4.2.2 Biopsychology🧬 Flashcards
what two parts is the nervous system broken down into
central nervous system (CNS) and peripheral nervous system (PNS)
what is the nervous system
the nervous system is a body wide system of nerve cells that collects information from the world , processes this information then takes action by directing body organs and muscles via the transmission of electrochemical messages. It is broken down into two parts
what is the central nervous system
the central nervous system is responsible for complex processing , CNS contains brain and spinal cord .
what is the role of the brain in the central nervous system
the brain is the centre of all conscious awareness e.g our cerebral cortex is the outer layer , it is highy developed and distinguishes our higher mental functions.
what is the role of the spinal cord in the central nervous system
the spinal cord receives and transmits information , some reflex processing, spinal cord is an extension of the brain and is responsible for reflex actions.
what is the peripheral nervous system
it contains a body wide network of messenger neurons , sensory neurons (afferent) To the CNS , and motor neurons (efferent) neurons away from the CNS. The peripheral nervous system contains two processes.
what are the two parts in the peripheral nervous system
autonomic system and somatic nervous system
what is the somatic nervous system
the somatic nervous system is a nervous system which controls voluntary movement e.g through skeletal muscles. It controls muscle movement and receives information from sensory receptors. It is under CONSCIOUS control
what are sensory receptors
sensory receptors are a structured that reacts to a physical stimulus in the environment
what is the autonomic nervous system
nervous system which controls involuntary movement , it governs vital functions in the body e.g breathing and digestion . Controls actions of internal organs and groups , Involuntary system - NOT UNDER CONSCIOUS CONTROL.
It is broken down into two processes which work together to regulate internal environment
what two parts is the autonomic nervous system broken down into
sympathetic and parasympathetic
what is the sympathetic nervous system
it’s part of the autonomic nervous system it increases bodily activities, Releases noradrenaline It activates during times of stress response (fight or flight).
what is the parasympathetic nervous system
it decreases bodily actuvities , releases or acetylcholine . Activates in rest . it’s role is to regulate body and return us to a normal resting state.
what is homeostasis
regulation of internal environment. in regular conditions there is a balance between sympathetic and parasympathetic nervous systems . This is a state or homeostasis
what are the three types of neurons
sensory neurons , motor neurons , relay neurons
what is the function of a sensory neuron
they convert signals from the external environment into corresponding internal stimuli .They carry information from the peripheral nervous system to the central nervous system.
what are the features of a sensory neuron
short axons
long dendrites
cell body outside
has myelin sheath
what is the function of a relay neuron
they connect neurons to the motor neurone or other relay neurons. They receive messages from the sensory neurons and pass messages to either other interconnecting neurons or to motor neurons
what are the feature of a relay neuron
short axon
short dendrites
cell body inside neuron
no myelin sheath
what is the function of motor neurons
they carry electrical impulses from the brain and spinal cord (CNS) to the organs and muscles in the body (PNS)
what are the features of motor neurons
long axons
short dendrites
cell body inside the neuron
has myelin sheath
what is synaptic transmission
synaptic transmission is the process by which one neuron communicates with another
explain the process of synaptic transmission
1) nerve impulse travels down an axon (electrical transmission) as an electrical impulse.
2) once the nerve impulse reaches the presynaptic nerve terminal it must cross the gap between presynaptic neuron and post synaptic neuron.
3) at the end of the neuron (in the axon terminal) are synaptic vesicles which contain chemical messengers (neurotransmitters)
4) when the electrical impulse reaches these synaptic vesicles they fire the neurotransmitters across the synaptic gap.
5) the neurotransmitter then binds to receptor sites on the dendrite of the adjacent neuron. If successful the neurotransmitter it is taken up by the post synaptic neuron
explain the process of electrical transmission
- when in a resting state the cells inside a neuron are negatively charged.
when a neuron is activated by an impulse the inside of the cell becomes positively charged for a short period of time causing an action potential to occur.
this creates an electrical impulse that travels doen the axon towards the edge of the neuron , this action potential is only created by excitatory neurons
what are excitatory neurontransmitters
excitatory neurotransmitters such as noradrenaline bind with receptors on a post synaptic neuron and cause them to leg in positive ions into the cell. By making the cell less negative it means that the neuron is more likely to fire and pass on the electrical impluse
what are inhibitory neurotransmitters
inhibitory neurotransmitters prevent an action potential being created , e.g serotonin . Inhibitory neurotransmitters bind to a post synaptic neuron allowing negative ions into the neuron , making it even more negative , which means the neuron is less likely to fire and pass on the electrical impulse.
what is localisation of function
the theory that different areas of the brain are responsible for different behaviours , processes or activities. It therefore follows that if an area of the brain becomes damaged through illness or injury, the function associated with that area area will also be effected
what are the 6 examples of localisation of function
motor area somatosensory area visual area auditory area broca’s area wernickes area
what is the cerebral cortex
the brain is divided into two hemispheres, left and right, which is surrounded by the cerebral cortex which covers the inner parts of the brain . The correct is about 3mm thick.
what are the four lobes in the brain
frontal , parietal , occipital , temporal
what is the structure of lobes in the brain
briefly explain phineas gage in relation to localisation of function
Whilst working on the railroad in 1848 phineas gage had a metre length pole hurled through Gage’s left cheek passing behind his left eye and exiting his skull from the top of his head taking a proportion of his brain with it (most of his frontal lobe).
gage survived but the damage to his brain left a mask on his personality he went from being calm and reserved to somebody who was quick tempered and rude
This acts as landmark case which suggests the frontal lobe may be responsible for regulating mood
what are strength of localisation of function - brain scanning
-There is brain scanning evidence to support that functions are localised. Peterson et al used brain scans - showed wernickes area was active during a listening task , Broca’s area was active during a reading task. supports the idea different parts of the brain have different functions
what are strength of localisation of function - neurosurgical evidence
there is neurosurgical evidence to support that functions are localised . Dougherty reported 44 OCD patients who had undergone a cingulotomy. A post surgical follow up after 32 weeks showed 1/3 had a successful response to the surgery and 14% a partial repsonse. Success of procedures such as this suggest that symptoms and behaviours associated with serious mental disorders are localised.