Neurobiology Flashcards
the brain
the co-ordinating centre of sensation and intellectual activity
continuous with the spinal cord
3 meninges
- pia mater: delicate, on brain surface
- dura mater: thick, lines skull and vertebral canal
- arachnoid mater: between others, cushions brain
meningitis
- inflammation of meninges
- viral is more common and mild
- bacterial is fatal
4 ventricles
connected cavities, continuous with the central cantal
into which cerebro-spinal fluid is secreted
- right/left lateral ventricles, 3rd and 4th ventricles
cerebro-spinal fluid
produced by cells lining the ventricles, resembles plasma
- supplies nutrients (glucose)
- supplies oxygen, carried in solution
- no RBCs = pale yellow colour
- contains antibodies and WBCs = role in resisting infection
hindbrain
sustains basic homeostatic functions
- cerebellum
- medulla oblongata
midbrain
contains nerve fibres linking hindbrain and forebrain
relays info for vision and hearing
forebrain
- limbic system: associated with learning, memory and emotion. Hippocampus, thalamus, hypothalamus.
- cerebrum: cerebral cortex
cerebellum
- convoluted surface, provides space for cell bodies for a large number of neurones
- co-ordinates voluntary tasks requiring fine motor control
- precision and timing in muscular activity
- contributes to equilibrium (balance) and maintaining posture
- learning motor skills
medulla oblongata
- controls basic functions; ventilation, maintaining blood pressure, regulation of heartbeat
- connects brain to spinal cord
- controls involuntary, autonomic functions
hippocampus
- interacts with cerebral cortex
- contributes to learning, reasoning, personality, and consolidating memory into a permanent store
thalamus
- relay centre
- sends/receives impulses to and from cerebrum
hypothalamus
- control general functions; body temp, blood solute conc, hunger, thirst, sleep
- main controlling region of autonomic nervous system
- links brain to endocrine system, through pituitary gland
cerebrum
- 2 hemispheres
- controls voluntary behaviour, learning, reasoning, personality, memory
- functions subconsciously
- source of intellectual function
- integrates sensory function
- initiates voluntary motor functions
- grey matter surrounds white matter
- higher cognitive function
autonomic nervous system
- part of peripheral
- controls automatic functions of the body by the antagonistic activity of the sympathetic / parasympathetic nervous systems
- continuous function of internal organs
- include reflex actions (sneeze, cough, swallow)
- regulated in hypothalamus
- decrease in blood pH or b.p = increased heart rate
sympathetic nervous system
- noradrenalin = excitatory = fight or flight
- increase heart rate, b.p, ventilation rate
- cell bodies in grey matter and ganglions
parasympathetic nervous system
- acetylcholine = inhibitory
- decreases heart rate, b.p, ventilation rate
- cell bodies in brain, spinal cord and close to target organs
steps of increasing heart rate (exercise)
- cardio-acceleratory centre stimulated
- nervous impulses travel along sympathetic nerve fibres to SAN
- noradrenalin released, binds to cell membrane receptors on SAN cells
- SAN’s electrical discharge increases in frequency
- heart rate increases
steps of decreasing heart rate (sleep)
- cardio-inhibitory centre stimulated
- nervous impulses travel along parasympathetic nerve fibres to SAN
- acetylcholine released, binds to cell membrane receptors on SAN cells
- SAN’s electrical discharge decreases in frequency
- heart rate decreases
corpus callosum
bundle of nerve fibres connecting the 2 cerebral hemispheres, allowing them to communicate
cerebral cortex
- outer 2-3mm of the cerebrum
- essential functions: memory, thinking, learning, reasoning, problem solving, emotion
- axons of neurons are deeper in the brain than cell bodies
- highly folded surface = large SA = large number of neurones
- motor, sensory, visual, auditory areas
frontal lobe of cerebrum
- personality
- site of reasoning, planning, emotion, problem solving
- dominant hemisphere includes Broca’s area (motor)
- motor cortex
temporal lobe of cerebrum
- processes complex stimuli (faces, scenes)
- auditory cortex = generates sound
- role in memory and learning
- left lobe contains Wernicke’s area (written / spoken speech)
- not lateralised = neither dominant
parietal lobe of cerebrum
- sense of taste
- role in visuo-spatial processing
- somatosensory cortex
- sensory processing
occipital lobe of cerebrum
- primary visual cortex
- associated with vision
