Neurobiology NDRB 3433 - Comprehensive Notes Ch 1

Central Nervous System and Peripheral Nervous System

  • CNS = brain and spinal cord; processes information and coordinates activity of the body

  • PNS = all neural structures outside the brain and spinal cord

  • Autonomic Nervous System (ANS): controls involuntary functions; subdivides into Sympathetic Division and Parasympathetic Division

  • Somatic Nervous System: governs voluntary movements and conveys sensory information from the body to the CNS

  • Sensory vs. Motor: sensory afferents bring information to the CNS; motor efferents carry commands from the CNS to muscles and glands

Brain Anatomy: Major Structures

  • Brain comprises three major parts:

    • Brain: including the Cerebrum, Cerebellum, Brain stem

    • Central nervous system (CNS) = brain + spinal cord

  • Peripheral nervous system (PNS) comprises nerves outside the CNS

Landmarks of the Cerebrum

  • Central sulcus

  • Parietal lobe

  • Frontal lobe

  • Occipital lobe

  • Sylvian fissure (lateral fissure)

  • Temporal lobe

  • Cerebellum

Historical Figures and Case References

  • Phineas Gage (1823-1860): famous case illustrating brain–behavior relationships; contributed to localization of brain function and the role of the frontal lobes in personality

  • Paul Broca (1824-1880): key figure in brain localization; associated with Broca’s area and language production; highlighted localization of function in the cortex

  • Central sulcus appears again in Broca-related context on slide

Cortex Size Across Species (Cortex in Primate vs Rodent)

  • Primate brain (cortex): approximately 7 cm7\,\text{cm} in length; corresponds to a monkey brain (Figure label: (a))

  • Rodent brain (cortex): approximately 3 cm3\,\text{cm} in length; corresponds to a rat brain (Figure label: (b))

Levels of Investigation in Neuroscience

  • A hierarchical scale from molecules up to the CNS:

    • Molecules: approximately 1 A˚1\,\text{Å}

    • Synapses: approximately 1 μm1\,\mu\text{m}

    • Neurons: approximately 100 μm100\,\mu\text{m}

    • Networks: approximately 1 mm1\,\text{mm}

    • Maps: approximately 1 cm1\,\text{cm}

    • Systems: approximately 10 cm10\,\text{cm}

    • CNS: approximately 1 m1\,\text{m}

  • In the schematic, there are abbreviations for cortical areas along the levels, e.g.: TF, MST, VP, LIP, DP, PIT (examples of regions used in cognitive and systems neuroscience)

  • Disciplines highlighted in this tiered view:

    • Cognitive Neuroscience

    • Behavioral Neuroscience

    • Systems Neuroscience

    • Cellular Neuroscience

    • Molecular Neuroscience

Major Neurodegenerative and Neurological Diseases

  • Epilepsy

  • Stroke

  • Parkinson's Disease

  • Various Neurological Disorders

  • Amyotrophic Lateral Sclerosis (ALS) [note: transcript spells "Amylotrophic Lateral Sclerosis"]

  • Alzheimer's Disease

  • Huntington's Disease

  • Multiple Sclerosis

Big Ideas from the Lecture

  • 1) Nervous system organization

  • 2) CNS vs PNS

  • 3) Introduction to the Cortex

  • 4) Phineas Gage & Paul Broca

  • 5) Brain specialization

  • 6) Levels of investigation

  • 7) Neurological diseases

Connections and Implications (summary notes)

  • The CNS/PNS distinction underpins why certain diseases affect central processing while others affect peripheral functions

  • Landmarks of the cerebrum help map functions to anatomical regions, illustrating localization of function (e.g., Broca’s work, central sulcus mappings)

  • Historical cases (Gage) and research findings (Broca) provide foundational evidence for brain localization and the link between structure and function

  • The cortex scales from primate to rodent models illustrate how brain size and cortical organization relate to cognitive capacity and methodology for studying it

  • Levels of investigation justify multiple research approaches, from molecular mechanisms to whole-system behavior, and guide experimental design

  • The listed neurodegenerative diseases emphasize clinical relevance and the need to understand structure–function relationships across scales

Hypothetical scenarios and practical implications

  • If a lesion disrupts the central sulcus, expect motor deficits due to disruption of primary motor areas (illustrating structure–function mapping)

  • An injury to Broca’s area would likely impair language production, consistent with language localization findings

  • Comparative anatomy (monkey vs rat cortex) informs translational research and the validity of animal models for human neurological conditions

  • Ethical considerations: brain injury studies (historical and modern) raise questions about consent, animal research, and the welfare of research subjects