Posts tagged Brain
I recently came across an authors@google talk by Rick Hanson, who is the author of ‘Buddha‘s Brain: the practical neuroscience of happiness, love and wisdom’ and was immediately drawn by the similarity of the framework he uses and my ABCD model. Rick draws a lot from the Buddhist tradition and its humbling to find many similarities between what buddha preached thousands of years ago and what neuroscience tell us today.
In particular the root cause of suffering is believed to be due to
1) trying to avoid unescapable threats/ pains etc like ageing and death.
2) pursuit of pleasures/opportunities etc that are fleeting in nature/ not permanent.
3) trying to separate from and become individuated while the nature of reality is connected and interdependent.
4) trying to stabilize that which keeps on changing
The roots of these Rick believes are tied up to the three (I’ve extended them to 4) motivational systems that govern us. These are:
1) Avoid system – reigning this in leads to Calm , a sense of peace and increase in a feeling of moment-to-moment Happiness.
2) Approach system - properly aligning this leads to Contentment, a sense of gratitude and increase in feelings of Well-being.
3) Attach system – properly utilizing this leads to Caring, a sense of loving-kindness and increase in feelings of Love.
4) Absorb system – properly using this leads to Creativity, a sense of insight and increase in feelings of Wisdom.
To me these are absolutely aligned to the ABCD model; the Avoid system is primarily about reacting to -ve (or even +ve ) Affect; Approach system is driven by how Behaviouraly actively or passively you respond to opportunities; the Attach system is all about the dynamics driving the Self-other relational issues; while the Absorb system is the more Cognitively focussed one driven by broad / narrow focus concerns.
Rick also thinks that these are related to how the learning (synaptic strength modification) , regulation (inhibition or excitation due to firing) and selection (the decision to fire based on summation of inputs) happens in brains at synapse levels and that reigning these systems leads to Mindfulness (attention relevant/leading to learning) , Virtue (self-regulation of behaviour) and Wisdom (the ability to make informed choices) at the macro level. As Rick believes that not only brains lead to minds, but what and how our minds act also affects our neural wiring due to self-directed neuroplasticity, he advocates practising mindfulness, virtue and wisdom to rewire your brain to take it to the Buddha’s state.
Here one might pause and consider what mind actually is. some would equate it simply as mind is what the brain does, but more reflection shows that mind is multidimensional (ya…. fits the ABCD model). To me, mind is a result of:
1) Brain Activity
2) Body rootedness (embodied cognition)
3) Embedded with Other minds (relational construct)
4) Shaped/interpreted by culture
Another thing to note about Rick is that he is a fan of Paul Mc lean’s tripartite brain; extending both the MacLean model and Rick associations and aligning with ABCD model, I see the evolution of brain as:
1) Brain-stem (Reptilian brain) : the relative brain sizes in reptiles or those driven by this Avoid mode system should be proportional to their land areas that they need to defend as in territorial defence; this is what I predict, the greater the area/ territory they typically defend the bigger this area. In the reptilian evolution this factor must have driven brain evolution.
2) sub-cortical areas ( Paleomammilian brain) : the relative size of brain in these simple mammals should be tied to their foraging area or how vastly they explore for food/ mating opportunities. I predict that brain evolution during this phase was tied to the Approach mode and linked with exploration propensity and must be linked with typical foraging area, with animals foraging far and wide having bigger brains proportional to those who don’t.
3) cortical areas ( mammalian brain ) : the relative size of brain in these higher mammals corresponds with the social group size (the famous Dunbar number) . This phase of brain evolution was primarily driven by Attach motivational system where concerns for others and groups drove evolution of brain with those having dense social groups needing more brainpower.
4) Neocortical areas/ lateralizations (the human/primate brain): the relative size of brains might be related to artistic/ imaginative ability. This phase of brain evolution is still taking place and is being primarily driven by Absorb system; how much one assimilates and accommodates and how much one intellectually rejects would determine whether the brain evolves further and proportional to how creative (broad-minded) the species is. The more narrow minded/ unimaginative the lesser thee neo-cortical size; perhaps this is the advantage we had over Neanderthals and other hominids. The autism-schizophrenia continuum may be one effect of the cognitive evolution still happening.
