The Medial Amygdala, Hormones, Pheromones, Social Behavior Network, and Mating Behavior

Whereas the adolescent brain is a major target for gonadal hormones, our understanding of hormonal influences on adolescent neural and behavioral development remains limited. These experiments investigated how variations in the timing of testosterone (T) exposure, relative to adolescence, alters the strength of steroid-sensitive neural circuits underlying social behavior in male Syrian hamsters. Experiment 1 simulated early, on-time, and late pubertal development by gonadectomizing males on postnatal d 10 and treating with SILASTIC brand T implants for 19 d before, during, or after adolescence. T treatment before or during, but not after, adolescence facilitated mating behavior in adulthood. In addition, preadolescent T treatments most effectively increased mating behavior overall, indicating that the timing of exposure to pubertal hormones contributes to individual differences in adult behavior. Experiment 2 examined the effects of preadolescent T treatment on behavior and brain regional volumes within the mating neural circuit of juvenile males (i.e. still preadolescent). Although preadolescent T treatment did not induce reproductive behavior in juvenile males, it did increase volumes of the bed nucleus of the stria terminalis, sexually dimorphic nucleus, posterodorsal medial amygdala, and posteroventral medial amygdala to adult-typical size. In contrast, juvenile anterodorsal medial amygdala and ventromedial hypothalamus volumes were not changed by preadolescent T treatment yet differed significantly in volume from adult controls, suggesting that further maturation of these brain regions during adolescence is required for the expression of male reproductive behavior. Thus, adolescent maturation of social behavior may involve both steroid-independent and -dependent processes, and adolescence marks the end of a postnatal period of sensitivity to steroid-dependent organization of the brain.

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Social Behavior Network

Encyclopedia of Neuroscience ◽

10.1007/978-3-540-29678-2_5487 ◽

2008 ◽

pp. 3755-3755

Keyword(s):

Social Behavior ◽

Behavior Network

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Dopaminergic neurons are preferentially responsive to advertisement calls and co-active with social behavior network nuclei in sneaker male midshipman fish

Brain Research ◽

10.1016/j.brainres.2018.09.014 ◽

2018 ◽

Vol 1701 ◽

pp. 177-188 ◽

Cited By ~ 3

Author(s):

Zachary N. Ghahramani ◽

Miky Timothy ◽

Joshua Varughese ◽

Joseph A. Sisneros ◽

Paul M. Forlano

Keyword(s):

Social Behavior ◽

Dopaminergic Neurons ◽

Advertisement Calls ◽

Behavior Network

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Maternal Separation Modifies the Activity of Social Processing Brain Nuclei Upon Social Novelty Exposure

Frontiers in Behavioral Neuroscience ◽

10.3389/fnbeh.2021.651263 ◽

2021 ◽

Vol 15 ◽

Author(s):

Sara Mejía-Chávez ◽

Arturo Venebra-Muñoz ◽

Fabio García-García ◽

Aleph Alejandro Corona-Morales ◽

Arturo Enrique Orozco-Vargas

Keyword(s):

Prefrontal Cortex ◽

Nucleus Accumbens ◽

Social Behavior ◽

Medial Prefrontal Cortex ◽

Paraventricular Nucleus ◽

Maternal Separation ◽

Lateral Septum ◽

Medial Amygdala ◽

Physiological Basis ◽

Brain Nuclei

Maternal separation has been shown to disrupt proper brain development and maturation, having profound consequences on the neuroendocrine systems in charge of the stress response, and has been shown to induce behavioral and cognitive abnormalities. At the behavioral level, maternal separation has been shown to increase offensive play-fighting in juvenile individuals and reduce social interest in adulthood. Since most of the studies that have evaluated the consequences of maternal separation on social behavior have focused on behavioral analysis, there is a need for a further understanding of the neuronal mechanisms underlying the changes in social behavior induced by maternal separation. Therefore, the aim of the present research was to assess the long-term effects of maternal separation on social interaction behavior and to assess the activity of several brain regions involved in the processing of social cues and reward upon social novelty exposure, using c-Fos immunohistochemistry as a marker of neuronal activity. Male Wistar rats were subjected to 4 h maternal separation during the neonatal period, 9:00 h–13:00 h from postnatal day 1 to 21, and exposed to social novelty during adulthood. After social novelty exposure, brains were fixed and coronal sections of the medial amygdala, lateral septum (LS), paraventricular nucleus of the hypothalamus, nucleus accumbens, and medial prefrontal cortex were obtained for c-Fos immunohistochemistry. Maternally separated rats spent less time investigating the novel peer, suggesting that maternal separation reduces social approach motivation. Furthermore, maternal separation reduced the number of c-Fos positive cells of the medial amygdala, paraventricular nucleus of the hypothalamus, LS, nucleus accumbens, and medial prefrontal cortex upon social novelty exposure. These findings suggest that maternal separation can reduce the plastic capacity of several brain nuclei, which constitute a physiological basis for the emergence of behavioral disorders presented later in life reported to be linked to early life adversity.

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Serotonergic activation during courtship and aggression in the brown anole,Anolis sagrei

PeerJ ◽

10.7717/peerj.3331 ◽

2017 ◽

Vol 5 ◽

pp. e3331 ◽

Cited By ~ 2

Author(s):

Jacob T. Hartline ◽

Alexandra N. Smith ◽

David Kabelik

Keyword(s):

Social Behavior ◽

Context Effects ◽

Early Gene ◽

Anolis Sagrei ◽

Functional Roles ◽

The Social ◽

Copulatory Courtship ◽

Brown Anole ◽

Behavior Network ◽

Reticular Nuclei

The role of serotonin (5-hydroxytryptamine, 5-HT) in social behavior regulation is not fully understood. While 5-HT release in nuclei of the social behavior network has generally been associated with inhibition of aggressive behavior across multiple classes of vertebrates, less is known about its effects on sexual, especially non-copulatory courtship display behaviors. Furthermore, most research has examined effects at 5-HT release sites, while studies examining the behavioral relevance of source cell populations have generated contradictory findings. This study utilized immunohistochemistry to examine the colocalization of 5-HT with Fos, an immediate early gene product and marker of neural activity, in the raphe and superior reticular nuclei of male brown anoles (Anolis sagrei) exposed to either aggression, courtship, or control social interactions. Supporting previous research, copulation was associated with a decrease in 5-HT activity, while a novel link between 5-HT activity and latency to non-copulatory courtship was also found. Within the aggression group, intensity and frequency of behavior were both associated with decreased 5-HT activity. An effect of social context was also seen, with anoles exposed to either courtship or aggression encounters showing decreased 5-HT activity in certain raphe and superior reticular nuclei populations compared to controls. Interestingly, context effects and behavioral effects were seen at separate brain nuclei, suggesting the presence of separate systems with distinct functional roles.

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