• History of neuroscience
• Levels of analysis
• Methods to the madness

• A. The brain has more parts than any other physical entity we know about.
• B. Physicists have largely ignored biology.
• C. Nervous systems are influenced by multiple factors we can’t (yet) measure effectively.
• D. Physicists only study “toy” problems.

• A. The brain has more parts than any other physical entity we know about.
• B. Physicists have largely ignored biology.
• C. Nervous systems are influenced by multiple factors we can’t (yet) measure effectively.
• D. Physicists only study “toy” problems.

• A. Boundaries
• B. Components
• C. Interactions among components
• D. Inputs and outputs
• E. Readily predictable behavior

• A. Boundaries
• B. Components
• C. Interactions among components
• D. Inputs and outputs
• E. Readily predictable behavior

J. Lichtman, https://www.youtube.com/watch?v=nvXuq9jRWKE&feature=youtu.be

• What can observation tell us about brain and behavior?
• Vital role of tools/methods/techniques in discovery
• “If I have seen further, it is by standing on the shoulders of giants.” – Isaac Newton, 1676

• Mental functions controlled by organs in the head, i.e., the brain
• Mental functions can be influenced by substances we consume
• Head injury can impair behavior and thinking
• Something flows from brain to body via nerves

• A. Limited technology.
• B. Limited cultural support for systematic observation & description. = SCIENCE
• C. Lack of ability to use knowledge even if it were acquired.

• Reflexes “reflect” events in the world
• Not the same as voluntary functions

• Reflexes and animal “minds” are physical, machine-like
• Human mind is not
  • “Dual” influences on behavior
  • Physical + spiritual
• Soul controls body via pineal gland
  • Causes muscles to “inflate”

• A. Yes, human minds are fundamentally different from animal minds. The human mind is influenced by both physical and extraphysical processes.
• B. No, human minds are similar to animal minds. The human mind arises solely from physical processes.

• Neuroscience shaped by new methods, tools
• Neuroscience shaped by great debates
  • Mind == brain debate
  • Are functions local or distributed?
  • Nature of neural communication
• Forms at multiple levels of analysis contribute to function

• Within an individual
  • molecular
    • genetic
    • receptor
  • chemical
    • neurotransmitter/hormonal
  • cellular
    • neuronal firing

• Internal to individuals
  • network
    • lateral inhibition
  • area
    • V1 varies by ~2x
  • region
    • Wiring/connectivity differences
  • system

• External to individuals
  • Social
    • Friends, family, teachers, others
  • Non-social
    • Neighborhood, school, state/region, country
    • Physical environment

• Within one lifetime
  • Microseconds
    • detection position from acoustic stimulation
  • Milliseconds
    • action potential
  • Seconds
    • changes in EEG power
    • short-term memory

• Within one lifetime
  • Minutes
    • synaptic plasticity
  • Hours
    • memory consolidation
    • Hormone (melatonin, cortisol) levels
  • Days

• Within one lifetime
  • Weeks
  • Months
  • Years
    • education & training
    • disease processes
    • cultural change

• Across lifetimes
  • Centuries
    • cultural changes
  • Millenia
    • Natural & sexual selection

• Different methods, different levels of analysis
• Challenge of linking phenomena across levels
  • How does the micro affect macro or vice versa?
• Challenge of interpretation

• Tools in the neuroscientist’s toolkit
• What they tell us, and what they don’t

• What is the question?
• What are we measuring?
  • Structure
  • Activity
• Strengths & Weaknesses
  • Cost
  • Invasiveness
  • Spatial/temporal resolution

• Structural
  • Mapping the circuitry
  • Anatomy & connectivity
• Functional (next time)
  • What does it do?
  • Physiology/Activity

• Cell/axon stains
  • Golgi stain – whole cells
    • Camillo Golgi
  • Nissl stain – cell bodies only
    • Franz Nissl
  • Cellular distribution, concentration, microanatomy

• Neuron information flow polarized–flows in one direction
• Retrograde (from axon terminal to cell body); anterograde (from cell body to axon terminal)
• What connects where

• Invasive (in humans post-mortem only)
• High spatial resolution, but poor temporal resolution
  • Why?

• Computed axial tomography (CAT), computed tomography CT
• X-ray based

• Magnetic resonance
• Some common isotopes (e.g., H) & complex molecules have a magnetic dipole
• Axes align with strong magnetic field
• When alignment perturbed by radio frequency (RF) pulse, speed of realignment varies by tissue
• Realignment emits RF signals

• Reveals tissue density/type differences
• Gray matter (neurons & dendrites & axons & glia) vs. white matter (mostly axons)
• MR Spectroscopy
• Region sizes/volumes

• Type of structural MRI
• Reveals integrity/density of axon fibers
• Measure of connectivity

• Voxels (volume-based elements)
• Morphometry, measure (“metry”) form/morphology.
• How does brain size or thickness vary by age, disease status, etc.?

• Spatial vs. temporal resolution
• Structural methods (parts, sizes, connectivity)

• Functional neuroscience methods
• Neuroanatomy