EP's and EZ's eval Flashcards
S endogenous: research support (morgan) + ELAB: animal studies
ID: a strength of endogenous pacemakers is that they have research support
Q: this means that the importance of the SCN has been demonstrated in research.
EX: for example, morgan (1955) bred hamsters so that they had circadian rhythms of 20 hours rather than 24. SCN neurons from these abnormal hamsters were transplanted into the brains of normal hamsters, which subsequently displayed the same abnormal circadian rhythm of 20 hours, showing that the transplanted SCN had imposed its pattern onto the hamsters.
AN: therefore, this research demonstrates the significance of the SCN and how endogenous pacemakers are important for biological circadian rhythms.
ELAB: however, this research is flawed because of its use of hamsters. humans would respond very differently to manipulations of their biological rhythms, not only because we are different biologically, but also because of the vast differences between environmental contexts. this makes research carried out on other animals unable to explain the role of endogenous pacemakers in the biological processes of humans.
S exogenous: research support (siffre)
ID: furthermore, a strength of exogenous pacemakers is that there is research evidence to support
Q: research has been conducted to investigate circadian rhythms and the effect of external cues like light on this system.
EX: for example, siffre (1975) found that the absence of external cues significantly altered his circadian rhythm. when he returned from an underground stay with no clocks or light, he believed the date to be a month earlier than it was.
AN: this suggests that his 24-hour sleep-wake cycle was increased by the lack of external cues, making him believe one day was longer than it was, and leading to his thinking that fewer days had passed. demonstrating the importance of exogenous pacemakers
W: biologically reductionist
ID: however, the explanation for endogenous pacemakers and exogenous zeitgeibers can be criticised for being biologically reductionist
Q: this means that despite all the research support for the role of endogenous pacemakers and exogenous zeitgebers, it could be criticised for an over-emphasis on biological factors
EX: for example, the behaviourist approach would suggest that bodily rhythms are influenced by other people and social norms, i.e. sleep occurs when it is dark because that is the social norm and it wouldn’t be socially acceptable for a person to conduct their daily routines during the night.
AN: therefore, the research discussed here could be criticised for being reductionist as it only considers a singular biological mechanism and fails to consider the other widely divergent viewpoints.
