Postencounter and circa-strike defensive contexts represent two adaptive responses to potential and imminent danger. In the context of a predator, the postencounter reflects the initial detection of the potential threat, whereas the circa-strike is associated with direct predatory attack. We used functional magnetic resonance imaging to investigate the neural organization of anticipation and avoidance of artificial predators with high or low probability of capturing the subject across analogous postencounter and circa-strike contexts of threat. Consistent with defense systems models, postencou

[Psychobiology of fear]. Fear is an affective experience and a normal psychobiologic reaction preparing the organism for defense or avoidance of threats. It is only abnormal when extent, expression and duration do not match the real danger. Three processes are elementary components of fear: 1. the perception of a signal for threat, 2. expectation, defined as inner mobilisation and augmented directional attention, 3. feeling arising from impending loss of control over the inner and outer milieu. Mutual dependence and interference between the three processes are often the basis for vicious circles in pathologic states of fear. Various aspects of fear, mainly of the anticipated fear can be explained by conditioned behaviour, a fact of significance not at last for rational psychotherapy. The form of expression and the extent of a reaction to fear is according to the hypothesis of Gray regulated by a complex functional central nervous system. The primary role of the latter consists in an inhibition of the actual behaviour in order to allow for alternative reactions adapted to the new circumstances.

Snakes have provided a serious threat to primates throughout evolution. Furthermore, bites by venomous snakes still cause significant morbidity and mortality in tropical regions of the world. According to the Snake Detection Theory (SDT Isbell, 2006; 2009), the vital need to detect camouflaged snakes provided strong evolutionary pressure to develop astute perceptual capacity in animals that were potential targets for snake attacks. We performed a series of behavioral tests that assessed snake detection under conditions that may have been critical for survival. We used spiders as the control st

withdraw tight against the groin when experiencing cold or fear . This may have provided an evolutionary advantage to our ancestors. The penis is a long, tube-like