Biopsychology
The nervous system and the endocrine system -
The central nervous system is made up of the brain and the spinal cord
whilst the peripheral nervous system relays messages from the
environment to the CNS vias sensory neurones and from the CNS to
effectors via motor neurones.
Central nervous system, brain, and spine. Brain stem regulates automatic
functions necessary for life, neurones pass through brain stem,
communications between brain and body. Cerebellum area for motor
skills and balance and coordinate muscles to allow pressure movements.
Cerebrum divided into four lobes: frontal (thought and speech), occipital
(processing of visual images), parietal (processes sensory information),
temporal (hearing, memory, and comprehension of language).
PNS is further subdivided into the autonomic (involuntary movements,
e.g., heart rate) and the somatic nervous system (information from
sensory receptors of 5 sense and results in effectors being stimulated by
CNS via motor neurones. Autonomic divided into parasympathetic and
sympathetic. Crucial in producing the physiological arousal needed to
maintain fight or flight. Parasympathetic increases heart rate, breathing
rate, vasoconstriction.
Endocrine system is main chemical messenger if the body hormones
secreted into bloodstream from gland and transported towards target
cells in blood, complementary receptors. Pituitary gland, master gland,
controls release of hormones from all other glands in body e.g., adrenal
gland releases adrenaline which creates the physiological arousal for fight
or flight.
Fight or flight response –
Sympathomedullary – higher brain functions become aware of stressor in
the environment, alerts the hypothalamus which triggers levels of activity
in the sympathetic branch of ANS, alerts the adrenal medulla in gland to
, secrete adrenaline/noradrenaline. Breathing increase, saliva production,
vasoconstriction ready for fight or flight.
Pituitary adrenal – higher brain functions signal hypothalamus which
alerts anterior pituitary which secretes SCTH into the blood stream to the
adrenal cortex which secretes cortisol, immunosuppression, high energy.
Nervous vs endocrine – hormones/neurons, chemical
messengers/electrical impulses, slow/fast, long lasting/short lived.
A03 – tend and befriend - Taylor differences between genders when
dealing with stress, oxytocin in women high. Evolutionary hangover –
society change develops much faster than evolution, things that one
stress aren’t the same anymore, modern stressors don’t warrant the fight
or flight response. Freeze response – model doesn’t account for the
freeze response, tendency to stand still and remain quiet when
something poses a threat. Cooperative – also doesn’t account for people
who run towards the danger, motivated to help others rather than fight
or run away.
Neurones and synaptic transmission –
Relay neurones – a neuron found in the CNS which allows for
communication between sensory and motor neurones
Sensory neurones – a neurone that transmits sensory information from
the environment to an interneuron after converting it to electrical
activity.
Motor neurone – a type of neuron that activates an effector organ
(muscles, glands, organs).
Structure of neuron – dendrites, nucleus, myelin sheath, axon, nodes of
ranvier, terminal button
Stimulus – response – sensory neuron – relay = CNS = relay – motor
neuron – effector – response
Synaptic transmission is a method of neurons communicating with each
other, relaying information to the CNS across sensory neurons and
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