Psychology Exam Revision Flashcards
(171 cards)
Brain
Regulates and guides all other parts of the nervous system including:
- Initiates, responds and controls all bodily functions and actions. e.g. breathing
- Receiving and processing sensory information from the outside world via the senses and co-ordinating appropriate responses.
Spinal Cord
Spinal cord is the two-direction superhighway for all information/messages coming to (sensory - afferent) and leaving (motor - efferent) the brain.
These two pathways are called tracts.
Major Functions of Spinal Cord
Receives sensory information from the body (via the PNS) and transmit them to the brain up the spinal cord for processing.
Receives motor information from the brain and sends it to the relevant parts of the body (via the PNS) to control muscles, glands and internal organs so appropriate actions can be taken.
Initiating certain types of reflex responses that occur independently of the brain e.g. spinal reflex.
Peripheral Nervous System
Carries sensory information from the rest of the body to the CNS and motor information from the CNS to the rest of the body.
Somatic Nervous System
Consists of sensory and motor nerves connected to the CNS:
- Sensory (afferent neurons) – transmits sensory information received by the sensory receptors in the body such as eyes, TO the CNS.
- Motor (efferent neurons) – transmits impulses FROM the CNS to control any VOLUNTARY movements of the skeletal muscles (e.g. fingers, legs etc).
Autonomic Nervous System
Comprises of nerves that control the body’s AUTOMATIC, INVOLUNTARY functions.
It is mostly responsible for communication between the CNS and the body’s non-skeletal, visceral muscles as well as internal organs (such as the heart) and glands (such as adrenal glands) which carry out basic bodily functions necessary for basic survival.
Sympathetic Nervous System
Increases the responsiveness of many internal muscles (non-skeletal), organs and glands for significant physical activity, stress or when threatened.
As the body prepares for action:
- Adrenaline is released into bloodstream
- Heart rate, blood pressure, respiration rate increase
- Saliva production, stomach contractions decrease
- Pupils dilate
- Blood flow to skeletal muscles increase
- Blood sugar levels increase
Parasympathetic Nervous System
Decreases the responsiveness of the muscles, organs and glands thereby conserving our energy and returning our internal systems to the balanced level of functioning.
2 functions;
- It returns the body to a calm state by reversing the direction of the changes of the sympathetic nervous system once the threat has passed.
- It minimises energy use and keeps the internal body environment in a steady, balanced, homeostatic state of normal functioning.
Fight-Flight-Freeze Response
The “fight-flight-freeze response” is our body’s primitive, automatic, inborn response that prepares the body to “fight” or “flee” or “freeze” from perceived attack, harm or threat to our survival.
Neuron
Defined as an individual nerve cell that is specialised to receive, process and/or transmit information to other cells in the body.
Dendrites
Function
- They detect and receive information from other neurons.
- Each spine provides a site with receptors where a neuron can connect with and receive information from a neighbouring neuron.
Axon
Structure
- An axon is a single, tubelike, extension.
Function
- It transmits neural information away from the soma towards other neurons.
Myelin
Structure
- Myelin is a white, fatty substance surrounding the axon of a neuron.
Function
- It insulates the axon, and prevents interference from the activity of other nearby axons.
- It also allows for the rapid movement of the message along the axon without being interrupted or distorted.
Axon Terminals
Function
- They store and secrete neurotransmitters that are manufactured by the neuron and carries its chemical message to other neurons or cells.
Synaptic Transmission
When the neural impulse reaches the end of each axon, the terminal buttons releases chemicals called neurotransmitters.
The neuron that releases the neurotransmitter is called the presynaptic neuron, while the neuron that receives the neurotransmitter is called the postsynaptic neuron.
These receptors are specialised to receive specific neurotransmitters.
Any neurotransmitter that does not bind to a receptor successfully, is absorbed back into the terminal button by the presynaptic neuron in a process called reuptake.
Sometimes the neurotransmitter activates a neural impulse on the postsynaptic neuron. At other times, the neurotransmitter inhibits or prevents the postsynaptic neuron from firing.
Lock-and-Key Process
This process involves a neurotransmitter with a distinctive shape (a ‘key’) that precisely matches the shape of the receptor site (a ‘lock’) on the postsynaptic neuron where it will bind (‘unlock’) or attach to its receptors.
Excitatory Effect
An excitatory effect occurs when a neurotransmitter such as glutamate stimulates or activates a postsynaptic neuron to perform its functions.
This makes the postsynaptic neuron more likely to fire and enhance transmission.
Inhibitory Effect
An inhibitory effect occurs when a neurotransmitter such as GABA blocks or prevents a postsynaptic neuron from firing and therefore performing its functions.
Conscious Response
A reaction that involves awareness, controlled by the brain but also involves the somatic nervous system
Unconscious Response
A reaction that does not involve awareness and is often regulated by the autonomic nervous system and/or the spinal cord
Spinal Reflex- Unconscious Response
A spinal reflex is an unconscious, involuntary and automatically occurring response to certain stimuli initiated within the spinal cord and without any involvement of the brain.
involves somatic reactions such as when you jerk your bare foot up from the hot pavement
Steps in a Spinal Reflex
- Sensory neurons detect the stimuli and send the sensory information from the peripheral nervous system to the spinal cord in the central nervous system.
- The interneurons in the spinal cord receive the sensory information from the sensory neurons and connect with the motor neurons to initiate a response.
- The motor neurons carry the response back to the appropriate body part.
- The spinal reflex occurs which is an unconscious response that does not require any involvement of the brain.
- While the spinal reflex is occurring, the sensory information will be transmitted from the spinal cord to the brain for processing.
- The brain processes the sensory information for the sensation to be ‘felt’ which is a conscious response.
Parkinson’s Disease
Parkinson’s disease is a CNS neurodegenerative disorder characterised by both motor and non-motor symptoms.
It involves interference to nervous system functioning and is chronic meaning the symptoms persist for a long time and are recurring often beginning with stiffness and trembling in the limbs.
Motor Symptoms (Parkinson’s Disease)
- Tremors involving continuous, involuntary shaking of the body
- Muscle rigidity, whereby the muscles seem unable to relax and are tight, even when at rest.
- Postural instability, balance problems and gait (walking) disturbances