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Neuroscience Fundamentals Flashcards

Divisions of the Nervous System (NS)

  • Central Nervous System (CNS)

    • Comprises the brain, brainstem, cerebellum, and spinal cord.

  • Peripheral Nervous System (PNS)

    • Somatic System (Voluntary)

      • Somatic sensory components.

      • Skeletomotor components.

    • Autonomic System (Involuntary)

      • Parasympathetic division.

      • Sympathetic division.

      • Enteric nervous system (NS of the gut).

Major Segments and Components of the CNS

  • CNS Major Segments

    • Spinal Cord

    • Brainstem

    • Cerebellum

    • Cerebrum

  • Detailed Brain Anatomy (Mid-sagittal & Lateral Views)

    • Cerebrum Components

      • Frontal lobe

      • Parietal lobe

      • Temporal lobe

      • Occipital lobe

      • Cingulate gyrus

      • Cingulate sulcus

      • Corpus callosum

      • Parieto-occipital sulcus

      • Calcarine sulcus

    • Other Structures

      • Midbrain

      • Pituitary gland

      • Pons

      • Medulla

      • Cerebellum

  • Overall Function of CNS Segments

    • Cerebral hemispheres, diencephalon, cerebellum, brainstem, and spinal cord collectively operate to analyze and integrate sensory and motor information.

  • CNS Overview (Subcortical View)

    • Brain

      • Cerebrum

      • Cerebellum

      • Subcortical Nuclei

    • Brainstem

      • Mesencephalon

      • Pons

      • Medulla

    • Spinal Cord

      • Cervical

      • Thoracic

      • Lumbar

      • Sacral

Peripheral Nervous System (PNS) Components

  • Sensory Components

    • Sensory ganglia

    • Sensory nerves

    • Sensory receptors, located at the surface and within the body.

    • Process: Information generated from the internal and external environment (generating sensory info) travels back to the brain to initiate the sensory-motor cycle again.

  • Motor Components

    • Visceral Motor System (Involuntary)

      • Includes sympathetic, parasympathetic, and enteric divisions.

      • Comprises autonomic ganglia and associated nerves.

      • Effectors: Smooth muscles, cardiac muscles, and glands.

      • Outcome: Expression of motor output to these effectors.

    • Somatic Motor System (Voluntary)

      • Comprises motor nerves that project to skeletal muscle.

      • Used during voluntary actions.

      • Effectors: Skeletal (striated) muscles.

Spinal Cord

  • Chief Function: Serves as the primary input-output pathway for sensory and motor signals between the body (below the neck) and the nervous system.

  • Signal Transmission: Facilitates the transmission of ascending (sensory) and descending (motor) signals along segregated pathways.

  • Afferents (Sensory Signals)

    • Mediate general sensations such as touch, pressure, vibrations, motions, and pain from the limbs, neck, and trunk.

    • These signals ascend through the spinal cord's white matter en-route to the brain.

  • Efferents (Motor Signals)

    • Carry motor signals for voluntary movements in the limbs, neck, and trunk.

    • These signals originate in the brain and descend through the spinal cord's white matter to reach skeletal muscles.

  • Regional Naming: The spinal cord takes on regional names and functions based on its segment (Cervical, Thoracic, Lumbar, Sacral).

  • Cauda Equina: Literally means