Which brings me maenderingly to my final comparison:
2) Behaviour or Approach system deregulation leads to Addiction. The neurotransmitter of concern here is Dopamine. Compare also to cloningers Novelty Seeking
3) Drive/Dynamics or Attach system deregulation leads to Bipolar or manic depression. The neurotransmitter of concern may turn out to be norepinephrine. Compare to cloningers Reward Dependence.
4) Cognition or Absorb system deregulation leads to Schizophrenia . The neurotransmitter of concern may turn out to be acetylcholine.
That covers the major group of disorders. I’m still reading ‘Buddha’s brain’ and not all insights shared above are related to what Rick/ Buddhism says; but I find them broadly aligned with my ABCD model and the eight stage evo-devo model based around Theodore Millons four basic polarities.
Autism is a spectrum disorder , better referred to as ASD, It has been known for some time that differences like autism are, multi-dimensional and not readily reducible to a single set of mechanisms or genetic causes. In the past we have discussed how the disorder may be related to structural differences in the brain like those due to minicolumnar differences.
A new study looked at structural differences in brains of people (adults) with ASD and instead of focusing piece-meal on one feature (like minicolumns) combined a multitude of structural features and used a multi-dimensional classification system to determine the accuracy and specificity of the structural differences to predict/aid in diagnoses.
They came uyp with five dimensions- two based on volumetric measurements (surface area and cortical thickness) and the other three on geometric features (average convexity/concavity, mean radial curvature and metric distortion. (the article is open access, so go read it to find what these mean:-) )
What they found was that cortical thickness was the strongest predictor and that predictive power was greater for Left hemisphere measures than for right hemisphere measures.
They also talk about what these measures may mean in terms of underlying neurons and substructures and I reproduce that here:
There is already evidence to suggest that several aspects of cerebral morphology are different in people with ASD—including both volumetric (i.e., cortical thickness, regional area) and geometric (i.e., cortical shape) features (Levitt et al., 2003; Nordahl et al., 2007); and that different morphological features may have different neuropathological and genetic underpinnings (Panizzon et al., 2009). For instance, cortical thickness is likely to reflect dendritic arborization (Huttenlocher, 1990), while cortical surface area has been linked to the number of minicolumns in the cortical layer (Rakic, 1988). Geometric features such as cortical folding pattern, on the other hand, may reflect an abnormal pattern of intrinsic as well as extrinsic connectivity (Van Essen, 1997). Thus, examining the relationship between such multiple cortical features could provide invaluable insights into the multifactorial etiology of ASD.
We know form previous work that all of the above (arborization, minicolumns, local and global connectivity) have been implicated in Autism. The important take-home for me from thi sstudy is the fact that all these are governed by possibly separate underlying genetic mechanisms and may thus be independent of each other. On its own variations in one dimension may not lead to full blown autism, but when variations in all five or more dimensions combine they may make one more susceptible to ASD diagnosis.
Remember we are only talking about structural change sin brains here; we haven’t even touched upon functional differences (default mode network?) and there is plethora of evidence that functional changes are also very important. Overall I believe the multi-dimensional nature of underlying structural and functional differences lend autism the spectrum property and also a continuum with normality. As always I would be eager to know how the SVM they used to classify Autistics fared when asked to classify Psychotics …did the pattern they see was reverse of Autism and inline with the Schizophrenia/psychosis as opposed to Autism theory?
Ecker, C., Marquand, A., Mourao-Miranda, J., Johnston, P., Daly, E., Brammer, M., Maltezos, S., Murphy, C., Robertson, D., Williams, S., & Murphy, D. (2010). Describing the Brain in Autism in Five Dimensions–Magnetic Resonance Imaging-Assisted Diagnosis of Autism Spectrum Disorder Using a Multiparameter Classification Approach Journal of Neuroscience, 30 (32), 10612-10623 DOI: 10.1523/JNEUROSCI.5413-09.2010
Answer this honestly:
1. Do you feel preoccupied with the encephalon (think about previous editions or anticipate next edition)?
2. Do you feel the need to read the encephalon with increasing number of contributions in order to achieve satisfaction?
3. Have you repeatedly made unsuccessful efforts to control, cut back, or stop reading encephalon?
4. Do you feel restless, moody, depressed, or irritable when attempting to cut down or stop reading encephalon?
5. Do you end up reading encephalon longer than originally intended?
6. Have you jeopardized or risked the loss of significant blog posts, twitter conversations , web surfing opportunity because of the encephalon?
