Ch. 2: The Anatomy and Evolution of the Nervous System

dorsal

top

rostral

front

caudal

back

ventral

bottom

coronal (frontal) section

mid-sagittal (medial) section

horizontal section

lateral

outer side in coronal and horizontal sections

meninges

membranes that envelope the CNS

• dura mater

• arachnoid membrane

• pia mater

cerebrospinal fluid (CSF)

• clear, colorless bodily fluid found in brain and spine (CNS)

  • produced in the choroid plexus

• flows from ventricles through the subarachnoid space, then reabsorbed into blood stream

Roles:

• mechanical protection (cushion)

• chemical stability/clears waste (pee)

• maintains proper intracranial pressure

vascular system

blood vessels:

• vertebral artery (front neck)

• common carotid artery (back neck)

roles:

• provides nutrients and oxygen

• carries away wasts

blood brain barrier (BBB)

prevents bad things from going to the brain

• issue: oral medicine needs to be small enough to pass through barrier

spinal cord tracts

tracts: carry sensory and motor info. to/from the brain

spinal cord anatomy

dorsal = sensory

ventral = motor

• hindbrain

• medulla

• pons

• cerebellum

medulla

• in hindbrain

• connects the higher levels of the brain to the spinal cord

• hosts the vagus nerve

• contains the cardiac, respiratory, vomiting and vasomotor center (autonomic involuntary functions)

pons

• in hindbrain

• “bridge”

• relays message from the cortex and the cerebellum

• regulates sleep and basic functions (breathing)

cerebellum

• in hindbrain

• coordinates movements (find adjustments based on sensory information)

• may be involved in complex behaviors (social behaviors)

• midbrain

• tectum

• tegmentum

tectum

• in midbrain

• dorsal position: auditory and visual processing

tegmentum

• in midbrain

• ventral position: many unconscious homeostatic and reflexive pathways

• ventral tegmental area (reward)

• red nucleus (motor coordination)

• substantia nigra (movement)

  • main region involved with Parkinson’s

    • as neurons die, you lose control of movement

forebrain

diencephalon:

• thalamus

• hypothalamus

telencephalon:

• cortex

• basal ganglia

• hippocampus

• amygdala

thalamus

• forebrain - diencephalon

• sensory center

hypothalamus

• forebrain - diencephalon

• regulatory center

  • regulation of hormones and homeostasis

    • e.g.) eating

diencephalon

• thalamus

• hypothalamus

telencephalon

• cortex

• basal ganglia

• hippocampus

• amygdala

cerebral cortex

• forebrain - telencephalon

• outermost layered structure of neural tissue of the brain

• 6 layers

• 2 hemispheres

• 4 lobes

  • frontal lobe: executive functions; emotional regulation

  • parietal lobe: somatosensory cortex

  • occipital lobe: visual cortex

  • temporal lobe: visual memory; auditory cortex

• basal ganglia

• forebrain - telencephalon

• motor control: planning, movement, reward

• receives info. from cortex, sends info. to thalamus

limbic system

emotions and memory

• forebrain - telencephalon

• hippocampus

• amygdala

hippocampus

• forebrain - telencephalon

• part of limbic system

• memory

amygdala

• forebrain - telencephalon

• part of limbic system

• emotions

peripheral nervous system (PNS)

ganglia and nerves connecting CNS to muscles, organs and skin

somatic nervous system

• PNS

• brings sensory input to the brain and spinal cord and returns commands to muscles

• cranial nerves =12 pairs

• spinal nerves = 31 pairs

autonomic nervous system

directs the activity of the glands, organs and smooth muscles

• PNS

• sympathetic system

  • fight or flight

• parasympathetic system

  • rest and digest