Neuroscience has long focused on the brain in terms of components: the visual cortex processes what we see, Broca’s area is the center for language, and so on. As our understanding of the brain has improved, however, it has become clear that a more accurate model depends on how these modules are wired together in circuits. A technique called diffusion tensor imaging (DTI) gives us a tool to probe the nature of those connections. A recent study suggests, for instance, that the more a person seeks out new experiences and relies on social approval, the stronger his or her wiring is among brain areas involved in reward, emotion and decision making.
Cognitive neuroscientist Michael Cohen and his colleagues at the University of Bonn in Germany asked 20 adults how often they sought out new experiences and relied on social approval. Then they used DTI to look at the subjects’ white matter, which connects disparate regions of the brain. Cognition and high-level processing happen in gray matter, found mostly in the outer layer of the brain and made up of the main cell bodies of neurons. White matter, on the other hand, is made up of the long, spindly “arms” of neurons, called axons, along which electrical signals travel. (This interior part of the brain looks white because the axons are sheathed in myelin, a white insulating protein that helps signals travel more quickly.)
Cohen’s team found that the more the subjects sought new experiences, the stronger their connections were from the hippocampus and amygdala, brain regions involved in decision making and emotion, to the ventral and mesial striatum, areas that process information related to emotion and reward. The scientists also found that the subjects who were most dependent on social approval had stronger than normal connections between the striatum and the prefrontal cortex, a brain area involved in higher-order decision making.
But what exactly do these connections of varying strengths mean? DTI, which maps white matter tracts by measuring water flow along them, is not yet easy to interpret: no one knows how exactly the strength or abundance of white matter connections correlates to the quality of neuronal communication. But studies using the technique have already uncovered white matter’s important role in health. Malfunctioning or damaged white matter can lead to multiple sclerosis, Alzheimer’s disease and epilepsy, and a study published last year suggested that pedophiles have less white matter connecting the brain regions involved in sexual arousal.
“Never before has it been possible to link cognition and behavior to the brain’s intrinsic wiring,” says Cohen, who now splits his time between the University of Amsterdam and the University of Arizona. “A better understanding of the brain’s communication network will lead to a better understanding of how the brain supports cognitive, emotional and social functions and, perhaps more important, why disconnections between parts of the brain might contribute to pathologies such as schizophrenia, autism and drug abuse.”
Note: This article was originally printed with the title, "Finding Connections".
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Add CommentFascinating! this fits closely to the personality model I have developed for managing teams in business
Reply | Report Abuse | Link to thisand my book MoodMapping that is coming out in the Autumn
Dr Liz Miller
You wish to read " REWIRING THE BRAIN" . Excerpts and contents on
Reply | Report Abuse | Link to thishttp://rewiringthebrain.net/
http://www2.xlibris.com/bookstore/bookdisplay.asp?bookid=39251
The problems facing the brain sciences generally concern how phenomenal experience is integrated and this of course concerns how the brain is structurally organized to function. Traditional approaches are accumulating a huge body of valuable information and yet the assembly of these diverse pieces of empirical data into a fully coherent picture still proves to be elusive. The traditional methodologies generally seek out causal connections from which researchers attempt to intuitively assemble a coherent theory with little else to go on but their own subjective speculations, which are admittedly better than nothing. However it is a bit like trying to assemble the pieces of a very complex jig saw puzzle without the picture on the cover of the box as a guide.
Reply | Report Abuse | Link to thisThere is a fascinating new way to delineate the structural dynamics of the cosmic order that begins with the dynamic picture on the cover of the box. It has never been explored before. It is not itself dependent upon language since it implicitly delineates the meaning inherent in all languages. It is not a theory of everything. It is a universal methodology that complements traditional approaches to physics as well as to the biological and social sciences. This is especially true of the brain sciences. It is fully consistent with empirical evidence in the public domain as well as phenomenal experience in the private domain. It embraces all possible structural possibilities to phenomenal experience in a way that provides direct intuitive insight into the dynamics of the creative process.
The basics of the methodology are briefly outlined in articles at www.cosmic-mindreach.com. There are a variety of articles on the website that apply the methodology to the sciences. It includes two articles on the human nervous system that are of special interest here. One deals with the meaningful integration of experience at the spinal level, synapse by synapse. Another deals with the meaningful integration of spinal, reticular, vestibular, proprioceptive and other sensory inputs with cerebral functions as mediated by the cerebellum for appropriate responses, synapse by synapse. The same methodology can be applied synapse by synapse to understand any number of interrelated neurological processes involved in decision making, since the human nervous system has evolved very precisely in this way. All the myriad cogs mesh because their structures are isomorphic.
Considerable patient reflection is required to attain a workable grasp of how the cosmic order works, then many doors begin to open. You may find that this new methodology can complement efforts to understand nervous system function in valuable ways. It can provide a living structural insight into the ongoing dynamics of the creative process at work in our own brain even as we remain a conscious participant.
Best wishes,
Robert Campbell
the hippocampus is very important - it does more than this - btw -
Reply | Report Abuse | Link to thisHere's what I just wrote on new imaging of the broca brain centers:
Reply | Report Abuse | Link to thisWow! This is incredible. Watching the speech centers of the brain works makes it possible to get a much deeper picture of the entire speech process and of how speech converts to sound and speech memories. The systems in the brain work in parallel to produce consciousness but human thought is mostly the product of the speech centers.
This means that we can track human thoughts from sensory awareness to their final changes in the brain for permanent memories. And it means we can watch memories being spoken about in the speech centers. This is the center for higher thought since verbal thought is only a human thing it is about time we were watching our speech centers do their thing to produce our basic 'talking to ourselves' that is the key to thought about the world. The senses store data and experiences but speech is what pulls it all together and allows us to generate new ideas about the world. The speech centers of the brain allow us to create a rich inner world that does not match up to the real world because of speech centers being able to construct new meaningful sentences that do not have to match up to the world around us- just be syntactically correct. Speech that is meaningful can easily be fully synthetic and not based on memories just syntactical deconstruction.
This is really cool stuff. Now that we can watch inner speech the old school philosophers have to admit that the real answers to what makes us human comes from the research labs and not from ancient, bad, really bad ideas about the world around us.
The brain systems work in parallel. This is what causes consciousness in animals and humans. Animals have very robust sensory systems which we have inherited as a species. But our thoughts about the world happen through self talk. The speech centers of the brain can easily create syntactically meaningful statements that do not have to be about the world around us. We can easily create entire universes with writing and human speech. Thoughts about the world are very hard to come up with because we have billions of thoughts about imaginary worlds which have never had an explanation before. But we can now watch as we think about the world around us now.
Human and animal consciousness is the result of the parallel operations of brains, human and animal. I created a general theory of information which I called patternism but it shows how nature builds information systems, including organic brains from the subatomic particles on out