Posts published during January, 2009
January 29, 2009 by Cara Flanagan.
We recently received the question above from Claire Matthews of The Castle School in Bristol and thought some of you would be interested in the answer: The SAM system concerns the adrenal medulla and the release of adrenaline/noradrenaline which has the effect of creating physiological (sympathetic) arousal and producing the fight or flight response. The HPA access concerns the adrenal cortex which produces corticosteroids such as cortisol, which help the body to recover after stress but also have negative effects e.g. reduced immune function. Now to the question – do they happen simultaneously or does the SAM system come first and the HPA second?
The answer is both. Essentially both systems are triggered by a stressor but one (SAM) is an instantaneous response like lighting a match, whereas the other (HPA) is much slower and doesn’t happen very easily (like lighting a fire). It is harder to achieve (needs a continuing stressor) and is only activated in more extreme circumstances. So in a sense the HPA response does come second because, even though it is triggered at the same time as the SAM, its response is seen some time later – well after the fight/flight response.
January 26, 2009 by Evie Bentley.
Serotonin is involved in many behaviours, and new research suggests that a mutation in a gene that transports the brain chemical serotonin could influence our social behaviour.
This is based on American research using rhesus macaque monkeys because they are the only other primates with a particular genetic trait. Usually we are homozygous for this emotion-regulating serotonin transporter gene, having either two long (L/L) or two short (S/S) versions. But previous research has shown that there are a few people - more common in those of Asian descent – who are heterozygous and have social anxiety and similar behaviours. Rhesus macaque monkeys are the only other primates with this genetic trait. The research showed that those with the S/L version spent less time looking directly at the faces and eyes of other monkeys, and were less likely to want to look at a picture of a high-status male monkey, and also were less likely to be risk takers, than those who were homozygous.
Platt says, “For both human and non-human primates, faces and eyes are a rich source of social information, and it’s well-established that both humans and macaques tend to direct visual attention to faces, especially the eye region. Rhesus monkeys live in highly despotic societies and convey social rank information by making threats and showing dominant and submissive behaviors.”
The findings could give researchers a new model to help in studying social anxiety, and perhaps more serious disorders such as autism and schizophrenia.
According to Watson, “Altogether, our data show that genetic variation in serotonin function does contribute to social reward and punishment in macaques, and thus shapes social behavior in both humans and rhesus macaques. This study confirms rhesus monkeys can serve as a model of what goes on in our brains, even in the case of social behavior.”
How similar are we to primates such as rhesus monkeys?
What are the arguments fordoing psychological research on animals such as these, and what are the arguments against this?
The answers to the questions from Chapter 4 (stress) are now available! Chapter 5 coming soon! You can find these answers by clicking on the ‘book resources’ tab – along with other useful things.
January 15, 2009 by Cara Flanagan.
Just a quick evaluation nugget for you. Fraley and Spieker (2003) have found that classifying infants by type may not be accurate. The researchers looked at data recorded for over 1000 children involved in the NICHD study. The data had been collected from observations made in the strange situation. The re-analysis showed that variations in patterns was largely continuous i.e. children didn’t possess a cluster of characteristics typical of one particular category. Instead they differed along various dimensions such as response to mother’s return.This challenges any research which has categorised children as secure, insecure-resistant or insecure-avoidant because such exclusive categories don’t represent reality, according to this research. Fraley, R. C., & Spieker, S. J. (2003). Are infant attachment patterns continuously or categorically distributed? A taxometric analysis of strange situation behavior. Developmental Psychology, 39, 387-404.
In the summaries at the end of chapter 2 (page 58), the text regarding the weaknesses of learning theory says that ‘Schaffer and Emerson (1964) found infants were most attached to the adult who fed them’. This is wrong, as the text earlier in the chapter states that they found that infants were not necessarily most attached to the person that fed them – a more important factor in the development of attachment was the responsiveness of the adult (see page 35).
