It has been three years since I last posted on this blog. Those three years have been very active. In the 2010, with my good friend Jim Torbert, I founded the Atlantic Centre for Contemplative Scienc and Technology, a non-profit charitable organization in Halifax, Nova Scotia. The website is: http://accsat.org
The ACCSAT is dedicated to supporting and studying the application of contemplative concepts and practices in the institutions of secular society. To date we have forty faculty members, all of who are working in this field in one way or another.
My involvement with ACCSAT provides an opportunity to bring together the two main themes of my life work, mental disorder and contemplative practice.
A number of initiatives have arisen from the ACCSAT. In upcoming postings I will describe some of them. The most relevant for this blog is a series of workshop, entitled "Achieving a Sense of Mastery: Using mindfulness and contemplation to support recovery from mental disorder".
Overall, I hope this blog can provide one means of communication on the very inspiring and growing influence that meditation and contemplation are having in trying to address the current crisis in western societies.
Thanks for listening....dave
Wednesday, March 28, 2012
Wednesday, October 14, 2009
Western and Contemplative Sciences: a meeting with young neuroscientists
Earlier this week I was delighted, and honored, to sit in on a discussion with a small group of young neuroscientists. The topic was, “is the brain the mind; is the mind the brain?” They had gathered at the request of Dr. Dennis Phillips, a remarkably able and thoughtful professor at Dalhousie University. The conversation was held in a wonderful atmosphere of mutual respect in which all ideas expressed were considered and weighed in the light of existing evidence, theory and experience. There was an open minded, passionate interest in the topic, and all of its ramifications. The discussion roared on for nearly two hours, ending with an agreement to meet again soon, to continue on.
During the conversation I was struck with the parallels, often pointed out by the Dalai Lama, between western science and Buddhist psychology (what I would call contemplative science). Both ‘sciences’ involve gathering information and organizing it into a system of concepts that help us to better understand the nature of the world and of human experience. The goal is to get closer to ‘the truth’, to the way things actually are.
It’s interesting to consider that from this point of view there is no fundamental difference between spiritual (contemplative) and secular (scientific) intent.
Of course there are significant differences in methods. Contemplative science uses introspection (meditation) as the basic tool; individuals sit down and observe their own mind. From those experiences they develop concepts, and further refinements of the meditative techniques. These, in turn, are debated in a scholarly fashion, much like the ‘peer-review’ process in western science. Different ‘schools’ of thought arise and the entire enterprise moves forward, going through sequential ‘paradigm shifts’. (A concise description of this evolution in Buddhist thinking is available in the highly readable book, ‘Contemplating Reality’, by Andy Karr).
The young neuroscientists I met with were skeptical of introspection as a method, noting that it was inherently subjective and not amenable to the kind of ‘double-blind’ design that western science holds as an ideal. They also questioned whether the mind could actually observe itself; an interesting and useful point.
I suggested to them that contemplative science might, nonetheless, have something to offer to the current interest in correlating brain activity with mental experience (mind). It might be helpful, for example, to consider the various aspects or components of ‘mind’ that have been identified in the contemplative tradition as well as the concepts describing the overall structure and operation of mind.
In this regard, one view from contemplative science is that there is an ongoing, open ‘awareness’ that is continuous and that operates without conceptual or ‘dualistic’ thought. From this background of open awareness, suddenly arise the complex of thoughts and emotions with which we are so familiar, all based on a fundamental creation of the sense of self and other. Of particular interest is the view that the arising of thoughts and emotions occurs on a very short time scale, developing and elaborating over the course of perhaps 100 milliseconds and then dissolving back into the underlying open awareness. This arising occurs again and again, and yet again, so that it seems as if the thoughts and emotions are continuous. Yet, from the view of contemplative science, they are short duration, transitory phenomena; waves on the ocean of open awareness.
Is it this non-conceptual, open awareness that very experienced practitioners of meditation are able to access more consistently? Is this way of talking about the organization and function of ‘mind’ helpful in interpreting the current MRI and EEG studies of such practitioners?
