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Modern neuroscience: Room for the soul? By John Beggs.

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Presentation on theme: "Modern neuroscience: Room for the soul? By John Beggs."— Presentation transcript:

1 Modern neuroscience: Room for the soul? By John Beggs

2 Outline Introduction Neuroscience background Free Will Ethics God Conclusions

3 Outline Introduction Neuroscience background Free Will Ethics God Conclusions

4 Apollo’s chariot…

5 …or rotation of the earth?

6 Science killed Apollo. Will neuroscience kill the soul?

7 Dualism Rene Descartes Body Mind

8 Dualism Rene Descartes Body and mind are separate The mind influences the body Mind is the fundamental truth

9 The modern view: monism Antonio Damasio The brain produces the mind Body, or matter, is the fundamental truth

10 The conflict

11 Dualism: Just as mind is separate from the body, so Free Will, Ethics and God originate independently of the brain.

12 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.

13 Outline Introduction Neuroscience background Free Will Ethics God Conclusions

14 Trying to explain different levels macroscopic mesoscopic microscopic

15 Cortical neurons from rat ~10 10 neurons in human brain

16 Neurons generate voltage pulses time voltage

17 Output is communicated by pulses through synapses time voltage Memory?

18 Each neuron makes and receives many connections ~ 10 3 – 10 4 outputs ~ 10 3 – 10 4 inputs

19 If all the inputs exceed a threshold, the neuron will “fire” out in Otherwise, it won’t

20 From the lab of David McCormick, Yale University

21 Logical operations: AND gate A B C If C has a threshold of 2, then it will fire only when A AND B fire

22 A B C If C has a threshold of 1, then it will fire when A OR B fire Logical operations: OR gate

23 Neurons form networks for processing information

24 Networks form the cortical “sheet”

25 The cortical sheet is responsible for higher functions

26 Beggs lab: small sections of the sheet In collaboration with Alan Litke, UC Santa Cruz

27 Cortical structure is fairly uniform Functions are partially localized in cortex

28 EEG: Electro-encephalogram Measures electrical activity through the skull

29 PET scan: Positron emission tomography Measures glucose metabolism

30 fMRI: functional magnetic resonance imaging Measures blood-oxygen level dependent responses

31 TMS: Transcranial magnetic stimulation Bulk stimulates cortical regions

32 Outline Introduction Neuroscience background Free Will Ethics God Conclusions

33 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

34 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

35 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.

36 Benamin Libet’s experiment

37 Readiness potential precedes will to move

38 Therefore, there is no free will. You thought you were deciding, but the decision was already made by that point!

39 Not so fast…why not this: Will Hand movement Conscious reflection on decision Prepotential “I have decided” Are there any examples of our awareness “lagging behind”?

40 Blindsight (Lawrence Weiskrantz)

41 So, conscious awareness can come after recognition

42 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?

43 Implicit Association Test (IAT) https://implicit.harvard.edu/implicit/

44 Laughter or Good or Evil

45 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?

46 Free Will Free will may be a new type of process, as yet not fully understood.

47 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.

48 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.

49 Outline Introduction Neuroscience background Free Will Ethics God Conclusions

50 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)

51 Prefrontal lesions: amoral behavior Phineas Gage

52 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.

53 Jonathan Cohen

54 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

55 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

56 “Emotional” areas (footbridge dilemma) “Cognitive” areas (trolley dilemma) How does the brain respond to these two dilemmas?

57 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

58 "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

59 (Descriptive) Before, they were telling us how the brain responded to these dilemmas. (Prescriptive) Now they seem to be suggesting what we should do.

60 If they are correct…

61 Utilitarianism, being most recent, is correct

62 If they are correct… Utilitarianism, being most recent, is correct Deontological views, being most ancient, are incorrect

63 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.

64 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

65 Outline Introduction Neuroscience background Free Will Ethics God Conclusions

66 Does God exist?

67 Dualist: God could exist independently of our minds

68 Does God exist? Dualist: God could exist independently of our minds Monist: God only exists in our minds

69 Julian Jaynes ( ) God’s voice? That’s just the other hemisphere talking.

70 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. Temporal lobe epilepsy (TE) Disruptions of this general area may also lead to increased ritual behavior.

71 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.

72 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?

73 Out-of-body experience?

74 Even Richard Dawkins…

75 The “God Module” V.S. Ramachandran 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.

76 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?

77 Religion is not just: Feeling another presence An out-of-body experience Ritual A climactic moment of faith

78 Just because activity in the brain correlates with experiences of God does not mean that God does not exist.

79 Outline Introduction Neuroscience background Free Will Ethics God Conclusions

80 Mental functions are produced by the brain

81 Conclusions Mental functions are produced by the brain This includes mechanisms of will, moral choice, and perceptions of God

82 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:

83 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

84 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

85 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

86 Accept the science, but be critical of the non-scientific conclusions.

87 Other interesting topics “Mind reading” fMRI 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?

88 Modern neuroscience: Room for the soul? By John Beggs Thanks!

89 Successfully uploaded 9.6MB file NeurosceinceRoomForSoulBeggs.ppt. It may be accessed via this URL: https://www.slashtmp.iu.edu/public/download.php?FILE=jm beggs/12502F84fuG https://www.slashtmp.iu.edu/public/download.php?FILE=jm beggs/12502F84fuG Or me at:

90 Religious experience has a cognitive component Differences between happy emotions and religious thoughts involve cognitive areas


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