Many species use chemical signals to convey information relevant to social and reproductive status between members of the same species (conspecific), but some chemical signals may also provide information to another species (heterospecific). Both of these types of complex chemical signals may be detected by the vomeronasal organ, which sends projections to the accessory olfactory bulb and on to...

The amygdala has been implicated in the processing of emotion and animacy information and to be responsive to novelty. However, the way in which these functions interact is poorly understood. Subjects (N = 30) viewed threatening or neutral images that could be either animate (facial expressions) or inanimate (objects) in the context of a dot probe task. The amygdala showed responses to both emo...

BACKGROUND Previous functional neuroimaging studies have demonstrated exaggerated amygdala responses and diminished medial prefrontal cortex responses during the symptomatic state in posttraumatic stress disorder (PTSD). OBJECTIVES To determine whether these abnormalities also occur in response to overtly presented affective stimuli unrelated to trauma; to examine the functional relationship ...

Background: Histological and in vivo MRI studies show that the amygdala is affected by Alzheimer’s Disease (AD) pathology; its shape is altered [1,2] especially in its medial aspect [3]. Aim: To assess in vivo local amygdalar changes in AD patients using high resolution MRI at 3 Tesla, and identify the involved nuclei. Methods: 19 AD patients (age 76±6 years, Mini Mental State Examination (MMSE...

Projections from the posterior thalamus to the amygdala have been implicated in the processing of the emotional significance of acoustic stimuli. The aim of the present studies was to determine which areas of the amygdala receive afferents from posterior thalamic structures that, in turn, receive afferents (presumably acoustic afferents) from the inferior colliculus. Projections from the poster...

Abnormalities of the medial temporal lobe have been consistently demonstrated in schizophrenia. A common functional polymorphism, Val108/158Met, in the putative schizophrenia susceptibility gene, catechol-O-methyltransferase (COMT), has been shown to influence medial temporal lobe function. However, the effects of this polymorphism on volumes of medial temporal lobe structures, particularly in ...

Neurobiological studies demonstrate the amygdala’s role in emotional memory, and psychological studies suggest a particular pattern: enhanced memory for the gist but not the details of complex stimuli. We hypothesized that these two findings are related. Whereas normal (n 5 52) and brain-damaged (n 5 22) controls showed the expected enhancement of gist memory when the encoding context was emoti...

Neurobiological studies demonstrate the amygdala’s role in emotional memory, and psychological studies suggest a particular pattern: enhanced memory for the gist but not the details of complex stimuli. We hypothesized that these two findings are related. Whereas normal (n 5 52) and brain-damaged (n 5 22) controls showed the expected enhancement of gist memory when the encoding context was emoti...

Previous data have consistently demonstrated an inhibitory effect of androgens on stressinduced hypothalamic-pituitary-adrenal (HPA) responses. Several brain regions may influence androgen-mediated inhibition of the HPA axis, including the medial preoptic area. To test the role of the medial preoptic nucleus (MPN) specifically, we examined in highand low-testosterone replaced gonadectomized rat...

Introduction: Aggressive behavior is a major issue in the field of mental health. Pharmacotherapy is often used for the treatment of violent individuals. A neurochemical system most consistently linked with aggression is the GABAergic system. The aim of the present investigation was to examine the effect of muscimol (GABAA agonist) 250 and 500 ng/rat and picrotoxin (GABAA antagonist) 1.5 and...