Biopsychology Flashcards
What is the nervous system?
Consists of the CNS and the PNS
What is the central nervous system?
Consists of the brain and the spinal cord and is the origin of all complex commands and decisions
What is the brain’s outer layer called?
The cerebral cortex
What is the peripheral nervous system?
It transmits messages, via neurons, to the CNS from the outside world and transmits messages from the CNS to muscles and glands in the body
What 2 systems can the PNS be divided into?
- Somatic nervous system
- Autonomic nervous system
What is the somatic nervous system?
- Transmits information from receptor cells in the sense organs to the CNS
- It also receives information from the CNS that directs muscles to act
What is the autonomic nervous system?
- Transmits information to and from the internal bodily organs
- It is ‘autonomic’ as the system operates involuntarily
- Governs the vital body functions
What 2 systems can the autonomic nervous system be divided into?
- Sympathetic
- Parasympathetic
What does antagonistic mean?
Work in opposition
Which nervous system is responsible for the ‘fight or flight’ response?
Sympathetic nervous system
What actions is the sympathetic nervous system responsible for?
- Slows digestion
- Inhibits saliva production
- Increases heart rate
- Stimulates glucose production
- Stimulates urination
- Dilates pupils
- Dilates bronchi
What actions is the parasympathetic nervous system responsible for?
- Increases digestion
- Increases saliva production
- Decreases heart rate
- Stimulates bile production
- Inhibits urination
- Constricts pupils
- Constricts bronchi
What is the endocrine system?
- One of the body’s major information systems that instructs glands to release hormones directly into the bloodstream.
- These hormones are carried towards target organs in the body.
What is a gland?
An organ in the body that synthesises substances such as hormones
What are hormones?
- Chemical substances that circulate in the bloodstream and only affect target organs.
- They are produced in large quantities but disappear quickly
- Their effects are very powerful.
What is adrenaline?
A hormone produced by the adrenal glands which is part of the human body’s immediate stress response system
What does adrenaline do?
Adrenaline has a strong effect on the cells of the cardiovascular system:
- Stimulating the heart rate
- Contracting blood vessels
- Dilating air passages
What is the normal resting state of the autonomic nervous system?
Parasympathetic state
What is the ‘rest and digest response’?
The parasympathetic system acts as a ‘brake’ and reduces the activities of the body that were increased by the actions of the sympathetic branch during the ‘flight or flight’ response
What is a neuron?
Nerve cells that process and transmit messages through electrical and chemical signals.
What are sensory neurons?
- These carry messages from the PNS to the CNS
- They have long dendrites and short axons.
What are relay neurons?
- These connect the sensory neurons to the motor or other relay neurons
- They have short dendrites and short axons.
What are motor neurons?
- These connect the CNS to the effectors such as muscles and glands
- They have short dendrites and long axons.
What is the nucleus?
The control centre of a cell, which contains the cell’s chromosomal DNA
What is a dendrite?
Receives the nerve impulse or signal from adjacent neurons
What is an axon?
Where the electrical signals pass along
What is a myelin sheath?
Insulates and protects the axon from external influences that might affect the transmission of the nerve impulse down the axon.
What are nodes of ranvier?
These speed up the transmission of the impulse by forcing it to ‘jump’.
What are terminal buttons?
Send signals to an adjacent cell
What is action potential?
- An action potential occurs when a neuron sends information down an axon, away from the cell body
- The action potential is an explosion of electrical activity - this means that some event (a stimulus) causes the resting potential to move forward.
How does a relfex arc work?
- Stimulus detected by the PNS conveyed along a sensory neuron
- Reaches the CNS where it connects with a relay neuron
- Message transferred to a motor neuron
- Message carried to an effector
Does a relfex arc involve the brain?
No
What does StoRM mean?
Sensory to Relay Motor
What can StoRM be used to remember?
How a reflex arc works
What is synaptic transmission?
The process by which neighbouring neurons communicate with each other by sending chemical messages across the gap (the synaptic cleft) that separates them.
What is a neurotransmitter?
Chemicals that are released from a synaptic vesicle into the synapse by neurons
What is excitation?
- When a neurotransmitter, such as adrenaline, increases the positive charge of the postsynaptic neuron.
- This increases the likelihood that the neuron will fire and pass on the electrical impulse.
What is inhibition?
- When a neurotransmitter makes the charge of the postsynaptic neuron more negative.
- This decreases the likelihood that the neuron will fire and pass on the electrical impulse.
What does normal brain function depend upon?
A regulated balance between excitatory and inhibitory influences
What is localisation of function?
The theory that different areas of the brain are responsible for different behaviours, processes or activities.
What is the motor area?
A region of the frontal lobe involved in regulating movement
What is the somatosensory?
An area of the parietal lobe that processes sensory information such as touch
What is the visual area?
A part of the optical lobe that receives and processes visual information.
What is the auditory area?
Located in the temporal lobe and concerned with the analysis of speech-based information
What is Broca’s area?
An area of the frontal lobe of the brain in the left hemisphere (in most people) responsible for speech production
What is Wernicke’s Area?
An area of the temporal lobe (encircling the auditory cortex) in the left hemisphere (in most people) responsible for language comprehension
How many hemispheres are there in the brain?
2 - Left and right
What are the 3 concentric layers of the brain?
- The Central Core
- The Limbic System
- The Cerebrum
What is the central core?
- Regulates homeostasis
- Regulates the endocrine system
- Includes the hypothalamus
What is the limbic system?
- Controls our emotions
- Around the central core, interconnected with the hypothalamus
- Contains the hippocampus