7. Have you lied to family members, therapist, or others to conceal the extent of involvement with the encephalon?
8. Do you use the enecpahlon as a way of escaping from research or of relieving a writers block (e.g., feelings of helplessness, guilt, anxiety, depression (over not being able to write/contribute)?
Answering “yes” to five or more questions may mean you suffer from encephalon addiction over a six month period and when not better accounted for by a manic episode or internet addiction. Contact Sandeep Gautam to get institutionalized:-) The formal diagnostic guidelines coming soon to a DSM-V near you!
The stage for the year end edition is set by this post from the Neurcortic that asks and concludes in the negative that whether internet addiction shrinks the brain? The writeup nicely sums up the divergent views on internet addiction from those of Kimberly Young at one end to Vaughan Bell of Mind Hacks fame at the other. No points for guessing where my or Neurocritic’s sympathy lies:-)
Now that you have read my ill-styled post till here, I am sure you love to inflict pain on yourself- else why bother continue reading. Perhaps you are masochistic; or perhaps you are not- you are just a borderline who doesn’t feel any pain-whether real or imagined. the second contribution from Neurocritic looks at recent research that found low activation in pain perception and assessment regions of the brain for borderline subjects, who typically self-injure, while they were imaging themselves under self-injury condition.
Do you like reading encepahlon (a light and sweet candy to your eyes I am sure) or the regular mouse trap posts (some spinach that is hard to eat and takes longer to digest) . Does you decision as to whether to prefer candy in childhood, affect your life outcomes like how violent you may turn out in adulthood? this is the question BrainBlogger grapples with in this post that looks at why sugar and spice is not always nice and children eating a lot of candy can become violent later on. One reason could be lack of ability to make wise delayed gratification decisions just like in the marshmallow study.
Ok. now for some cool experimentation.stop and take a deep breath. Some of you Imagine reading the encephalon. Others go ahead and read it. now look at encephalon logo. some of you look at it twice. some thrice. now tell me, and the answer from all of you should be in the affirmative,- as to whether you read the encephalon or just imagined reading it. In a study very similar to this, but spread over weeks, it was found that when imagining an activity and subsequently(after a week or so) being presented with pictures showing the completion of the activity, the subjects were more likely to confound , at a later date, that they had actually indulged in the activity and not just imagined it. such is the power of words and this is amply highlighted by NeuroNarrative coverage of the same in which he also extends this to everyday settings including eye-witness testimonies.
Just like images are so important, words too are- they can literally break your heart. The second contribution from NeuroNarrative looks at how a predominance of emotional words as opposed to cognitive words in a couples’ arguments can signify heart risks, risks of diabetes etc. via the stress hormones mechanism. That reminds me, that to unbreak your heart (a la Toni Braxton), perhaps we also need a study of how compassionate and empathetic words used in conversations can literally heal the heart and raise immunity etc.
Talking about enhancing cognitive fitness, how can one but miss the leaders in the field – the SharpBrains. This time SharpBrains lists other leaders and 10 innovations ranging from computerized CBT to ‘cognitive shops’ that are defining the field and raising hopes for the ageing population.I am sure reading encephaoln on a regular basis is another sufficiently demanding and cognitive fitness enhancing innovation that Mo had originally come up with, that I have mentioned Neurophilosophy in this encephalon (despite no submissions) by the founding father.
Does the idea of a tongue -in cheek encephalon resonate with you? Does it set your brain neurons and circuits and systems all in synchrony, resonating with each other- if so you may also like this post by Modern Dragons, that argues that neural resonance and neuroacoustics may be the one holy grail principle of neuroscience that people may have overlooked and that might explain everything.
Talking about grand unifying theories, I cannot but help self plug my post on the recent Crespi et al findings that vindicated my grand theory of Autism and Psychosis as opposites on a continuum. The post itself is a shameless chest thumping and self-congratulating piece of basking in reflected glory. If you are still not convinced that I eat , breathe and drink the autism-psychosis theory, watch this devidutt patnaik TED talk (my second contribution) and see how craftily I can relate almost anything to my pet theory:-)
That is it folks. 2009 is gone and we will see a brand new, non-addictive version of encepahlon in 2010 soon. Till then keep reading and reading this edition -its not just sweet and good for your ageing brains, its nicely worded , has good pictures and is the perfect place for contemplating grand unifying theories, even if they cause you discomfort- I know all of you are borderlines and either love or are insensitive to this self inflicted pain!