It is no surprise that this two hour discussion did not lead to a definitive answer to the original question posed about the relationship of mind and brain. It was evident that there is no easy answer. Buddhist thought includes the concept of reincarnation, of some kind of continuation of mental experience after physical death. Most of the young neuroscientists preferred the idea that “mind is what the brain does”; that the brain produces mental experience. The end of brain function, in that view, is the end of mental experience. Importantly, this is the basis for determining the end of life in medical setting. If a person is ‘brain dead’, there is no further mental experience and the individual is ‘gone’.
Of course it is difficult to scientifically test this fundamental hypothesis; to do a double blind study. For the time being it seems each of us as western scientists or contemplative scientists (or both) will need to hold our own ‘working hypothesis’. Like a good Koan, the question of the relationship of brain and mind remains as a catalyst for sorting through our concepts and experiences and perhaps going beyond them to a more integrated understanding of our own mental experiences, so close at hand and yet so hard to fathom.
During the conversation I was struck with the parallels, often pointed out by the Dalai Lama, between western science and Buddhist psychology (what I would call contemplative science). Both ‘sciences’ involve gathering information and organizing it into a system of concepts that help us to better understand the nature of the world and of human experience. The goal is to get closer to ‘the truth’, to the way things actually are.
It’s interesting to consider that from this point of view there is no fundamental difference between spiritual (contemplative) and secular (scientific) intent.
Of course there are significant differences in methods. Contemplative science uses introspection (meditation) as the basic tool; individuals sit down and observe their own mind. From those experiences they develop concepts, and further refinements of the meditative techniques. These, in turn, are debated in a scholarly fashion, much like the ‘peer-review’ process in western science. Different ‘schools’ of thought arise and the entire enterprise moves forward, going through sequential ‘paradigm shifts’. (A concise description of this evolution in Buddhist thinking is available in the highly readable book, ‘Contemplating Reality’, by Andy Karr).
The young neuroscientists I met with were skeptical of introspection as a method, noting that it was inherently subjective and not amenable to the kind of ‘double-blind’ design that western science holds as an ideal. They also questioned whether the mind could actually observe itself; an interesting and useful point.
I suggested to them that contemplative science might, nonetheless, have something to offer to the current interest in correlating brain activity with mental experience (mind). It might be helpful, for example, to consider the various aspects or components of ‘mind’ that have been identified in the contemplative tradition as well as the concepts describing the overall structure and operation of mind.
In this regard, one view from contemplative science is that there is an ongoing, open ‘awareness’ that is continuous and that operates without conceptual or ‘dualistic’ thought. From this background of open awareness, suddenly arise the complex of thoughts and emotions with which we are so familiar, all based on a fundamental creation of the sense of self and other. Of particular interest is the view that the arising of thoughts and emotions occurs on a very short time scale, developing and elaborating over the course of perhaps 100 milliseconds and then dissolving back into the underlying open awareness. This arising occurs again and again, and yet again, so that it seems as if the thoughts and emotions are continuous. Yet, from the view of contemplative science, they are short duration, transitory phenomena; waves on the ocean of open awareness.
Is it this non-conceptual, open awareness that very experienced practitioners of meditation are able to access more consistently? Is this way of talking about the organization and function of ‘mind’ helpful in interpreting the current MRI and EEG studies of such practitioners?
It is no surprise that this two hour discussion did not lead to a definitive answer to the original question posed about the relationship of mind and brain. It was evident that there is no easy answer. Buddhist thought includes the concept of reincarnation, of some kind of continuation of mental experience after physical death. Most of the young neuroscientists preferred the idea that “mind is what the brain does”; that the brain produces mental experience. The end of brain function, in that view, is the end of mental experience. Importantly, this is the basis for determining the end of life in medical setting. If a person is ‘brain dead’, there is no further mental experience and the individual is ‘gone’.
Of course it is difficult to scientifically test this fundamental hypothesis; to do a double blind study. For the time being it seems each of us as western scientists or contemplative scientists (or both) will need to hold our own ‘working hypothesis’. Like a good Koan, the question of the relationship of brain and mind remains as a catalyst for sorting through our concepts and experiences and perhaps going beyond them to a more integrated understanding of our own mental experiences, so close at hand and yet so hard to fathom.
