have been no studies dealing directly with pleasurable arousal states and 17OHCS levels. As part of a larger study concerned with the effects of sexually arousing visual stimuli in man, we have studied plasma levels 17-OHCS as one of several physiological concomitants of sexual arousal. An initial study on the effects of an erotic movie on sleep and dreams has been published earlier [3]. Subsequently, 3 additional studies using different groups of subjects have been done. In each study, blood samples were drawn for determination of the individuals plasma 17-OHCS response to the erotic films. Since it has also been well established that there is considerable variation between subjects [2] our attempt was not to study groups as such, but individuals, each exhibiting a unique life history, defensive structure, sexual interests and with differing values of what constitutes erotically stimulating material. The major question posed by this investigation is the effect of sexual arousal on the plasma levels of 17-OHCS. Since sexual arousal is an emotional state which probably has a neuro-anatomical substrate distinct from those emotional states of fear, anger and anxiety than we might expect it to also have a different influence on the hypothalamic-pituitary-adrenal cortical response.

The individual and social behavior of 15 cats and 18 rhesus monkeys was recorded and analyzed during a control period of from 3 to 15 months, during which the animals were also trained to solve increasingly complicated problems. Adaptational conflicts were used to induce persistent experimental neuroses in 3 kittens, 2 cats, 3 young monkeys and 8 adult ones. The amygdalae were then totally ablated, with some injury to the surrounding areas, in 6 of the cats and all of the monkeys; in the remaining 9 cats only the lateral or the medial amygdalae were removed. Postoperatively, the cats exhibited: 1. no general amnesia for previous learning; 2. only mild amelioration of neurotic behavior; 3. moderate motor restlessness; 4. variable sexual drive including a phase of hypererotism; 5. markedly altered interactions with other cats and humans; 6. slowed re-learning due to low motivation and erratic or perseverative performance on both simple and complex tasks; and 7. severe disorganization of adaptive behavior af...

Lesions to the olfactory stalk, medial olfactory area, and hippocampus were produced in rats at 3–19 days of age. Delayed puberty occurred in the females with bilateral olfactory stalk and medial olfactory area lesions. Unilateral lesions of the olfactory stalk were also effective in delaying vaginal opening. Deficiencies in growth and smaller endocrine organs occurred in both sexes with a variety of lesions. Early handling affected final body and adrenal weights in both operated and control rats.

Our preliminary observations lead us to conclude that members of M. speciosa made excellent subjects for behavioural and neuropsychological investigations. To judge from their learning scores, rich behavioural repertoire, and social interaction, these monkeys are at least as intelligent as M. mulatta. They have proved to be naturally docile and submit readily to laboratory routine. Since they are so easily managed, we regard them as superior to M. mulatta for investigations where handling becomes necessary.

environment. Recent field studies of the social behavior of a variety of subhuman primates have emphasized the rich repertoire of social interactions and their adaptive significance for the species.l-3 These studies have also emphasized the differences in individual as well as social behavior that exists between species of primates. However, these differences have generally not been an important consideration in assessing the behavioral changes occurring from experimental brain injury. Therefore, a series of experiments have been planned to study the effects of brain lesions on social behavior both in the laboratory and in the field in several species of Old-World monkeys. Eventually, it may be possible to define more clearly those aspects of a syndrome which are species specific, as well as other aspects which are characteristic of most subhuman primates. Comparison of the behavioral changes seen in the field with those observed in the laboratory may help to clarify the influence of caging and to make laboratory observations more pertinent. For the present experiment we chose to ablate the amygdaloid nuc1ei.S Under laboratory conditions, bilateral lesions of the amygdaloid nuclei in the individually caged, adult rhesus monkey (M. mulutta) results in a syndrome of relative docility, especially toward man, hyperorality, coprophagia and hypersexuality.4 Two studies have examined the effects of amygdalectomy on social interaction in groups of laboratory housed macaques. ROSVOLD, MIRSKY and PRIBRAM~ have reported that

In an attempt to specify physiologically the emotional states of sexual arousal and anxiety occurring independently and/or simultaneously, male subjects were shown two erotic movies (one heterosexual and one male homosexual) and a suspense movie, while pupil size, heart rate and plasma 17-hydroxycor

An elevated plasma 17-OHCS was observed in rats self-stimulating for 1 hr., especially those implanted in the region of the medial forebrain bundle in the hypothalamus. This is interpreted to mean that ACTH was released and thus a stress response occurred despite the fact that intracranial shock in these brain sites has reinforcing properties.

