(W4) Ch 8 The body in health and illness

Hindbrain

medulla oblongata: blood pressure, heart rate, respiration

reticular formation: attention, wakefulness

pons and cerebellum: integrating reflexes and automatic behavior

midbrain

reticular system, sensory and motor correlation centres: integrating reflexes and automatic behavior

forebrain

influences mood and behavior

thalamus: attention, memory, central hub

hypothalamus: hunger, sexual arousal, thirst

limbic system: hippocampus, fornix, mammillary bodeis, thalamus, cingulate cortex, hippocampus, amygdala

cerebrum

basal ganglia: complex motor coordination

cortex: 4 lobes, 2 hemispheres, connected by corpus callosum

frontal lobe: executive functions, motivation, connections to limbic system

temporal lobe: left temproal lobe=language, right= visuospatial skills (in right handed ppl), smell, hearing, integrating sense, memory, linking emotions to memory

occipital lobe: visual perception

parietal lobe: integration of sensory information

symptoms possible after stroke

Autonomic nervous system

monitors and if needed takes control over activity level of key organs and organ systems so that it is all coordinated

hypothalamus receives info from many diff sources :

• reticular formation - temperature

• optic nerve (light and dark)

• hypothalamus itself - ion balance and temperature of the blood

• links to cortex and limbic systems - response to psych demands possible

ANS consists of:

sympathetic nervous system (fight/flight): activation and arousal

Parasympathetic Nervous System (rest/recover): relaxation

ANS overview

ANS contid

both systems start in the medulla oblongata

pass down the spinal cord to various synapses

there they link to a second series of nerves which are linked to all key body organs

sympathetic sys:

• neurotransmitter involved at the synapse betw spinal cord nerves and nerve of target organ is acetylcholine

• activity at the synapse betw second nerve and end organ mainly is NT noradrenaline and to lesser extent adrenaline (also called norephinephrine and epinephrine)

parasympathetic sys:

• Acetylcholine at both synapses

ENDOCRINE PROCESSES»

activity initiated by sympathetic nervous system is short lived

longer term effects on arousal are done by endocrine glands

adrenal glands

situated above the kidneys, extend SNS activity

two functional areas:

1. adrenal medulla activated by the SNS causing it to secrete the hormone version of noradrenaline (SNS adrenal medulla xis/ SAM axis)

2. pituitary gland is stimulated by the hypothalamus and releases hormones into the blood incl ACTH, ACTH controls the release of corticosteroids (anti-inflammatory hormones incl cortisol that are made naturally in the body) in the adrenal cortex. cortisol is a stress hormone that incr availability of energy stores and fat as fuel for long periods of exercise. supresses inflammatory response of damaged tissue (Hypothalamus Pituitary Adrenal axis /HPA axis)

see figure p63

the immune system