The Mouse Trap will be hosting Encephalon, the premier brain and mind carnival for all things related to psychology/neuosceince on 7th December i.e. upcoming Monday. Do send in your submissions to encephalon[DOT]host[AT]gmail[DOT]com or directly to me using contact form/mail to editor[AT]the-mouse-trap[DOT]com.
Looking forward to your rocking submissions to make a memorable 2009 year-end encephalon carnival that takes a retrospective look at the year gone by!
I came across this study article today by Farb et al, that talks about two distinct neural networks in the brain that are involved in self-reference. To be fair, the networks are somewhat blurred and overlap in naive people, while in people who practice mindfulness meditation, the networks are more distinct and non-overlapping. My interest was piqued as I am a keen follower of default-brain network , which has been implicated in self-referential thinking and this article seems to at one point argue that the narrative self viz ‘me’ is grounded in default brain network, while the experiencer ‘I” has some other nearby related areas as the neural substrates.
But first let us clarify what we mean by ‘me’ and ‘I’. For this I would like to quote form a Gallagher article:
Ever since William James (1890) provided a catalogue of different senses of the self, philosophers and psychologists have been hard at work refining and expanding the possible variations of this concept. Supplementing James’ inventory of physical self, mental self, spiritual self, and the ego, Neisser (1988), for example, suggested important distinctions between ecological, interpersonal, extended, private, and conceptual aspects of self. More recently, reviewing a contentious collection of essays from various disciplines, Strawson (1999) found an overabundance of delineations between cognitive, embodied, fictional, and narrative selves, among others. It would be impossible to review all of these diverse notions of self in this short paper, so I have focused on several recently developed approaches that promise the best exchange between philosophy of mind and the other cognitive sciences. Because these approaches move in divergent theoretical directions they should help to convey the breadth of philosophical analysis on this topic. They can be divided into two groups that are focused, respectively, on two important aspects of self.
A first approach involves various attempts to account for a ‘minimal’ sense of self. If we strip away all of the unessential features of self, the intuition is that there is a basic, immediate, or primitive something that we are still willing to call a self. This approach leaves aside questions about the degree to which the self is extended beyond the short-term or ‘specious’ present to include past thoughts and actions. Although identity over time is a major issue in the philosophical definition of personal identity, the concept of the minimal self is limited to that which is accessible to immediate and present self-consciousness. Non-philosophers have found that certain aspects of the minimal self are relevant to current research in robotics. Furthermore, aspects of the minimal self that involve senses of ownership and agency in the context of both motor action and cognition can be clarified by neurocognitive models (developed to explain pathologies such as schizophrenia) that suggest the involvement of specific brain systems (including prefrontal cortex, SMA, and cerebellum).
A second approach involves conceiving of the self in terms of narrative, a concept imported into the cognitive-science context by Dennett (1991) , but one which may have a more complex significance than indicated in Dennett’s account. The narrative self is extended in time to include memories of the past and intentions toward the future. It is what Neisser refers to as the extended self, and what Dennett calls a ‘nonminimal selfy’ self. Neuropsychological accounts of episodic memory or loss of memory can help to circumscribe the neurological underpinnings of the narrative self.
If you haven’t guessed by now, the minimal self is ‘I’: the doer , experiencer experiencing the immediate present; the narrative self is ‘me’ -an entity stretched in time and living as much in past and future as in the present. The study authors delineate the same as follows (note that they too start with William James reference):(* references removed)
Since William James’ early conceptualization, the ‘self ’ has been characterised as a source of permanence beneath the constantly shifting set of experiences that constitute conscious life. This permanence is often related to the construction of narratives that weave together the threads of temporally disparate experiences into a cohesive fabric. To account for this continuity, William James posited an explanatory ‘me’ to make sense of the ‘I’ acting in the present moment . Recently, progress has been made in characterizing the neural bases of the processes supporting William James’ ‘me’ in the form of ‘narrative’ self-reference , highlighting the role of the medial prefrontal cortices (mPFC) in supporting self awareness by linking subjective experiences across time . The mPFC has been shown to support an array of self-related capacities, including memory for self-traits , traits of similar others , reflected self-knowledge , and aspirations for the future . As such, cortical midline processes may be characterised as supporting narrative self-reference that maintains continuity of identity across time .