In summary, the results of early amygdala lesions revealed no growth deficit, no stupor in animals operated prior to 72 days of age, slight acceleration of somato-motor development, and no differences in the time of appearance of play and aggression. Transient hypersexuality first appeared in the operated animals at six months of age, and in some, heightened agressiveness became apparent at the time. Ovarian hypertrophy was the only notable effect of early amygdala lesions on endocrine development.

Ss, 13 Macaca speciosa, 7 Macaca mulatta and 10 Macaca ira monkeys were restrained for 24 hr. Before and after restraint blood samples were drawn from 18 but only once from 12 monkeys. Plasma 17-OHCS levels of all species increased after restraint. Findings are related to genetic and stress factors.

Adult metachromatic leukodystrophy is a demyelinating disease due to an inherited lack of arylsulfatase A activity. The purpose of this paper is to present the characteristics of this disorder as they occurred chronologically in two siblings, prior to and subsequent to the appearance of gross neurological deficits. A deficit in spatial relationships, as contrasted with verbal abilities, was observed initially in both cases at age 13. Initial psychiatric symptoms were noted at age 16 and 18, with both patients being diagnosed subsequently as schizophrenic. Gross neurological deficits were observed 2 and 13 years, respectively, after the appearance of psychiatric symptoms. A deficit in spatial relationships may be a very sensitive early indicator of adult metachromatic leukodystrophy.

Two studies assessed (1) the effect of medroxyprogesterone acetate (MPA), Depo-Provera, on socio-sexual behaviors, and (2) the interaction between socio-environmental conditions and MPA treatment effects. Study One utilized two males and eight female members of a semi-free-ranging island colony. Females received 30 or 100 mg MPA IM or were untreated. Study Two used three laboratory-housed pairs of tubal-ligated females, observed during 30 min behavior tests with one of three males. Sexually preferred females received 30 mg MPA IM. Semi-free-ranging treated females received fewer ejaculations than untreated females and did not copulate for up to 68 days post-treatment. Rates of grooming were not affected. In the laboratory tests, mean rates of ejaculations per test were reduced for treated females but increased for untreated females, and untreated females groomed males more than did treated females. Contrary to previous studies, these results suggest that stumptail macaque sexual behavior can be influenced by hormones but this influence is modulated by socio-environmental factors.

New Perspectives in Psychiatry: Relevance of the Psychopathological Animal Model to the Human.- I. Instinctual and Environmental Learning.- Factors Affecting Responses to Social Separation in Rhesus Monkeys.- Human Personality Development in an Ethological Light.- Discussion of Suomi and Bowlby Chapters.- Prenatal and Postnatal Factors in Gender Identity.- Workshop I (Moderated by Harry F. Harlow).- II. Conflict of Adaptation to Changed or Induced Environmental Conditions.- Phylogenetic and Cultural Adaptation in Human Behavior.- Unpredictability in the Etiology of Behavioral Deviations.- Animal Models of Violence and Hyperkinesis: Interaction of Psychopharmacologic and Psychosocial Therapy in Behavior Modification.- Coping Behavior and Neurochemical Changes in Rats: An Alternative Explanation for the Original "Learned Helplessness" Experiments.- Discussion.- Workshop II (Moderated by Howard F. Hunt).- III. Neurophysiological Experimental Modification of the Animal Model as Applied to Man.- The Use of Differences and Similarities in Comparative Psychopathology.- Animal Models for Brain Research.- Drug Effects on Foot-Shock-Induced Agitation in Mice.- Indole Hallucinogens as Animal Models of Schizophrenia.- Discussion.- Animal Models for Human Psychopathology: Observations from the Vantage Point of Clinical Psychopharmacology.- Workshop III (Moderated by Ronald D. Myers).- Concluding Remarks.- The Significance of Ethology for Psychiatry.- Index of Names.

