Modern neuroscience Room for the soul By John
Modern neuroscience: Room for the soul? By John Beggs
Outline • • • Introduction Neuroscience background Free Will Ethics God Conclusions
Outline • • • Introduction Neuroscience background Free Will Ethics God Conclusions
Apollo’s chariot…
…or rotation of the earth?
Science killed Apollo. Will neuroscience kill the soul?
Dualism Body Mind Rene Descartes
Dualism Body and mind are separate The mind influences the body Mind is the fundamental truth Rene Descartes
The modern view: monism Antonio Damasio The brain produces the mind Body, or matter, is the fundamental truth
The conflict
The conflict • Dualism: Just as mind is separate from the body, so Free Will, Ethics and God originate independently of the brain.
The conflict • Dualism: Just as mind is separate from the body, so Free Will, Ethics and God originate independently of the brain. • Monism: Just as the brain produces mind, so Free Will, Ethics and God are merely products of the brain.
Outline • • • Introduction Neuroscience background Free Will Ethics God Conclusions
Trying to explain different levels macroscopic mesoscopic microscopic
Cortical neurons from rat ~1010 neurons in human brain
voltage Neurons generate voltage pulses time
Output is communicated by pulses through synapses voltage Memory? time
Each neuron makes and receives many connections ~ 103 – 104 inputs ~ 103 – 104 outputs
If all the inputs exceed a threshold, the neuron will “fire” in in Otherwise, it won’t out
From the lab of David Mc. Cormick, Yale University
Logical operations: AND gate If C has a threshold of 2, then it will fire only when A AND B fire A C B
Logical operations: OR gate If C has a threshold of 1, then it will fire when A OR B fire A C B
Neurons form networks for processing information
Networks form the cortical “sheet”
The cortical sheet is responsible for higher functions
Beggs lab: small sections of the sheet In collaboration with Alan Litke, UC Santa Cruz
Functions are partially localized in cortex Cortical structure is fairly uniform
EEG: Electro-encephalogram Measures electrical activity through the skull
PET scan: Positron emission tomography Measures glucose metabolism
f. MRI: functional magnetic resonance imaging Measures blood-oxygen level dependent responses
TMS: Transcranial magnetic stimulation Bulk stimulates cortical regions
Outline • • • Introduction Neuroscience background Free Will Ethics God Conclusions
Every physical system that has been investigated has turned out to be either deterministic or random. “Both are bad news for free will, ” he said. So if human actions can’t be caused and aren’t random, he said, “It must be — what — some weird magical power? ” - Michael Silberstein
Every spear tip we have ever seen has been made of either flint or bone. Both are bad news for tungsten. So if you claim that “tungsten” isn’t flint and can’t be bone, it must be – what – some weird new material? - Cave Man
Dualist: Free will could exist independently of some of our brain processes. Monist: Free will is produced by our brain, and might even be an illusion.
Benamin Libet’s experiment
Readiness potential precedes will to move
You thought you were deciding, but the decision was already made by that point! Therefore, there is no free will.
Not so fast…why not this: Hand movement Prepotential Will Conscious reflection “I have decided” on decision Are there any examples of our awareness “lagging behind”?
Blindsight (Lawrence Weiskrantz)
So, conscious awareness can come after recognition
Also… Low-level processes are often automatic: I can tie my shoes without thinking about it; I can drive home in my sleep. I have subconscious biases in my thoughts. Do these low-level processes truly reflect my will, or do they just reflect my tendencies?
Implicit Association Test (IAT) https: //implicit. harvard. edu/implicit/
Implicit Association Test (IAT) https: //implicit. harvard. edu/implicit/ or Good or Evil Laughter
So… My tendencies could be detected by electrodes, or by questions that you ask me. But I do not necessarily act on all my tendencies. Example: I may be angry at someone, but I may chose to forgive them. Which takes more “willpower”: anger or forgiveness?
Free Will • Free will may be a new type of process, as yet not fully understood.
Free Will • Free will may be a new type of process, as yet not fully understood. • Signals of my intentions may come before my sensed decision. But my choice may actually come before both.
Free Will • Free will may be a new type of process, as yet not fully understood. • Signals of my intentions may come before my sensed decision. But my choice may actually come before both. • We have many strong automatic tendencies, but these are often overruled by our will.
Outline • • • Introduction Neuroscience background Free Will Ethics God Conclusions
Neuroethics “the examination of how we want to deal with the social issues of disease, normality, mortality, lifestyle, and the philosophy of living informed by our understanding of underlying brain mechanisms” -The Ethical Brain, by Michael Gazzaniga (emphasis his)
Prefrontal lesions: amoral behavior Phineas Gage
Clearly, the health of our brain affects our ability to make moral choices. But should we also look to the brain to tell us what is morally right? If you are a dualist, then no. If you are a monist, then yes.