Friday, August 14, 2009
Summer time and the living is...hectic
Summer is supposed to be a time to relax. But it seems almost the opposite these days, atleast for me. My attention has been drawn away from this blog by other projects. But psychosis came back into focus yesterday when a friend called to talk about a long time mutual 'sister' who appears to have slipped, over the past year, into a serious psychosis with paranoid delusions and auditory hallucinations (hearing people talking about her).
Our 'sister' has a long history of psychological struggles along with difficulties in relationships. But her current mental state has clearly gone far beyond anything we've seen before.
Helping her has become problematic because she has incorporated her closest support people into her delusional system and now believes they are part of a massive conspiracy against her.
Of course she does not recognize the delusional nature of her beliefs and see no need for professional help. So, how to help her? One possible avenue is that she is involved with some social service agencies. Perhaps by making the professionals in that agency aware of the depths of her mental issues will prompt them to get her to someone who can do a proper assessment and determine if she is psychotic (which appears to be the case) and begin the process of treatment.
This situation is certainly not unique; something like it is playing out in many, many families in the midst of this summer season.
May those who need help receive it.
Our 'sister' has a long history of psychological struggles along with difficulties in relationships. But her current mental state has clearly gone far beyond anything we've seen before.
Helping her has become problematic because she has incorporated her closest support people into her delusional system and now believes they are part of a massive conspiracy against her.
Of course she does not recognize the delusional nature of her beliefs and see no need for professional help. So, how to help her? One possible avenue is that she is involved with some social service agencies. Perhaps by making the professionals in that agency aware of the depths of her mental issues will prompt them to get her to someone who can do a proper assessment and determine if she is psychotic (which appears to be the case) and begin the process of treatment.
This situation is certainly not unique; something like it is playing out in many, many families in the midst of this summer season.
May those who need help receive it.
Saturday, June 13, 2009
Response to Dennis
Dennis,
Thanks so much for your interesting comments. I very much appreciate our shared interest and look forward to learning from, and with, you.
Your comment that ‘imposing our preconceptions’ on sensory data should not imply intentionality to do so certainly makes sense to me. Experientially, I seem to be totally unaware of this process. I wouldn’t have a clue as to how to ‘impose my preconceptions’ even if I wanted to. It just seems to happen naturally. I can talk about it intellectually, but experientially it just seems to roll along on its own; which means that I rarely question the validity of my sensory experiences. In the same way, I suppose, most people who have hallucinations, like hearing voices, assume that their experiences are ‘real’.
Your other comment, about Jill Taylor’s experience during a severe stroke, raises the question (among others) of the process by which a sense of separate ‘self’ is generated. Again, this seems to be something that happens without intention, and on a moment to moment basis I, for one, take the result to be ‘real’ without even thinking about it.
Recently there have been a couple of papers from Dr. Patrick McGorry and his Early Psychosis group in Melbourne, suggesting that a disturbance in this sense of self is an early and core aspect of the development of psychosis. Here is their latest abstract:
A disturbed sense of self in the psychosis prodrome: linking phenomenology and neurobiology. Neurosci Biobehav Rev. 2009 Jun;33(6):807-17. Epub 2009 Jan 20.
Nelson B, Fornito A, Harrison BJ, Yücel M, Sass LA, Yung AR, Thompson A, Wood SJ, Pantelis C, McGorry PD .ORYGEN Youth Health Research Centre, Department of Psychiatry, The University of Melbourne, Victoria, Australia. nelsonb@unimelb.edu.au
Interest in the early phase of psychotic disorders has risen dramatically in recent years. Neurobiological investigations have focused specifically on identifying brain changes associated with the onset of psychosis. The link between these neurobiological findings and the complex phenomenology of the early psychosis period is not well understood. In this article, we re-cast some of these observations, primarily from neuroimaging studies, in the context of phenomenological models of "the self" and disturbance thereof in psychotic illness. Specifically, we argue that disturbance of the basic or minimal self ("ipseity"), as articulated in phenomenological literature, may be associated with abnormalities in midline cortical structures as observed in neuroimaging studies of pre-onset and early psychotic patients. These findings are discussed with regards to current ideas on the neural basis of self-referential mental activity, including the notion of a putative "default-mode" of brain function, and its relation to distinguishing between self- and other-generated stimuli. Further empirical work examining the relationship between neurobiological and phenomenological variables may be of value in identifying risk markers for psychosis onset.