Lesions in the amygdaloid nuclei have different effects on male and female monkeys. While there is typically a redirection in aggressive behavior, and changes in sexual behavior, there are also instances of heightened aggressivity. This paradoxical effect appears to be restricted to females. Evidence exists linking this sex difference to gonadal hormones and differential aspects of the central nervous system in the male and the female.

Using [18F]fluorodeoxyglucose and positron emission tomography (PET), the authors examined the regional brain glucose metabolism of six patients with chronic schizophrenia, six patients with chronic depression, and 12 normal control subjects. Three schizophrenic and four depressive patients had CAT scans that showed enlarged ventricles (ventricle-brain ratios higher than 9.0) and widened sylvian fissures. The PET scans of the schizophrenic and depressed patients did not differ significantly from those of the age-matched controls, and a previously reported metabolic "hypofrontality" was not confirmed. The patients with enlarged ventricles and widened sylvian fissures tended to have lower global metabolism.

Electrical activity from the amygdaloid nucleus in freely moving monkeys (Cercopithecus aethiops) during social interactions and alone were recorded via radiotelemetry. Spectral analysis of amygdaloid activity revealed highest power outputs occurred during behaviors related to sexual and aggressive interactions and the lowest with the tension-reducing behavior of grooming. Power output was not directly related to motor activity. These results suggest that amygdaloid activity is related to the emotional significance and degree of ambiguity of an interaction. It is hypothesized that at least two separate afferent systems, one for low frequencies and the other for fast frequencies, may be correlated with different behavioral events.

Members of Macaca speciosa have characteristics that make them suitable primates for neuropsychological investigation. They work well in discrimination training, have a varied behavioral repertoire and social interaction, and seem to be at least as intelligent as M. mulatta. They are docile and submit readily to laboratory routine.

Initiated social interactions of Macaca speciosa are decreased during the period of treatment with alpha-methyl-p-tyrosine, an inhibitor of catecholamine synthesis. The treated animals maintained stable body weights and appeared to be healthy. Similar depletion of indoleamines with p-chlorophenylalanine does not change these same observed behaviors in spite of weight loss, hair loss, ataxia, and debilitation in some of the animals.

Kittens sustaining bilateral amygdalectomy failed to show behavioral changes seen in the adult after subjection to similar lesions. No growth deficits or hypopituitarism occurred in the kittens. A certain level of neuroendocrine maturation may be necessary for the effects of amygdalectomy to be manifested.

Introduction Previous studies have shown that bilateral ablation of the amygdaloid nuclei and surrounding rhinencephalic structures in rodents, carnivores, and primates is uniquely characterized by a specific pattern of behavior. Animals sustaining such lesions exhibit behavior that is dominated by increased responsiveness to visual stimuli, hyperactivity, exaggerated oral activity, inability to recognize objects visually, loss of fear, and an increase in amount and diversity of sexual behavior. 6,14-16,18-21,24 Anatomical and electrophysiological studies of the amygdaloid nucleus and related structures have revealed efferent projections from the amygdala to widespread areas of the cortex and subcortex. 1,8-11 More specifically, the ventromedial nucleus of the hypothalamus appears to be a strong recipient of fibers arising from the amygdaloid complex. Electrolytic lesions of the ventromedial nucleus in cats and rats 2,12,23 have given rise to changes in behavior characterized by savage and aggressive attacks on other animals when approached, obesity, and hyposexual activity. In

Combined bilateral lesions of frontal granular cortex and caudate nucleus were produced in 7 monkeys between the 2nd and 56th postnatal day. When comparisons were made with 4 monkeys which had previously sustained bilateral resections of frontal granular cortex alone at comparable ages, it was found that the frontal-caudates, in contrast to the frontals, displayed failure to thrive, somato-motor and growth deficiencies, postoperative seizures and later cognitive impairments. When tested at the 7th postoperative month, 2 of the 3 surviving frontal-caudates could not perform a delayed response task beyond a minimal (0 sec) delay interval. It was concluded that early reflexive and somato-motor function is principally mediated by subcortical systems but that some degree of representation also exists at cortical levels. In contrast to neocortex, the caudate nucleus appears to be involved in a neural system responsible for the retention of delayed response capacity following early brain injury.

