Brain Science with Ginger Campbell, MD – Episode 214

Seventeenth Annual Review Episode
Release Date: December 15, 2023
Host: Dr. Ginger Campbell

Overview

Episode 214 of Brain Science marks the 17th anniversary of the podcast and serves as a comprehensive review of the year’s episodes. Dr. Ginger Campbell reflects on highlights from recent conversations with leading neuroscientists, biologists, psychologists, and philosophers, offering listeners a curated summary of key insights about free will, plant intelligence, misinformation, the emotional-cognitive brain, synaptic biology, and consciousness. The episode concludes with an important announcement regarding the future of the podcast.

Key Discussion Points & Insights

1. Free Will and Agency: Kevin Mitchell’s “Free Agents”

[00:23 – 10:10]

• Dr. Campbell opens with a review of her recent conversation with Kevin Mitchell and his book, “Free Agents: How Evolution Gave Us Free Will.”
• Mitchell’s view challenges the mainstream neuroscience and philosophy positions that argue free will is an illusion.
• Core Arguments:
  • Evolution and Agency: Agency began at the dawn of life, even with single-celled organisms making meaningful choices to survive.
    • “Free will implies the ability to make meaningful choices, and Mitchell argues that this ability evolved with the emergence of life. Even single celled life forms have agency because they make simple choices like going toward food and away from threats.” (Dr. Campbell, [02:28])
  • Against Determinism: Mitchell questions the physicalist, deterministic worldview, noting that quantum mechanics’ indeterminacy means physics does not conclusively deny free will.
    • “To me, it is ironic that many consider determinism to be a highly scientific position rather than a philosophical one...” (Dr. Campbell, [04:52])
  • Human Free Will and Responsibility: Humans have unprecedented reflective abilities, increasing our responsibility for our choices.
  • Reconsidering the Unconscious: Evidence for unconscious determination of behavior (e.g., Libet’s experiments) is contested, with experimental design affecting conclusions.
• Related Reading:
  • Robert Sapolsky’s “A Science of Life Without Free Will”
  • Ben Newell & David Shanks’ “Open: Searching for the Truth about the Unconscious Mind”

2. Molecular Biology in Neuroscience: Guy Caldwell & C. elegans

[10:10 – 21:54]

• Dr. Guy Caldwell (Episodes 204, 205) is highlighted for his work with the roundworm C. elegans as a model organism for Parkinson’s disease.
• Molecular Biology:
  • Defined as studying molecules like DNA, RNA, and proteins—the “molecules of life.”
  • Not to be confused with genetic engineering, though the fields overlap.
    • “In biology, everything is DNA.” (Guy Caldwell, paraphrased [13:40])
• Innovative Tools:
  • Green fluorescent protein (GFP) tagging and optogenetics.
• Model Organisms:
  • Advantages of using C. elegans: transparency, known wiring diagram, simplicity (eight dopamine neurons), genetic similarity to humans.
  • Allows genetic manipulation and testing of potential treatments at a fundamental level.
• Clinical Relevance:
  • Insights from model organisms contribute to “predictive preclinical models” and progress toward personalized or precision medicine, especially in neurology and cancer.
• Key Takeaway:
  • Breakthroughs rely on interdisciplinary work and the realization that “all life uses the same building blocks.”

3. Plant Intelligence: Paco Calvo and the Minimal Intelligence Lab

[21:55 – 27:23]

• Dr. Paco Calvo (Episode 206) investigates the intelligence of plants, as discussed in his book “The New Science of Plant Intelligence.”
• Key Concepts:
  • Plants can be anesthetized, and display electrical activity akin to animals.
  • Speed of Life: Plants’ actions occur on much slower timescales, needing time-lapse photography to observe.
  • Signaling Molecules: Plants use the same molecules (e.g., neurotransmitters, melatonin) as animals and even bacteria.
• Defining Intelligence:
  • Intelligent behavior is adaptive, flexible, influenced by experience, proactive, and predictive—not just reflexive.
    • Example: Sun-tracking in certain plants.
    • “If you’re a slow moving plant, your actions have got to fit the conditions that are going to exist in the future.” (Paco Calvo, paraphrased [25:12])
  • Domesticated plants are often “less intelligent,” analogous to underestimating animals outside wild contexts.
• Embodied Cognition:
  • Intelligence is not limited to brains; it’s shaped by an organism’s body and its environment.
  • The “4 E’s”: Embodied, Embedded, Extended, Enactive.
• Unresolved Questions:
  • Whether plants can exhibit associative learning remains contentious.
  • Recommendation:
    • Focus research on plant intelligence over the more controversial topic of plant consciousness.

4. Misinformation & Immunity to Manipulation: Xander van der Linden

[27:23 – 30:15]

• Dr. Xander van der Linden (Episode 208) explores why misinformation spreads, and how to immunize ourselves against it, in his book “Foolproof.”
• The Psychology of Conspiracy Theories:
  • People who embrace conspiracy theories share common psychological traits and often hold multiple, even contradictory, beliefs.
  • Mnemonic – “CONSPIRE”:
    • C: Contradictory thinking
    • O: Overriding suspicion
    • N: Nefarious intent
    • S: Something must be wrong
    • P: Persecuting victim
    • I: Immunity to evidence
    • R: Reinterpreting randomness (Dr. Campbell, [28:03])
• Practical Application:
  • Video games designed to teach detection of manipulative tactics can build resilience.
• Health Tie-In:
  • Conspiracies around vaccination exemplify how misinformation impacts public health.