Jonathan Cohen
A runaway trolley is hurtling down the tracks toward five people who will be killed if it proceeds on its present course. The only way to save them is to hit a switch that will turn the trolley onto an alternate set of tracks where it will kill one person instead of five. Most people hit the switch, saving five
As before, a trolley threatens to kill five people. You are standing next to a large stranger on a footbridge that spans the tracks in between the oncoming trolley and the five people. In this scenario, the only way to save the five people is to push this stranger off the bridge, onto the tracks below. He will die if you do this, but his body will stop the trolley from reaching the others. Most people refrain from pushing, letting five die
How does the brain respond to these two dilemmas? “Emotional” areas (footbridge dilemma) “Cognitive” areas (trolley dilemma)
Going further: Should one smother a crying baby to death to protect the lives of many when enemy soldiers are approaching? Here they compared the activation patterns in the brains between those who approve (utilitarians) and those who do not (deontologists). Deontologists: Don’t smother – “emotional” brain areas dominate Utilitarians: Smother – “cognitive” brain areas dominate
"The social-emotional responses that we've inherited from our primate ancestors. . . undergird the absolute prohibitions that are central to deontology. In contrast, the 'moral calculus' that defines utilitarianism is made possible by more recently evolved structures in the frontal lobes that support abstract thinking and high-level cognitive control. " - Greene and Cohen
(Descriptive) Before, they were telling us how the brain responded to these dilemmas. (Prescriptive) Now they seem to be suggesting what we should do.
If they are correct…
If they are correct… • Utilitarianism, being most recent, is correct
If they are correct… • Utilitarianism, being most recent, is correct • Deontological views, being most ancient, are incorrect
If they are correct… • Utilitarianism, being most recent, is correct • Deontological views, being most ancient, are incorrect • Joshua Greene should give up his federal research funding, because we could feed many more people than just him with it.
If they are correct… • Utilitarianism, being most recent, is correct • Deontological views, being most ancient, are incorrect • Joshua Greene should give up his federal research funding, because we could feed many more people than just him with it. • Intellectual superiority equates with moral superiority
Outline • • • Introduction Neuroscience background Free Will Ethics God Conclusions
Does God exist?
Does God exist? Dualist: God could exist independently of our minds
Does God exist? Dualist: God could exist independently of our minds Monist: God only exists in our minds
Julian Jaynes (1920 -1997) God’s voice? That’s just the other hemisphere talking.
Temporal lobe epilepsy (TE) There are…recent examples [of TE], like one of the founders of the Seventh Day Adventist Movement, Ellen White. Born in 1827, she suffered a brain injury aged 9 that totally changed her personality. She also began to have powerful religious visions. Disruptions of this general area may also lead to increased ritual behavior.
Michael Persinger 80% of Dr Michael Persinger's experimental subjects report that an artificial magnetic field focused on …[left temporal lobe] brain areas gives them a feeling of 'not being alone'. Some of them describe it as a religious sensation.
Scientists like Andrew Newberg want to see just what does happen during moments of faith. He worked with Buddhist, Michael Baime, to study the brain during meditation. By injecting radioactive tracers [PET scan] into Michael's bloodstream as he reached the height of a meditative trance, Newberg could use a brain scanner to image the brain at a religious climax. So, religion is something that only happens occasionally?
Out-of-body experience?
Even Richard Dawkins…
The “God Module” People with temporal lobe epilepsy had religious hallucinations After seizures, they were more prone to prefer religious words over erotic words. Control group preferred erotic words. V. S. Ramachandran
I see my wife; she produces activity in my visual cortex Seizure or stimulation causes activity in my visual cortex even when my wife is not there. Therefore, my wife is always an illusion?
Religion is not just: • • Feeling another presence An out-of-body experience Ritual A climactic moment of faith
Just because activity in the brain correlates with experiences of God does not mean that God does not exist.
Outline • • • Introduction Neuroscience background Free Will Ethics God Conclusions
Conclusions • Mental functions are produced by the brain
Conclusions • Mental functions are produced by the brain • This includes mechanisms of will, moral choice, and perceptions of God
Conclusions • Mental functions are produced by the brain • This includes mechanisms of will, moral choice, and perceptions of God • From this it does not follow that:
Conclusions • Mental functions are produced by the brain • This includes mechanisms of will, moral choice, and perceptions of God • From this it does not follow that: • Free will is an illusion
Conclusions • Mental functions are produced by the brain • This includes mechanisms of will, moral choice, and perceptions of God • From this it does not follow that: • Free will is an illusion • Utilitarianism is correct
Conclusions • Mental functions are produced by the brain • This includes mechanisms of will, moral choice, and perceptions of God • From this it does not follow that: • Free will is an illusion • Utilitarianism is correct • God is an illusion
Accept the science, but be critical of the non-scientific conclusions.
Other interesting topics • • • “Mind reading” f. MRI scans Remote control of rats Neural control of prosthetic limbs Mentally moving a cursor for shut in patients Closed loop experiments: “Brain in a dish” Split brain experiments Hemineglect Prosopagnosia The case of H. M. ; no new memories “Gay” rams? Spiritual machines?
Modern neuroscience: Room for the soul? Thanks! By John Beggs
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Religious experience has a cognitive component Differences between happy emotions and religious thoughts involve cognitive areas
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