Lesions of the amygdaloid nuclei were made in male and female post weaning but prepuberal rats. The majority of the operated animals died within two weeks of extreme inanition following complete aphagia and adipsia. A group of these aphagic animals was maintained for five months by force feeding. In addition, a small number of operated animals showed no disturbances in feeding and grew quite normally without force feeding. All of the survivingaphagic animals also showed tooth spiralling and did not groom. Reproductive performance, up to the delivery of the young (as far as was tested adequately) was normal in the operated females whether aphagic or not. The aphagic males did not mate (in spite of ongoing spermatogenesis and normal testis and seminal vesicle weight) but this is most likely a secondary effect of inanition on mating behaviour, not a direct effect of the lesion. Operated non-aphagic males showed normal fertility. No behavioral hypersexuality was observed in any of the operated males, but a number of males showed spontaneous ejaculations in the presence or absence of females. One of the aphagic males was also an “ejaculator” as was also an obese rat with an isolated lesion of the ventromedial nuclei of the hypothalamus. Anterior pituitary function seemed normal in all of the operated rats whether aphagic or not.

Summary Twenty adult female rhesus monkeys (Macaca mulatta) were divided into 4 treatment groups of 5 subjects each; nonlesioned-nontrained (NLNT), nonlesioned-trained (NLT), lesioned-nontrained (LNT), and lesioned-trained (LT). All lesions were bilateral ablations of dorsolateral frontal cortex. The training consisted of color discrimination and delayed alternation. AChE activity was determined for 19 brain regions in each subject. Significant changes in AChE activity due to the lesion were found in orbital cortex, caudate nucleus and pons while training procedures produced significant changes only in the orbital cortex. The 3 brain areas in which significant AChE changes were found bear a close anatomical and functional relationship to the lesioned prefrontal cortex.

The eflect of uncinectomny on the social behavior of free-ranging rhesus monkeys was observed on Cayo Santiago Island. Operated subjects showed social indifjerence, failed to display appropriate aggressive and submissive gestures. were expelled from their social group, and evenitlually died. Two juvenile subjects with the lesion restricted to amygdala survived and have rejoinied their social group. Size of lesion and age at operation were major factors in determniting the degree of behavioral change.

Lesions of the rhinencephalon, primarily restricted to the amygdaloid complex, modify aggressive behavior of lynxes ( Lynx rufus), agoutis ( Dasyprocta agouti), monkeys ( Macacus rhesus) and domestic cats toward relative docility and precipitate a state of chronic hypersexuality. Relative docility was characterized by failure of the experimental animals to exhibit aggressive behavior, fear, or escape activity in the presence of threatening situations which precipitated such behavior in their preoperative periods. Hypersexuality was exhibited by marked increases in copulatory activity with males and females of their own and other animal species. It is concluded that the rhinencephalon and its diencephalic connections, in association with endocrine systems, are important regulators of emotional and sexual behavior of rodents, carnivores and primates.

The classic studies of Kluever and Bucy (1939), which by now have been reproduced repeatedly by many experimenters, have called attention to a syndrome of behavioral changes that occurs in the monkey after bilateral temporal lobectomy, or with lesion restricted to the amygdaloid nuclei. These changes can be briefly characterized as: 1) a decrease in belligerence and a reduction of fear toward normally fear-inducing objects including man; 2) a tendency to investigate orally and generally contact orally inedible objects including coprophagia and uriposia; 3) increased and inappropriate sexual behavior; 4) “hypermetamorphosis.”