Thanks so much for your interesting comments. I very much appreciate our shared interest and look forward to learning from, and with, you.
Your comment that ‘imposing our preconceptions’ on sensory data should not imply intentionality to do so certainly makes sense to me. Experientially, I seem to be totally unaware of this process. I wouldn’t have a clue as to how to ‘impose my preconceptions’ even if I wanted to. It just seems to happen naturally. I can talk about it intellectually, but experientially it just seems to roll along on its own; which means that I rarely question the validity of my sensory experiences. In the same way, I suppose, most people who have hallucinations, like hearing voices, assume that their experiences are ‘real’.
Your other comment, about Jill Taylor’s experience during a severe stroke, raises the question (among others) of the process by which a sense of separate ‘self’ is generated. Again, this seems to be something that happens without intention, and on a moment to moment basis I, for one, take the result to be ‘real’ without even thinking about it.
Recently there have been a couple of papers from Dr. Patrick McGorry and his Early Psychosis group in Melbourne, suggesting that a disturbance in this sense of self is an early and core aspect of the development of psychosis. Here is their latest abstract:
A disturbed sense of self in the psychosis prodrome: linking phenomenology and neurobiology. Neurosci Biobehav Rev. 2009 Jun;33(6):807-17. Epub 2009 Jan 20.
Nelson B, Fornito A, Harrison BJ, Yücel M, Sass LA, Yung AR, Thompson A, Wood SJ, Pantelis C, McGorry PD .ORYGEN Youth Health Research Centre, Department of Psychiatry, The University of Melbourne, Victoria, Australia. nelsonb@unimelb.edu.au
Interest in the early phase of psychotic disorders has risen dramatically in recent years. Neurobiological investigations have focused specifically on identifying brain changes associated with the onset of psychosis. The link between these neurobiological findings and the complex phenomenology of the early psychosis period is not well understood. In this article, we re-cast some of these observations, primarily from neuroimaging studies, in the context of phenomenological models of "the self" and disturbance thereof in psychotic illness. Specifically, we argue that disturbance of the basic or minimal self ("ipseity"), as articulated in phenomenological literature, may be associated with abnormalities in midline cortical structures as observed in neuroimaging studies of pre-onset and early psychotic patients. These findings are discussed with regards to current ideas on the neural basis of self-referential mental activity, including the notion of a putative "default-mode" of brain function, and its relation to distinguishing between self- and other-generated stimuli. Further empirical work examining the relationship between neurobiological and phenomenological variables may be of value in identifying risk markers for psychosis onset.
Sunday, June 7, 2009
On posting comments
It seems that some people are unable to post comments on this blog. If you are in that situation, please feel free to email your comments to me (davidwhitehorn@eastlink.ca) and I will post them for you.
Below are two interesting comments sent to me from Dennis P. I will respond to them in a day or so. Thanks Dennis.
Re: An Optical Illusion and Psychosis (April 21, 2009)
Hello David:
This is a fascinating observation, but I think that we have to be a bit careful in how we interpret it. Saying that we "impose our preconceptions" on the sensory data is cognitively loaded and carries a connotation of intentionality, while the processes at work may not be particularly cognitive at all. Our brains have encountered thousands (millions?) of examples of faces in our experience, including under conditions of degraded sensory input, prior to exposure to the stimulus evoking the illusion. The hollow mask stimulus confronts us with sensory data that are somewhat ambiguous, and most intelligent perceivers (man or machine) would probably default to the interpretation that has been helpful so many times before. I'm reminded of the case of relative motion. When a small object and a large object move relative to each other in the absence of other disambiguating information, the default interpretation is that it is the smaller object which is moving because the perceptual system has encountered that scenario far more often than the alternative. In both the "hollow mask" illusion and relative motion cases, we don't need to postulate that the perceptual system is attempting to "match our past experiences"; rather, the perceptual system uses past experience to provide the most likely interpretation of incoming, impoverished sensory data.
