Paper 2 : Neuropsychology

• What is the function of the CNS? - Centre of all our conscious awareness & where all decision making takes place - Brain stem - connects brain and spinal cord. Control basic functions e.g regulating sleep and consciousness , directing reflex responses
• What is the function of the PNS? "- ""around the outside"" - Sends messages of Information from ouside world to CNS - Recives messages from CNS - These messages are sent via neurons"
• What is the function of the ANS? - Automatic (Involuntarily) functions - E.g breathing, heart rate, sweating, digestion - If were to consciously direct these activities they may not happen
• What is the function of the SNS? - Sends information from the brain to the muscles - Controls voluntary movement of muscles - Takes information from sensory organs
• What is the function of the sympathetic nervous system? - Works in opposition to the Parasympathetic nervous system - Represents a state of psychological arousal = breathing rate increases, sweating, heart beats rapidly - Makes our body prepare for the fight or flight response
• What is the function of the parasympathetic nervous system? - Counteracts with actions of sympathetic nervous system - Produces the rest and digest response = returns body to normal resting state once threat has gone
• What is the function of homeostasis as one of the actions of the ANS? - Process in which the body maintains a constanst and balanced state - e.g lvls of CO2 in blood being carefully controlled by regular breathing - e.g body temp of 37 C
• Define the fight or flight response Immediate physiological / Automatic response to real or perceived threat
• What hormone is involved in the fight or flight response? Stress hormone - Adrenaline
• Define Hypothalamus Small structure in the brain that controls many important functions e.g hunger, thrist, body temp and fight or flight
• What is James-Lange's theory of emotion about? He proposed that bodily changes come first and form the basis of an emotional experience
• Summarise James-Lange's theory of emotion EVENT --> AROUSAL --> INTERPRETATION --> EMOTION
• Psychological arousal first - An event (a stressor or threat in environment ) causes this : hypothalamus activates sympathetic division of ANS - Release of adrenaline creating arousal = experienced as increase in bodily activity e.g heart rate, blood pressure
• Emotion afterwards - Brain interprets the psychological activity which causes an emotion - e.g sense of fear, excitement
• No psychological changes = no emotion - If there are no psychological changes, or are not noticed = no emotion experienced - e.g presenting in front of class and your heart rate doesn't increase, then you would probably conclude that you were not nervous
• Evaluate a strength of James-Lange's theory or emotion - Real - life examples of emotions following psychological arousal - Emotional states seem to follow psychological arousal in cases such as phobias or panic disorders - e.g fall and trip --> arousal --> interprets --> anxiety or embarrassment = leads to them avoiding public situations as an association has been formed between situation and the emotion - Suggests that emotion and avoidance occur as a result of psychological reaction
• Evaluate a weakness of James-Lange's theory of emotion - Two - factor theory suggests that emotion may be more complex - The two-factor theory states that we need psychological arousal and social cues to correctly label the emotion we are feeling - e.g in a dark alleyway = heart racing = fear - kissing partner = heart racing = excitement - Theory does not explain how a person decides what emotion they are experiencing
• What are neurons? Nerve cells that communicate messages through chemical and electrical signals throughout nervous system.
• What are the types of neurons? - Sensory - Relay - Motor
• Sensory neuron - carry messages - PNS To CNS - Long dendrites and short axons
• Relay neuron - connect sensory & motor neuron as they do not connect directly - connect to other relay neurons - Short dendrites and short axons
• Motor neuron - carry messages - CNS to effectors e.g muscles and glands - Short dendrites and long axons
• Structure of neuron - Cell body (soma) - Dendrites - Axons covered in myelin sheath - Myelin sheath has gaps called Node of Ranvier - Terminal button
• Function of cell body (soma) - Nucleus = contains genetic material of each neuron
• Function of Dendrite - Carry electrical signals from neighbouring neurons to cell body
• Function of axon - Carries electrical signal away from cell body and down length of neuron
• Function of myelin sheath - Protects axon as it covers it - Speeds up the electrical signal - Has gaps called Nodes of Raniver - makes signal go even faster as it jumps across each gap
• Function of terminal buttons - Communicate with the next neuron in the chain - Across a gap called synaptic cleft
• How do neurons fire? - Electrical transmission - When neuron is in a resting state, inside of cell is negatively charged compared to outside - When fires = electrical charge changes for split second causing action potential
• Define synapse The small gap between two neurons that allows signals to pass between them.
• Define synaptic cleft The gap between the presynaptic neuron and postsynaptic neuron in which the impulse is transmitted by a neurotransmitter
• Release of neurotransmitters Electrical signal arrives at the presynaptic neuron's terminal button. (Tiny sacs) vesicles, filled with neurotransmitters, are located at the terminal button. The electrical signal triggers the release of neurotransmitter molecules from the vesicles. Neurotransmitters travel across the synaptic cleft to reach the postsynaptic neuron.
• Reuptake of neurotransmitters - Neurotransmitter crosses synaptic cleft. - Binds to receptor sites on postsynaptic neuron's dendrites. - Chemical message converted to back into electrical impulse. - Electrical impulse travels down the postsynaptic neuron - Remaining neurotransmitter broken by enzymes and reabsorbed by presynaptic neuron
• Define Inhibition - A neurotransmitter binding with a receptor on the postsynaptic neuron and decreasing the likelihood that the next neuron will fire an electrical impulse. - Keeps next cell from firing
• Define Exicitation - A neurotransmitter binding with a receptor on the postsynaptic neuron and increasing the likelihood that the next neuron will fire an electrical impulse - Causes next cell to fire
• Excitation and Inhibition - Transmitter can have an excitatory or inhibitory effect on next neuron in chain - Adrenaline (neurotransmitter) = increases + charge of postsynaptic neuron = exicitation = more likely to fire - Serotonin = increases - charge of postsynaptic neuron = inhibition = less likey to fire
• Summation - One neuron may recive 1000s of signals from other neurons withn a network of neurons - More exicitatory signals than inhibitory signals - cause neuron to fire and an electrial impulse will be created
• Brain - Divided into 2 halves, hemispheres - Top surface layer is called cerebral cortex, divided into 4 lobes
• What are the four lobes of the brain? - Frontal lobe - Temporal lobe - Parietal lobe - Occipitial lobe
• What is the function of the frontal lobe? - At the front of the brain - Controls thinking, planning - Includes motor area - controls movement - Contains Broca's area (language)