Comprehensive Notes on Neuroplasticity, Brain Anatomy, and Psychological Disorders

Neuroplasticity and Recovery from Severe Brain Injury

  • Definition of Neuroplasticity: The brain's ability to reorganize itself by forming new neural pathways. This allows the brain to compensate for injury or adjust to new situations.

    • Every activity—walking, talking, chewing, drinking, and breathing—follows specific neural pathways. When these pathways are injured or destroyed, the brain must create entirely new ones to restore function.
    • Age and Recovery: The younger an individual is, the higher the degree of neuroplasticity. Children have a significantly better chance of creating new neural pathways to regain lost motor and speech functions compared to adults.

  • Case Study: Pediatric Trauma and Microsurgery:

    • A child suffered an injury where his brain had to independently create new pathways to walk and talk again.
    • Microsurgery at CHOP: The child was treated at the Children's Hospital of Philadelphia (CHOP) by a physician from the East Coast specializing in microsurgery to reconnect tear ducts.
    • Procedure Complexity: While eye surgery is generally considered microsurgery, performing it on a child is classified by the speaker as "super microsurgery."
    • Outcome: Traditionally, such an injury would require a permanent eye patch and constant saline administration to prevent the eye from drying out. The physician successfully reattached the tear ducts, allowing for natural tear production. The child eventually recovered to play baseball and join his middle school team.
    • Recovery Progression: The process was gradual, moving from a walker to crutches, then to a single crutch. Because the child was young, his neural pathways for speech were not yet fully established, making it easier for his brain to develop the necessary connections.

Human Echolocation and Differences in Ability

  • Echolocation in Humans: Like bats and dolphins, some vision-impaired individuals utilize echolocation.

    • The Case of Daniel Kish: A man blind since birth who uses clicking sounds to navigate.
    • Mechanism: He emits small sounds (clicks) that bounce off surrounding items. His brain processes the returning sound to create a "mind's eye" map of his environment.
    • Sound Processing: The volume and softness of the returning sound indicate the distance of objects. He does not know the visual appearance of a rock formation, but he understands its auditory profile.

  • Perspective on Disability: The speaker prefers the term "difference of ability" over "disability."

    • Some vision-impaired individuals choose not to use a white cane to avoid the stigma associated with blindness.
    • Anecdote on Balance: The speaker notes they personaly struggle with balance even on flat surfaces, whereas some vision-impaired individuals navigate much more effectively. The speaker wore high-heeled sneakers at their wedding to avoid tripping and generally avoids high heels.

Hearing Impairment and Community Identity

  • Gallaudet University: A university specifically for the deaf and hearing-impaired, though hearing individuals who work with the community also attend.
  • Deaf President Now Movement: A documentary and historical event at Gallaudet University. For most of its history, the university did not have a deaf or hard-of-hearing president or vice president. The student body protested to successfully elect a deaf president, arguing that understanding the community is paramount to leading the institution.
  • Professional Empathy: The speaker draws a parallel to clinical work: one does not need to have been an addict to treat addiction, nor have experienced clinical depression or anxiety to work in those fields.

Neurochemistry and Pharmacology

  • SSRIs (Selective Serotonin Reuptake Inhibitors\text{Selective Serotonin Reuptake Inhibitors}): Medications used for depression and anxiety.
    • Mechanism: They do not create or delete serotonin. Instead, they prevent the reuptake of serotonin, allowing it to remain in the synaptic gap longer so the next neuron can effectively absorb it.
  • SNRIs (Selective Norepinephrine Reuptake Inhibitors\text{Selective Norepinephrine Reuptake Inhibitors}): These work similarly to SSRIs but target norepinephrine.
  • Dopamine and Cocaine Use:
    • Cocaine use leads to the creation of more dopamine receptors.
    • Dependence: While many believe cocaine is physically addictive, the lecturer argues it is primarily a psychological dependence.
    • Receptor Behavior: The additional dopamine receptors remain while cocaine is in the system. When the drug is gone, the receptors "triple up" and eventually die off. This death of receptors causes the user to feel as if they are "in the dark" or suicidal, prompting further use to regain that feeling.

The Nervous System: Autonomic and Somatic

  • Autonomic Nervous System: Handles self-regulated actions of internal organs (e.g., digestion, lung function, heart rate). This system operates automatically without conscious thought.

    • Sympathetic Nervous System: This system is "arousing." It activates during high-stress situations (e.g., being chased by zombies). It diverts energy away from non-essential functions like digestion (e.g., your stomach won't process a "dog judge food" in a crisis).
    • Parasympathetic Nervous System: This system is "calming" and restores the body to a state of rest.

  • Somatic Nervous System: Governs sensory input and motor output.

    • Example: Touching something hot is the sensory input. The reflexive action of pulling your hand away is the motor output.
    • Reflexive Action: Doctors test reflexes (like the knee-jerk or hand grip) because a lack of response indicates nerve damage. These responses are automatic and universal regardless of race or gender.