It remains fascinating that schizophrenics may not generally behave this way (at least with regard to the hollow mask illusion), and your point that our past experience influences our present perceptions is well taken. The point I'm trying to make here is that the mechanism through which experience expresses its effect may be much more low-level than the cognitive one that the expression "impose our preconceptions" implies. As I type this, it occurs to me that a low-level account of the hollow mask illusion might speak to the "salience" issue raised in your earlier posts: is the finding with the hollow mask illusion evidence that schizophrenics have an impaired ability to weight the data from the various sources of information (bottom-up, top-down) normally used in perceptual judgements? I hope that this helps. Kind wishes,
DPP
Re: Separating 'this' from 'that' (February 26, 2009)
Hello David:
I wonder how much of this "duality" is a natural consequence of the human gift of language? As soon as we apply the (linguistic) label "chair," everything else becomes "not chair." On the one hand, as you imply, this skill is what makes our interactions with others, and with the world, so workable. On the other hand, the labels create a duality that runs counter to the reality of the interdependence of all things, or "interbeing," to borrow the term from Thich Nhat Hanh. A quite striking case supporting this view is the work of Jill Bolte Taylor (see "My Stroke of Insight"; see also her talk at ted.com), the neuroscientist who suffered a left hemisphere stroke which, among other things, left her temporarily with a severe language impairment. In her book, Taylor describes her perceptions at the time of the accident, which I might in turn describe as "perception stripped of language." In this state, Taylor experienced a loss of boundary between self and other, and something of a dissolution of ego as hard, separate, and permanent; instead, everything, including perceptions, became fluid, with a distinct sense of "flow." This afforded Taylor a quite profound insight. It also rendered her interaction with her world almost unworkable.
Jill Bolte Taylor's retrospective descriptions of her stroke experience use a language (so to speak) that is a little different to that offered by meditation masters trying to teach us about absolute and relative truth. It seemed to me, however, that the descriptions have common themes, and this made me wonder if one of the insights provided by the disciplined meditative practice is to "see" past the language layer that we automatically impose on what would otherwise be more direct perceptions. Perhaps the real gift of being human is the ability to have a heartfelt appreciation of interdependence and impermanence, balanced with a language facility that enables us to communicate effectively with our world.
Thanks for your blog. Kind wishes,
Dennis PP
Below are two interesting comments sent to me from Dennis P. I will respond to them in a day or so. Thanks Dennis.
Re: An Optical Illusion and Psychosis (April 21, 2009)
Hello David:
This is a fascinating observation, but I think that we have to be a bit careful in how we interpret it. Saying that we "impose our preconceptions" on the sensory data is cognitively loaded and carries a connotation of intentionality, while the processes at work may not be particularly cognitive at all. Our brains have encountered thousands (millions?) of examples of faces in our experience, including under conditions of degraded sensory input, prior to exposure to the stimulus evoking the illusion. The hollow mask stimulus confronts us with sensory data that are somewhat ambiguous, and most intelligent perceivers (man or machine) would probably default to the interpretation that has been helpful so many times before. I'm reminded of the case of relative motion. When a small object and a large object move relative to each other in the absence of other disambiguating information, the default interpretation is that it is the smaller object which is moving because the perceptual system has encountered that scenario far more often than the alternative. In both the "hollow mask" illusion and relative motion cases, we don't need to postulate that the perceptual system is attempting to "match our past experiences"; rather, the perceptual system uses past experience to provide the most likely interpretation of incoming, impoverished sensory data.
