It is argued that biorhythms such as the release of hormones from the pituitary gland, the daily rise and fall in body temperature and the sleep wake cycle are underpinned by some form of body clock determined somewhere in the brain. Psychologists have been attempting to agree upon the extent to which this clock should be seen as a free running mechanism or one which is entrained and regulated by factors such as shadowy and dark and others exogenous zeitgebers or time givers such as social routines of others and man-made clocks.
It is thought that one of the bodys most important clocks might be situated in the suprachiasmatic nucleus (SCN), a tiny cluster of eye cells located within the hypothalamus. This SCN is tie-uped to the optic nerve by a thin tuft of nerve fibres which breaks off merely above the optic chiasm and this provides a direct link with light levels in the extracurricular world. This is important as it provides small evidence that the body clock is regulated by the external world.
It is likely that this structure is able to generate its own circadian rhythm through the process of protein synthesis, when a certain utmost threshold is met, protein synthesis will be inhibited and when levels choke low enough this process will be reactivated as the minimum threshold has been reached. This suggests that the clock could run without influence from the outside world.
This is supported by Morgan (1995) who investigated the role of endogenous pacemakers, in special the SCN, in the circadian rhythms of hamsters. Morgan removed the SCN in hamsters and found that their circadian rhythm disappeared. However, when the SCN was replaced by those of foetal hamsters, the circadian rhythm was re-established.
some(prenominal) people may argue that it is unethical to use hamsters as they cannot give fully informed consent to the procedure. In addition, lesions were created in their brain in order to remove...If you want to get a full essay, order it on our website: Orderessay
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