5. The Cognitive-Emotional Brain: Luis Pessoa

[30:16 – 36:06]

• Dr. Luis Pessoa (Episodes 209, 213) challenges the outdated modular view of the brain in favor of an “entangled” model where cognition and emotion are intertwined.
• Main Assertions:
  • Emotion and cognition are not segregated in the brain; for example, the amygdala is involved in decision making, arousal, attention, as well as emotion.
    • “Cognition begins before you get to the cortex. Emotion and cognition can’t be separated in terms of where they occur in the brain.” (Luis Pessoa, summarized by Dr. Campbell, [32:06])
  • The pulvinar nucleus of the thalamus is a central hub, not a mere relay; it’s only responsive to consciously perceived stimuli and modulates cortical activity.
• Multiple Waves Model:
  • Information flows are recursive and networked—not linear.
  • Individual neurons can participate in multiple brain networks.
• Challenge to Modularity:
  • Brain regions traditionally assigned to specific functions (emotion, cognition, sensation) are more multifunctional than previously thought.
• Broader Implications:
  • The need for new, dynamic research methods and interdisciplinary approaches.

6. Neurotransmitters & Synaptic Biology:

a. Review of Neurotransmitters (Episode 210)

[36:27 – 39:30]

• Key point: Neurotransmitters’ effects are determined by receptor type and location, not by the neurotransmitter itself.
  • Example: Dopamine is not just a “reward molecule,” but participates in many processes.
    • “It is inaccurate to describe any neurotransmitter by a single action… it’s really all about the receptors.” (Dr. Campbell, [38:06])
• There are two types of receptors:
  • Ionotropic (fast, ligand-gated ion channels)
  • Metabotropic (slower, G-protein coupled)

b. Seth Grant – The Complexity of the Synapse (Episode 211)

[39:31 – 43:37]

• Dr. Seth Grant’s research found synapses contain thousands of proteins, many predating the evolution of nervous systems.
• The Cambrian explosion may have been enabled by genome duplications, expanding the protein toolkit.
• Distribution of synaptic proteins changes with age and in mouse models of neuropsychiatric disease.
  • More “long-lived” synapse proteins are present in aging and models of autism/schizophrenia.
• Clinical Implications:
  • Understanding protein turnover at the synapse has ramifications for neurological disease and treatment development.

7. Consciousness & Selfhood: Thomas Metzinger’s “The Ego Tunnel”

[43:38 – 47:15]

• Metzinger (Episode 212) asserts that consciousness is a biological process, including the experience of 'self.'
  • The “ego tunnel”: Consciousness is an internally generated process, providing only a limited, selective view of reality.
  • Out-of-body and virtual reality experiments show the embodied nature of self-awareness.
  • “Any valid theory of consciousness should include an explanation of altered states.” (Thomas Metzinger, paraphrased [43:54])
• Embodiment:
  • The sense of self is fundamentally linked to bodily sensations and perceptions.
• Metzinger’s new book, “The Elephant and the Experience of Pure Consciousness,” is mentioned as forthcoming in February 2024.

Notable Quotes & Memorable Moments

• On Free Will:

  • “Free will implies the ability to make meaningful choices... Even single celled life forms have agency...”
    (Dr. Campbell, [02:28])

• On the Role of the Synapse:

  • “Grant made two surprising discoveries. One was that synapses actually contained thousands of proteins... many of the proteins that are critical to synapse function are present in single celled organisms like fungi. This means that the proteins came before the evolution of the nervous system.”
    (Dr. Campbell, summarizing Seth Grant, [41:08])

• On Plant Cognition:

  • “It is generally assumed that whatever behaviors plants do have is merely reflexive. In order for behavior to be intelligent, it has to be adaptive and flexible... proactive, anticipatory and predictive.”
    (Dr. Campbell, [24:15])

• On Mis-/Disinformation:

  • “When someone decides not to be vaccinated, their choice affects those around them, not just because herd immunity requires a high level of vaccination, but because there will always be those who can't be vaccinated or whose immune systems are too weak to respond properly.”
    (Dr. Campbell, [28:35])

Major Timestamps

• 00:23 – Episode introduction and transition to year’s review
• 02:28 – Kevin Mitchell’s free will argument
• 13:40 – Guy Caldwell on molecular biology & the significance of DNA
• 21:55 – Plant intelligence and embodied cognition (Paco Calvo)
• 27:23 – Spread and psychology of misinformation (Xander van der Linden)
• 30:16 – Emotion and cognition as entangled processes (Luis Pessoa)
• 36:27 – Review of neurotransmitters
• 39:31 – Synapse complexity and protein dynamics (Seth Grant)
• 43:38 – Consciousness, selfhood, and “The Ego Tunnel” (Thomas Metzinger)
• 47:15 – End – Announcement regarding the future of Brain Science

Important Announcement & Podcast Future

• Dr. Campbell announces that due to her relocation and new role as a physician in New Zealand, she will pause the production of new Brain Science episodes to focus on her personal and professional life.
• Podcast archives remain available:
  • Free content: All episodes from December 2016 onward, and year-end/encore episodes.
  • MyLipson Premium: Access to archives from 2006–2016 for a small fee.
  • Patreon: Supports continued access and website upkeep.

Conclusion

Episode 214 provides an accessible, high-level overview of the latest research and perennial questions in neuroscience, as explored over 17 years of Brain Science. From debates about free will and consciousness to the intricate biology of synapses and the intelligence of plants, Dr. Campbell highlights how neuroscience is best understood via interdisciplinary approaches and humility about the complexity of the brain and mind. The show’s tradition of making cutting-edge neuroscience accessible to all continues in this review—an apt celebration of its enduring legacy.