Gray Matters: neuroscience

Showing posts with label neuroscience. Show all posts

Not a discussion between anxious people, but evolution of the nervous system.

Neurons
Origin of Intelligence
Origin of the Brain

Soul Pseudoexplanations

We're all familiar with optical illusions and the fact that our brain can be fooled in its attempts to make sense of the world.

Our brains construct a cross-correlated internal representation of external reality through experience. By cross-correlated I mean that if we see a wall within our reach, it is quite reasonable to expect that we could also touch the wall, hear it if we struck it, even smell it if we cared to get up close.

We are perceptually unaware, though, of the neural processes that are involved in constructing perception, let alone consciousness.

We are unaware of the mechanism that leads to release of adrenaline from the adrenal gland upon sensing of danger–though we are certainly aware of the physiological effect of circulating adrenaline.

Similarly, even though we are aware of emotions, we are unaware of emotional mechanisms. We recall information or events without awareness of the neural basis for memory formation. We are unaware of actin-myosin sliding although aware of muscle contraction–or of cellular secretion of hormones, or of mitosis. The examples of disconnection between cellular mechanisms and perception of those mechanisms are as numerous as our cellular activites. The apprehension problem lies partly because of matters of scale–we have evolved to be aware only of the large scale effects of cellular actions and it could not be otherwise.

Out of this divorce between mechanism and experience came mind-body dualism and the conceptualization of a motivating 'soul' beneath physiological mechanisms. Dualism is the 'common sense' idea that some kind of supernatural mechanism is intimately connect to and drives the physical. Dualism is a soul-of-the-perceptual-gap pseudoexplanation.

By extension, out of mind-body dualism came the equally ridiculous notion that some kind of transcendental 'intelligence' can operate in the universe independent of a neural substrate. Regardless of what overly argument-driven philosophers might believe, the evidence indicates that intelligence is an evolved, neural-based phenomenon. Period. End of story. Or, it should be.

(By argument-driven, I refer to the phenomenon of looking only at whether or not the construction of an argument follows the rules of logic, and whether or not the premises conform to Newtonian-level intuition.)

"The philosopher Isaiah Berlin once said that the trouble with academics and commentators is that they care more about whether ideas are interesting than whether they are true." Michael Ignatieff

I think that Berlin's comment also applies to some philosophers and definitely to theologians and apologists.

The potential for mistaken conceptualizations based on 'common sense' or intuitive reasoning ultimately led from philosophy, which sought to answer questions purely by 'thinking' about them, to experimental science that acknowledged, and compensated for, the limitation of pure rationalism. Science evolved philosophically to discard, by expert consensus, old outmoded metaphysical explanations for the physical. Philosophy, divorced as it can be from empirical testing of premises, has not necessarily discarded unsupported theories.

Theists, who must ignore the lack of evidence or counterevidence, have monopolized on this deficiency in philosophy. They call it theology or apologetics. Some of these arguments appear quite logical, but there is an inherent problem with arguments constructed purely on definition or analogy. Any philosophy that seeks to explain the physical, regardless of whether it defines itself as supernatural or ineffable, must cede the field to scientific explanations, where available, because only science can test, confirm, or falsify the physical.

Stephen Jay Gould was, I believe, quite incorrect about his appeasement position termed "non-overlapping magisteria".

apologetics, biological evolution, cell biology, cognition, intelligence, intelligent design, logic, molecular biology, neuroscience, philosophy, science, theology, Gould

Destroying Descartes' Dualism

Science of the Soul? ‘I Think, Therefore I Am’ Is Losing Force

. . . as evolutionary biologists and cognitive neuroscientists peer ever deeper into the brain, they are discovering more and more genes, brain structures and other physical correlates to feelings like empathy, disgust and joy. That is, they are discovering physical bases for the feelings from which moral sense emerges — not just in people but in other animals as well.

The result is perhaps the strongest challenge yet to the worldview summed up by Descartes, the 17th-century philosopher who divided the creatures of the world between humanity and everything else. As biologists turn up evidence that animals can exhibit emotions and patterns of cognition once thought of as strictly human, Descartes’s dictum, “I think, therefore I am,” loses its force.

René Descartes', lacking the knowledge that science offers us, conjured up another unsuccessful version of the ontological argument in which he conceived of a body-mind dualism connected at the pineal gland.

I'm never sure whether dualists interpret the evidence so as to exclude reductionist materialism because it is counterintuitive or because they wish to believe in the possibility of the continuance of their personal consciousness after physical death. I expect that it is both, and I think that their assumptions are unfounded.

I'll illustrate with a simple example. If your family doc taps your patellar tendon below the knee to test your 'knee-jerk' reflex, the neurophysiological and muscular responses are quite simple and could easily be fully 'tracked' in an animal model. (patellar reflex)

There is no need to invoke a 'knee-muscle-spirit' to explain what has happened. Your experience, though, is not directly of stretch of the Golgi tendon organ, neuronal firing, and actin-myosin sliding. You feel the tap and feel an involuntary muscle contraction. Modern dualists would undoubtedly accept the physical explanation for this experience without even thinking that a spirit-mechanism need be invoked.

However, dualists conveniently ignore the fact that this simplest reflex lies on a spectrum of neurophysiological activity/experience that extends up to consciousness. They ignore the extremely high likelihood that experiences that result from the complex, emergent system that is our plastic, input-programmed brain represent the same types of phenomenology.
They ignore the fact that the brains of different individuals become active in predictable neuroanatomical areas when those individuals engage in equivalent behaviors. If our brains were mere antennas for the mind, then we should expect to see idiosyncratic neuranatomic responses.

They conveniently ignore Occam's razor, which indicates that the most parsimonious, not necessarily the simplest, explanation is always to be preferred. They usurp the fact that highly complex physical phenomena are difficult to tease apart, and they distort this techical 'uncertainty' into metaphysical argumenta ad
ignorantiam that permit the desired conclusion.

Scientific methodology was 'invented' to counteract precisely such wishful unthinking. For my comments above, Sam [Harris] might join Lee Siegel in declaring atheism damaging to imagination. However, I think that trying to conceptualize how things and people really function is more difficult than simplistic, intuitive, flights of fantasy. That's what makes it interesting!

~ salient, here. [I have added italic emphasis and links]

Natural Selection for Altruism

Morality has a neural basis, and both morality and rationality depend on limbic-prefrontal connections. Morally loaded behaviors such as altruism are found in our primate lineage, where they provided selective survival advantages for the natural group.

So much for the religious mythology that God handed down absolute moral edicts! Well, anyone endowed with the logical-empirical cognitive attitudes that render the thinker resistant to religious inculcation could have told the sociologists and neuroscientists that small children exhibit concern for others and that much of our moral framework is learned.

Reactions to Haidt's article: on Edge by Michael Shermer, David Sloan Wilson, Sam Harris, and PZ Myers . Bulldust about atheism and morality . Haidt Hype . Misunderstanding the New Atheism . NewScientist "If morality is hard wired in the brain - What's the point of Religion?" . Morality Gene?

biological evolution

cognition