It remains fascinating that schizophrenics may not generally behave this way (at least with regard to the hollow mask illusion), and your point that our past experience influences our present perceptions is well taken. The point I'm trying to make here is that the mechanism through which experience expresses its effect may be much more low-level than the cognitive one that the expression "impose our preconceptions" implies. As I type this, it occurs to me that a low-level account of the hollow mask illusion might speak to the "salience" issue raised in your earlier posts: is the finding with the hollow mask illusion evidence that schizophrenics have an impaired ability to weight the data from the various sources of information (bottom-up, top-down) normally used in perceptual judgements? I hope that this helps. Kind wishes,
DPP
Re: Separating 'this' from 'that' (February 26, 2009)
Hello David:
I wonder how much of this "duality" is a natural consequence of the human gift of language? As soon as we apply the (linguistic) label "chair," everything else becomes "not chair." On the one hand, as you imply, this skill is what makes our interactions with others, and with the world, so workable. On the other hand, the labels create a duality that runs counter to the reality of the interdependence of all things, or "interbeing," to borrow the term from Thich Nhat Hanh. A quite striking case supporting this view is the work of Jill Bolte Taylor (see "My Stroke of Insight"; see also her talk at ted.com), the neuroscientist who suffered a left hemisphere stroke which, among other things, left her temporarily with a severe language impairment. In her book, Taylor describes her perceptions at the time of the accident, which I might in turn describe as "perception stripped of language." In this state, Taylor experienced a loss of boundary between self and other, and something of a dissolution of ego as hard, separate, and permanent; instead, everything, including perceptions, became fluid, with a distinct sense of "flow." This afforded Taylor a quite profound insight. It also rendered her interaction with her world almost unworkable.
Jill Bolte Taylor's retrospective descriptions of her stroke experience use a language (so to speak) that is a little different to that offered by meditation masters trying to teach us about absolute and relative truth. It seemed to me, however, that the descriptions have common themes, and this made me wonder if one of the insights provided by the disciplined meditative practice is to "see" past the language layer that we automatically impose on what would otherwise be more direct perceptions. Perhaps the real gift of being human is the ability to have a heartfelt appreciation of interdependence and impermanence, balanced with a language facility that enables us to communicate effectively with our world.
Thanks for your blog. Kind wishes,
Dennis PP
Tuesday, April 21, 2009
An Optical Illusion and Psychosis
In an earlier posting we talked about the conclusion that the brain/mind creates our perceptions; an important insight that is accepted in western neuroscience and in eastern contemplative traditions.
Here is the link to the previous posting on this blog:
http://comingbacktoreality.blogspot.com/2009/01/constructing-reality.html
Optical illusions are an entertaining way to literally ‘see’ that what we see is not what is actually there. Instead, we tend to impose our preconceptions on the ‘data’ that has been presented to the brain by the sensory neurons and create perceptions that match our past experiences.
A posting on the website “Wired Science” provides an interesting example of such an optical illusion. The context is that in a recent research study people who had a diagnosis of schizophrenia actually were not able to see a particular optical illusion. They saw the visual object as it actually was while the ‘healthy controls’ experienced an optical illusion that fundamentally misinterpreted the actual visual object.
So, this is an interesting twist; people with psychosis see a visual object as it actually is, while people without psychosis are fooled.
The link to the Wired Science blog is as follows:
http://blog.wired.com/wiredscience/2009/04/schizoillusion.html
The optical illusion is demonstrated with a video that is available within the Wired Science blog.
Here is the link to the previous posting on this blog:
http://comingbacktoreality.blogspot.com/2009/01/constructing-reality.html
Optical illusions are an entertaining way to literally ‘see’ that what we see is not what is actually there. Instead, we tend to impose our preconceptions on the ‘data’ that has been presented to the brain by the sensory neurons and create perceptions that match our past experiences.
A posting on the website “Wired Science” provides an interesting example of such an optical illusion. The context is that in a recent research study people who had a diagnosis of schizophrenia actually were not able to see a particular optical illusion. They saw the visual object as it actually was while the ‘healthy controls’ experienced an optical illusion that fundamentally misinterpreted the actual visual object.
So, this is an interesting twist; people with psychosis see a visual object as it actually is, while people without psychosis are fooled.
The link to the Wired Science blog is as follows:
http://blog.wired.com/wiredscience/2009/04/schizoillusion.html
The optical illusion is demonstrated with a video that is available within the Wired Science blog.