Functional Brain Anatomy and Surgery

  • Anatomy Differences: There are minor differences in the amygdala between males and females, but they are not significant enough to account for major differences in function. The physical brain is essentially the same.
  • Corpus Callosum: Referred to by the speaker as a "Saran wrap" that covers and connects the two hemispheres of the brain.
  • Awake Brain Surgery: Common for Parkinson's disease or epilepsy. Surgeons activate specific parts of the brain to identify the source of seizures or tremors.
    • Split-Brain Surgery: A Nobel Prize-winning procedure involves cutting a portion of the corpus callosum to stop the electrical misfiring between hemispheres, which reduces Parkinson's-style shaking and epileptic seizures.
  • Lobes of the Brain:
    • Frontal Lobe: Associated with personality and higher-level processing.
    • Temporal Lobe: Located by the temples; contains the visual cortex (seeing stars when hit) and speech areas.
    • Speech Areas:
      • Broca’s Area: Involved in speech production (musculature and breath).
      • Wernicke’s Area: Involved in comprehension and word development.
    • Occipital Lobe: Located at the back of the head.
    • Cerebellum: Known as the "little brain," located near the occipital lobe.

Schizophrenia and Frontal Lobe Development

  • Onset: Schizophrenia typically appears around the same age that frontal lobe development concludes. The two are believed to be related, though the exact mechanism is unknown.
  • Triggers: Traumatic brain injury (TBI\text{TBI}), heavy alcohol use, and psychedelics can trigger the onset of schizophrenia.
  • Case Study: Brian Wilson: The Beach Boys member suffered from schizophrenia linked to massive usage of psychedelics.
    • Exploitation: He paid a therapist over $100,000\$100,000 per month to live with him, but the therapist was reportedly abusive.
    • Charles Manson Connection: Wilson famously wrote music with Charles Manson, though the music was never widely utilized in that context.

CTE and Sports-Related Head Injuries

  • Chronic Traumatic Encephalopathy (CTE\text{CTE}): A brain condition associated with repeated head trauma.
  • Aaron Hernandez Case: The former Patriots player's brain showed significant damage. The speaker notes his father's treatment and early football concussions as factors.
  • League Rules: The NFL instituted rules where a player must leave the game for at least one play if they lose their helmet and must sit out if a concussion is suspected.
  • Rugby vs. Football: In Rugby, players are taught to tackle differently because they do not wear helmets, reducing head-first impacts.
  • Will Smith Movie: The film Concussion details the NFL's knowledge of head injury risks.
  • Case of Junior Seau (Implied): Many players, including a famous Samoan player in California, have committed suicide by shooting themselves in the chest to preserve their brain tissue for CTECTE research.

Historical and Clinical Case Studies of Brain Injury

  • Phineas Gage: A railroad worker who had a metal rod driven through his brain.
    • Personality Transformation: Previously a "nice guy" and well-liked, he became aggressive and "an asshole" following the injury. This case is a primary example of how the frontal lobe impacts personality.
  • Case Study: Kevin: At age $17\$17, Kevin's car was crushed by a trash truck. He had approximately 8%8\% to 12%12\% of his brain tissue removed.
    • Adaptation: He attended college at age $28\$28. To focus, he used a visual ritual of putting his fingers together to drown out distractions, effectively creating new ways to manage his thoughts despite his brain injury.

Clinical Psychology Misconceptions

  • Schizophrenia vs. DID: The media often incorrectly equates schizophrenia with having multiple personalities.
    • Dissociative Identity Disorder (DID\text{DID}): Characterized by distinctly different personalities (different writing styles, spelling, and behavior).
    • Borderline Personality Disorder (BPD\text{BPD}): A disorder characterized by relationship instability and disproportionate emotional responses.
  • The Sybil Myth: The speaker notes a famous case (likely Sybil) where a therapist allegedly fabricated or encouraged multiple personalities to build a career through books and movies.

Sleep Disorders

  • Stages of Sleep: There are various stages, including REMREM (Rapid Eye Movement\text{Rapid Eye Movement}) sleep.
  • Fatal Familial Insomnia: Mention of a family in the United Kingdom where members cannot reach REMREM sleep. The oldest age achieved in this family is approximately $35\$35 before they succumb to the disorder.

Questions & Discussion

  • Question on Eye Surgery: A student asked if the speaker could see the surgery.
    • Response: The speaker (referencing a personal eye procedure at age $51\$51) noted they had to be awake. They could see the tweezers coming toward the eye. Because of past metal fragment history, they must undergo a full orbital X-ray before any MRI.
  • Question on Phineas Gage: A student questioned if Gage's personality change was solely brain-related or due to the trauma of the accident.
    • Response: The general consensus in psychology is that it was the specific brain areas injured, though trauma likely played a role. His behavior change included becoming abusive toward his wife and children.
  • Question on Brain Removal: A student asked if removing the "focus area" of the brain would prevent someone from learning to speak again.
    • Response: Recovery depends on multiple procedures and the age of the patient. The speaker cited a young girl who underwent multiple procedures at the University of Pittsburgh and is currently doing well.