It is possible therefore to be learned to fear objects or contexts, and also it is possible to be learned not to fear them, it is related of complex way to other feelings (fear to the fear, fear to the love, fear to the death, fear to the ridiculous situation) and bears close relation to the different elements from the culture. For some, the fear in the human being, does not have any physiological relation (as reaction from alert), but it will be a product of the conscience, that expands our level of knowledge On the other hand, indicates to us, in an analysis on this subject, Elena Go’mez King (Monograph. Com), that Gray (1971) says: that it is considered to the fear, like a hypothetical state of the brain or neuroendocrino system, that arises in certain conditions and it is pronounced by certain forms of behavior. It emphasizes in addition, that in the development of the explanatory theories of the fear, are contributions of conductista psychology (Watson, 1924). In this theory, described as simplistic later, it is indicated that the innate atemorizantes stimuli, that is to say, those that we have not learned, but simply develop fear, due to their potential dangerous character for the individual, could be: the noise; the unexpected loss of support. and the pain. Also the etlogos with their knowledge and investigations, gave new perspective to the subject, thus Tinbergen in its book, " study of instinto". One talks about to the work carried out with Lorenz on threatening or dangerous silhouettes of birds, for the ducks and geese, trying to demonstrate and to illustrate the instinctive character of the behaviors of the fear. Really of the works of Tinbergen, it is possible to be deduced, with greater clarity, than a novel stimulus, in itself, produces fear. The works of the British etlogo Robert Hinde and those of Hartley (1954) if they got to try that in certain varieties of birds innate fears in front of predators exist, that express like behaviors of uproar or flight.