The Nervous System Flashcards
What are the two sub systems of the nervous system?
Central Nervous System & Peripheral Nervous System
What does the Central Nervous System consist of?
The Brain: Provides conscious awareness and is involved in all psychological processes
The Spinal Cord: Transfers messages to and from the brain and the rest of the body.
What are the two parts of the peripheral nervous system?
The Somatic & Autonomic Nervous System
What are the two parts of the Autonomic nervous System
Sympathetic & Parasympathetic Nervous System
What is the role of the somatic nervous system
It is the part of the peripheral nervous system that carries sensory and motor info to and from the Central Nervous System (CNS)
What is the role of the Autonomic Nervous System?
It governs the brains involuntary (automatic) activities such as a stress, breathing, heart rate etc
What is the role of the Sympathetic nervous System
Arouses the body and helps us to deal with emergencies (stressful situations)
What is the role of the parasympathetic nervous system?
Relaxes the body once the emergency has passed
Explain the process of Fight or Flight
The hypothalamus sends a signal to the adrenal medulla which produces adrenaline.
This causes an increased heart rate, increased blood pressure which in turn makes the mouth becomes dry, digestion stop in order for the body to become ready for fight or flight.
Evaluate Fight or Flight
Contradictory research
Gray suggests the first response to danger is to avoid confrontation altogether which is demonstrated by a freeze response
Evaluate Fight or Flight
Gender Differences
It has been argued that Fight or Flight response is typically a male response to danger and more recent research suggests that females adopt a tend and befriend response in stressful/dangerous situations.
What is the role of the adrenaline
A stressor in the environment which sends a signal to the hypothalamus.
This triggers the sympathetic nervous system which sends a signal to the adrenal medulla.
The adrenal medulla releases adrenaline into the bloodstream
Adrenaline causes psychological changes which help the body deal with the threat.
Once the threat has passed the parasympathetic nervous system is triggered and calms down the body’s response
Outline the structures and processes involved in synaptic transmission
A neutron at resting state is negatively charged but when it is activated by a stimulus. The inside of the cell becomes positively charged causing an action potential to occur
Electrical impulses travel through the pre synaptic neurons which triggers the release of neurotransmitter from tiny sacs called synaptic vesicles.
The neurotransmitters then travel through the synaptic cleft which is the gap between the pre synaptic neurons and post synaptic neurons.
The neurotransmitters either bind to the receptors at the post synaptic neurons, diffuse in the cycle or are taken back to the pre synaptic neurons. This is known as re- up take.
Describe excitatory and inhibitory neurotransmitters
If the neurotransmitter is excitatory e.g. adrenaline it causes the neighbouring neuron to become positively charged and is more likely to fire.
If the neurotransmitters is inhibitory e.g. Serotonin it causes the neighbouring neuron to be negatively charged making the post synaptic neuron less likely to fire.
