Brain and neuropsychology Flashcards
nervous system functions
1) to collect and respond to sensory information from the environment.
2) to control the working of different organs and cells in the body
Central nervous system consists of:
brain and the spinal cord
Peripheral nervous system consists of:
Somatic and autonomic nervous system
Autonomic nervous system splits into:
the parasympathetic and sympathetic nervous sytem
function of the central nervous sytem
coordinates incoming information and uses the brain to make decisions about movements or how to act.
- store of all our knowledge (memory)
function of the peripheral nervous system
Supports the actions of the CNS, recieving emssages from the CNS and sending messages to it.
Autonomic nervous system function
Network of special nerves which takes info to and from the CNS
- Cannot control it.
- Coordinates important life functions such as breathing, heart rate and digestion.
- controls homeostasis (where body maintains stable internal environment), like level of CO2 or body temp
Somatic nervous system function
Passes sensory information to the CNS using sensory neurons and transports info from the CNS to muscles using motor neurons.
- voluntary system which we can control, leading to movement
- is responsible for one involuntary action: form of reflex
(OVERALL ALLOWS FEELING AND MOVEMENT)
Sympathetic nervous system function
Is the accelerator that leads to physiological arousal,
Increases heart rate, breathing rate, sweat rate to prepare the body for fight or flight
Flight or fight response stages
- the hypothalamus detects a stressor
- Sends a nerve impulse to the adrenal glands
- adrenaline is released from adrenal glands
- adrenaline causes the heart to beat faster, pupils dilate, breath faster, stops digestion and saliva production
Results in muscles having a better supply of oxygen and helps us have the energy for fighting or flighting
Parasympathetic function
returns the body to resting state by doing the opposite of the effects of the sympathetic NS - acts as a brake.
Decreases bpm, improves blood supply for digestion and there is a higher production of saliva
Reflex arc
sensory neurone –> relay neurone –> motor neurone –> effector –> response
reflex arc in terms of touching/being near a hot surface
Heat is sensed on the surface of the SKIN. This is detected by a SENSORY neurone. which transports the information to the CNS. When it reaches the SPINAL CORD it connects with a relay neuron which passes the information to a MOTOR neurone.
The motor nueron is connected to an EFFECTOR or muscle which is then instructed to ACT (e.g. removing the hand from the heat)
how are messages sent to form reponses (SNS)
Stimulus –> receptor (sense organ) –> CNS –> effector (muscle/glands) –> response
James lange theory
EVENT –> AROUSAL –> INTERPRETATION –> EMOTION
emotion are caused by the way we interpret bodily reactions
Example of james lange theory
Bear in forest:
1. seeing the bear would cause the SNS to be activated
2. muscles would tense and heart will pound
3. After the changes have occured, the person would interpret this as fear (emotion)
no physical changes meaning (in terms of James-Lange theory)
No physical changes = no emotion. E.g. you gave a speech to an audience and you didn’t sweat or have an increase heart rate, you would feel as though you aren’t nervous
Advantages of James-Lange theory
Real life examples (application). Emotional states seem to follow arousal in phobis or panic disorders. E.g. a person may trip in public which leads to them feeling anxiety/embarrasement. Leading them to avoiding public situations as a link has formed between the situation and the emotion.
Disadvantages of James lange theory
Opposing theories: Cannon bard theory: proposes that emotion and arousal occur simultaneously. Feeling embarassed at the same time we blush. Also argued that not all physiological changes lead to an emotion (like exercising). Schatner and Singers theory propose that emotion does come after arousal, however, it says we need social cues to correctly label the emotion we are feeling. Heart racing in dark alleyway while being followed = fear, whereas heart racing during kissing = excitment. JT theory is reductionist.
Evidence for the existence of distinct physiological patterns corresponding to each emotion is inconclusive. Many emotions share similiar physiological responses.
Neurone function
Send electrical and chemical signals to one another to communicate
Sensory neurone
carries messages from the PNS to the CNS.
- long dendrites and short axons
Relay neurone
connects sensory neurones to motor neurones as well as other relay neurones.
- short dendrites and short axons
Motor neurone
carry messages from the CNS to effectors in our body.
- Short dendrites and long axons
synapse
a junction between two neurones
Synaptic transmission
the process of a presynaptic neurone converting an electrical signal to a chemical signal which is then detected by a post synaptic neurone.
(How info is passed on in neural systems)
Neurotransmitters
the chemical molecules released by neurones and detected by receptor sites
- either excitory or inhibitory
neurotrasmitter release
the detection of an action potential (electrical signal) causes vesicles to merge with the cell membrane, releasing neuro-tramitters. These are detected by the recpetors on the postsynaptic neurone.
Neurotransmitter reuptake
after detection by receptors neurotransmitters are taken back into the presynaptic cell via transport proteins. vesicles reform ready for the neurone to fire again.
Excitation
some neurotransmitters are excitory, on detection they make the post-synaptic cell more likely to fire
inhibition
some neurotransmitters are inhibitory, on detection they make the post-synpatic cell less likely to fire
Summation
determines if a neurone will fire by working out if there are more excitatory than inhibitory messages
motor cortex
(Frontal lobe) controls deliberate movement via motor neurones
Somatosensory cortex
(Parietal lobe) Recieves and processes sensory info from around the body
auditory cortex
(temporal lobe) controls our ability to percieve sound and processes spoken words
visual cortex
(occipital lobe) controls our abilitity to percieve things visually
brocas area
(left part of the frontal lobe) Speech production. Aphasia would be loss of speech.
Wernickes area
(left part of temporal lobe) Speech comprehension. Aphasia would be a loss of understanding speech.
frontal lboe
controls thinking and planning
parietal lobe
controls sensory perception. e.g. the five senses
occipital lobe
deals with vision - has the retina
temporal lobe
processing auditory information
contralateral
each hemisphere controls opposite sides
Tulvings gold scan study aim
to determine the location for semantic and episodic memory
Tulvings gold study procedure
6 ppt (volunteer sampling)
Ppts were injected with a gold isotope which spreads into the brain to which areas were active - PET scan. 8 trials - 4 S and 4 E. Repeated measures. Ppts were told to recall childhood and historical facts.
Tulvings gold study results
3 ppts gave inconclusive results and were discounted. 3 showed a clear difference in blood flow when recalling S & E memories,
E = frontal and temporal lobe
S = parietal and occipital lobes
Tulvings gold study evaluation
(+) PET scan is an objective method of assessment and no subjunctive interpration is required - factual
(+) ppl cannot fake what their brains are doing = less demand characteristics
(-) only 3 ppt showed differences in blood flow - not generalisable
(-) E and S are very similar, reason why the results were inconclusive