Monday, April 20, 2009
The Dopamine Hypothesis, Version 3
The idea that psychosis involves hyperactivity of dopamine neurons has been generally accepted in psychiatry for nearly fifty years. A new review brings this hypothesis up to date. The authors (Howes and Kapur) incorporate results from a number of new techniques in molecular biology, genetics and brain imaging to define four major points.
Each of the points has interesting implications, some of which have already been mentioned in previous posting on this blog. For example, the first point in the review is that multiple factors, both genetic and environmental, interact, resulting in dopamine dysregulation. This point supports the idea we discussed that each person with psychosis has a unique path of causation and a unique condition. (Click below for the relevant previous posting on this blog).
http://comingbacktoreality.blogspot.com/2009/02/how-does-psychosis-arise-part-2.html
The second point is that the locus of the dopamine dysregulation is presynaptic, involving increased synthesis and tendency to release transmitter. The implication of this point is that current antipsychotic medications (which act postsynaptically) are acting ‘down stream’ from the point of actual dysregulation. Medications that act directly at the site of dysregulation may be preferable.
The third point is that dopamine dysregulation is linked specifically to the dimension ofpositive psychotic symptoms and 'psychosis proneness', regardless ofdiagnosis. This point is consistent with the idea that the current diagnostic system for psychotic disorders should be revised to emphasize symptom dimensions that are viewed as independent, each having its own particular underlying mechanisms. (Click below for the relevant previous posting on this blog).
http://comingbacktoreality.blogspot.com/2009/02/jim-van-os-and-salience-dysregulation.html
The fourth point is that dopamine dysregulation alters the appraisal of stimuli through the process of aberrant salience (stimuli that are not relevance are taken as relevant). This in turn leads to psychosis. This idea is extensively discussed in a previous posting on this blog; click below for that posting.
http://comingbacktoreality.blogspot.com/2009/01/salience-and-psychosis.html
Finally, there is no doubt much more to psychosis than dopamine. Still, the four major points in the updated hypothesis provide a helpful way to clarify issues in understanding psychosis.
Reference: OD Howes and S Kapur; The Dopamine Hypothesis of Schizophrenia:Version III - The Final Common Pathway. Schizophrenia Bulletin, March 2009.
Each of the points has interesting implications, some of which have already been mentioned in previous posting on this blog. For example, the first point in the review is that multiple factors, both genetic and environmental, interact, resulting in dopamine dysregulation. This point supports the idea we discussed that each person with psychosis has a unique path of causation and a unique condition. (Click below for the relevant previous posting on this blog).
http://comingbacktoreality.blogspot.com/2009/02/how-does-psychosis-arise-part-2.html
The second point is that the locus of the dopamine dysregulation is presynaptic, involving increased synthesis and tendency to release transmitter. The implication of this point is that current antipsychotic medications (which act postsynaptically) are acting ‘down stream’ from the point of actual dysregulation. Medications that act directly at the site of dysregulation may be preferable.
The third point is that dopamine dysregulation is linked specifically to the dimension ofpositive psychotic symptoms and 'psychosis proneness', regardless ofdiagnosis. This point is consistent with the idea that the current diagnostic system for psychotic disorders should be revised to emphasize symptom dimensions that are viewed as independent, each having its own particular underlying mechanisms. (Click below for the relevant previous posting on this blog).
http://comingbacktoreality.blogspot.com/2009/02/jim-van-os-and-salience-dysregulation.html
The fourth point is that dopamine dysregulation alters the appraisal of stimuli through the process of aberrant salience (stimuli that are not relevance are taken as relevant). This in turn leads to psychosis. This idea is extensively discussed in a previous posting on this blog; click below for that posting.
http://comingbacktoreality.blogspot.com/2009/01/salience-and-psychosis.html
Finally, there is no doubt much more to psychosis than dopamine. Still, the four major points in the updated hypothesis provide a helpful way to clarify issues in understanding psychosis.
Reference: OD Howes and S Kapur; The Dopamine Hypothesis of Schizophrenia:Version III - The Final Common Pathway. Schizophrenia Bulletin, March 2009.
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