Narrative self-reference stands in stark contrast to the immediate, agentic ‘I’ supporting the notion of momentary experience as an expression of selfhood. Most examinations of self-reference ignore mechanisms of momentary consciousness, which may represent core aspects of self-experience achieved earlier in development and may have evolved in earlier animal species. Indeed, little is known about whether the neural substrates underlying momentary self-reference are one and the same, or distinct from, cortical midline structures supporting narrative experience. One hypothesis suggests that awareness of momentary self-reference is neurally distinct from narrative self-reference and is derived from neural markers of transient body states, in particular, right lateralised exteroceptive somatic and interoceptive insular cortices. In the present study, we examined this thesis.
In short using fMRI, they tried to find the different hypothesized neural networks underlying the two senses of self and did find evidence for clear segregation in those practicing mindfulness meditation. Their methodology however, is not fool proof and this they themselves note in their conclusions. Here are their findings:
Consistent with a theory of self-reference as mentalising, linguistically mediated and of higher order executive origin , participants engaged midline prefrontal cortices and a left lateralised linguistic-semantic network (inferior lateral PFC, middle temporal and angular gyri) during NF (narrative focus: ‘me’ condition). Demonstrating a default bias towards NF as previously revealed in ‘resting’ mind wandering states , relatively restricted reductions in the cortical midline network were found when attention was explicitly directed towards a moment-to-moment EF (experiential focus: ‘I’ condition) in novice participants with little training in this form of self-reflection. These individuals revealed increased left lateralised prefrontal-parietal activations during EF likely reflecting greater task-related linguistic processing that has been shown to be associated with decreased medial prefrontal recruitment .
So what they found was that a part of default network was engaged in ‘me’ condition; while task-related areas were recruited in “I” condition and appropriate task-related suppression of some part of default network observed. This effect was with naive subjects, but with those trained in mindfulness meditation, they observed a sort of double dissociation:
Following an intensive 8 week course in mindfulness meditation, during which individuals learn to develop the capacity to monitor moment-to-moment experience, EF resulted in a pronounced shift away from midline cortices towards a right lateralised network comprised of the ventral and dorsolateral PFC, as well as right insula, SII and inferior parietal lobule. Consistent with a dual-mode hypothesis of self-awareness, these results suggest a fundamental neural dissociation in modes of self-representation that support distinct, but habitually integrated, aspects of self-reference: (i) higher order self-reference characterised by neural processes supporting awareness of a self that extends across time and (ii) more basic momentary self-reference characterised by neural changes supporting awareness of the psychological present. The latter, represented by evolutionary older neural regions, may represent a return to the neural origins of identity, in which self-awareness in each moment arises from the integration of basic interoceptive and exteroceptive bodily sensory processes. In contrast, the narrative mode of self-reference may represent an overlearned mode of information processing that has become automatic through practice, consistent with established findings on training-induced automaticity.
To me this sounds interesting: If I had to stretch my neck and relate this to autism and schizophrenia , I would say that based on earlier coverage on this blog: Schizophrenics have a higher default brain activity and perhaps try to spin too much of a narrative. Perhaps they are the ones that would best benefit with mindfulness meditation trainings to calm their default ‘me’ and activate the ‘I’ also at relevant times. On the opposite side, one is all too aware of the here-and-now feeling of self that many autistics have- a direct and immediate perceptual relation with world. Perhaps, they too can benefit from some for of mindfulness meditation by learning to use the default brain network too at times – letting teh mind wander and spinning a tale (however fictional) about themselves.
Farb, N., Segal, Z., Mayberg, H., Bean, J., McKeon, D., Fatima, Z., & Anderson, A. (2007). Attending to the present: mindfulness meditation reveals distinct neural modes of self-reference Social Cognitive and Affective Neuroscience, 2 (4), 313-322 DOI: 10.1093/scan/nsm030
Gallagher, S. (2000). Philosophical conceptions of the self: implications for cognitive science Trends in Cognitive Sciences, 4 (1), 14-21 DOI: 10.1016/S1364-6613(99)01417-5