Evolution of the Brain

How does those people who have Dissociative Identity Disorder fall into that? While rare, it isn't unknown. Would you consider that a type of memory disorder?

Hmm, I'm not sure. If you are asking my opinion I think it could be possible. Dissociative states are related to stress and trauma and we know that this alters the neurobiology of memory formation. I've never really thought about it, or researched it. I know a bit about PTSD, and it seems that the memory process is altered during the traumatic episode which can explain a lot of the symptomology.What I do know is that dissociative disorder is very controversial. I don't think there is much neuro work on it.Edited by melatonin, : No reason given.

I was wondering, since I know someone who has D.I.D. She is going through therapy , and has drastically improved over the last couple of years. From my observations, I will agree that there was alot of stress and trauma involved in her development of the condition, over a period of time.I would find it fascinating to see what kind of work on it was done beyond the therapy level.

Is this similar to a multiple personality disorder?

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Lucy

I am aware that our revered AdminQueztal warned us of topic drift when I first broached the subject of malaria and sickle cell anemia. I have also shown interest in the issues of serious mental disorders such as bipolar ad scizophrenia which only appear in the human population, not our nearest primates. So I suspect that these disorders are a product of a necessary devopment in the human brain. Is it possible, that our original non-human primates suffered a series of catastrophic events within their community which lead to the evolution of the human brain, and the consequence was, as we see with Tay Sacks and sickle cell anemia, the development of of too many of these genes leading to severe mental disorders. This is where my thinking lies.I have just come across a theory which was published in the Journal of Human Evolution. Having lived in Malaysia for many years and seen how monkeys respond to venemous snakes, I don't think her idea is sound, but would like an opinion from others, especially those who would have access to this Journal. Unfortunately, I can not give vol.# or date. The following is just a few lines from a report.While studying monkeys in Africa, Lynne Isbell, an anthropologist from the University of California stumbled hypothesis: The evolutionary development of the primate brain may have been significantly impacted by venomous snakes, which they learned to differentiate from otherswhich she published published in Journal of Human Evolution. Todd Preuss, a neuroscientist at Emory University, whilst beng cautious said the theory was audacious and showed a willingness to go beyond other scientific ideas.

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Lucy

It's the same thing. D.I.D. is what they currently call it. (new fad and all, just like manic depressive is now called bipolar)I will have to say that the more I observe of it,the more complex it is.

Melatonin,You very kindly gave me a link to a precis of a book which had been published in the journal "behavioral and brain sciences" including peer reviews. Unfortunately I could not access the following site you have provided:Free large file hosting. Send big files the easy way!Could you perhaps give me details such a title and author, and article reference in the journal. This should enable me to look for it in hard copy.Also can you, or perhaps someone else on this site. provide a reference (or actual details) as to how the human brain is defined as distinct from our closest primates.I was discussing this with an archaeologist who believes that proto-humans/humans emerged at different places - not out of the Rift Valley, Africa. What is your take on this?I assume that none here support the idea of a stochastic process, or series of, in the evolution of the human brain.

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Lucy

Hi there,Here's the journal reference. If you search for 'precis of principles of brain evolution' you may find it on a few sites.Précis of Principles of Brain Evolution
Georg F. Striedter
Behavioral and Brain Sciences, Volume 29, Issue 01, Mar 2006
doi: 10.1017/S0140525X06349011, Published online by Cambridge University Press 15 Mar 2006The human brain is disproportionately larger than other apes, so just absolute brain size alone would suffice, it's mainly neocortical. The convolutions are more extensive (particularly frontal lobe), but all the same gyri and sulci are present in other apes. More extensive connections are present between certain structures and there is greater hemispheric asymmetry. The article mentions some of this.But primates still make good animal models for behavioural neuroscience as the basic neural regions and functions are the same.Edited by melatonin, : No reason given.

Thank you, Melaton, I googled the article and obtained excellent data.

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Lucy

Another Query,From where, and what is the date for the oldest fossils of homo erectus?
I understand that Homo erectus pekinensis - Peking (Beijing) Man - was found at Zhoukoudian (Choukoutien) near Beijing (Peking), China. The finds have been dated from roughly 250,000-400,000 years ago in the Pleistocene.I believe that the oldest homo sapiens were from Africa c. 195,000 years ago.
http://www.sciencedaily.com/...ases/2005/02/050223122209.htm

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Lucy

In ancestor's tale, dawkins give a figure of around 1.8million years to 250,000yrs. Turkana Boy is dated approx 1.5million years.

I am on another site regarding dna, and have been informed that:"Each mutation in y dna that determines the haplogroup of a male is believed to have occurred only once and the sons of that male led to the members of that haplogroup and its subgroups. (The exact same thing occurred in the mtDNA of females.) There are major arguments over the geographical location of the birth of the first member of every grouping.”This was in response to a query I had posed regarding an article in Journal of Genetic Genealogy 1:12-33, 2005 A MOSAIC OF PEOPLE: THE JEWISH STORY AND A REASSESSMENT OF THE DNA EVIDENCE by Ellen Levy-Coffman. The particular question I raised was regarding the following passage."These UEPs represent a single historical mutational event, occurring only once in the course of human evolution."I had asked: Can you explain what she means by "a single historical mutational event, occurring only once in the course of human evolution" What actually was that event. when did it occur, and why only 'once' human evolution?”Can any of you very brilliant bods on EvC provide me with any information about this. I am looking at all possible avenues of the evolution of the human brain. I can’t accept the venemous snake hyphothesis by the anthropologist I mentioned in message #80.

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Lucy