Bio Psych (approaches) Flashcards
What is the cerebral cortex?
The largest part of the brain and contains four lobes:
Frontal
Parietal
Occipital
Temporal
What is the frontal lobe?
Thought, planning, motivation and speech production
What is the parietal lobe?
Sensory (touch and movement) processing
What is the occipital lobe?
Visual processing
What is the temporal lobe?
Language comprehension, hearing and memory and can also help control our heart rate, blood pressure and breathing
What is the cerebellum?
Helps coordinate balance and fine muscle movements
The two hemispheres are joined by the corpus callosum, a bundle of nerve fibres that act as a key bridge between them, allowing communication
What is the nervous system?
Consist of the central nervous system and the peripheral nervous system
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 peripheral nervous system?
Sends information to the CNS from the outside world, and transmits messages from the CNS to muscles and glands in the body
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 automatic nervous system?
Transmits information to and from internal bodily organs. It is ‘automatic’ as the system operates involuntarily
The nervous system
What does the sympathetic NS do?
It is involved in processes that help us in emergencies, for example, the flight or fight response
It spurs the body into action in preparation to deal with (mainly) threats
What does the parasympathetic nervous system do?
Works to calm the body after arousal by the sympathetic NS
It calms the heart and lungs and allows normal ‘resting’ functions to resume (often referred to as rest and digest)
When is homeostasis created?
When the sympathetic and parasympathetic NS react
Their actions are mostly antagonistic
How much of the brain is made up by the cerebrum?
85%
What is contained in the diencephalon?
Thalamus
Hypothalamus
What is the thalamus?
Concerned with relaying sensory information from the brain stem to the cortex
What is the hypothalamus?
Controls basic functions such as hunger, thirst, sexual behaviour; and also controls the pituitary gland
What do the cerebral hemispheres control?
Higher level cognitive and emotional processes
What is the limbic system involved in?
Learning, memory and emotions
What is the basal ganglia involved in?
Motor activities and movement
What is the neocortex/cerebral cortex involved in?
Planning, problem solving, language, consciousness and personality
What is the spinal cord?
The spinal cord is an extension of the brain that is responsible for reflex actions. It allows the brain to monitor processes such as breathing and to control voluntary movements
What is the hindbrain?
A continuation of the spinal cord carrying on into the bottom of the brain - the brain stem - mainly composed of sensory and motor neurons. The cerebellum controls movement and motor co-ordination
What is the peripheral nervous system?
The portion of the nervous system that is outside the brain and spinal cord
The primary functions of the PNS is to connect the brain with the spinal cord to the rest of the body and external environment
It transmits information to and from the CNS
How does the PNS transmit information to and from the CNS?
This is accomplished through nerves that carry information from sensory receptors in the eyes, ears, skin, nose and tongue, as well as receptors and receptors in muscles, glands and other internal organs
What is the somatic nervous system?
SNS receives information from the senses and transmits it to the CNS. It also transmits information from the CNS to direct movement of muscles
What is the automatic nervous system?
Responsible for vital functions such as heartbeat, breathing and digestion
It transmits information from and to the internal body organs such as the liver and lungs
It operates automatically and involuntarily
The two main divisions of the automatic nervous system?
The sympathetic nervous system
The parasympathetic nervous system
Their actions are mostly antagonistic and they work in opposition of eachother
The opposing actions of the sympathetic and parasympathetic nervous system
What are hormones?
Chemical messengers secreted from structures (glands) in the body which pass through the bloodstream to cause changes in our body or behaviour. The network of glands in called the endocrine system
Hormones and effects
What is the fight or flight response?
A sequences of activity within the body that is triggered when the body prepares itself for defending or attacking or running away to safety
It involves two major systems:
The sympathomedullary pathway
The pituitary adrenal system
What is the sympathomedullary pathway?
Deals with acute (short-term and immediate) stressors such as personal attack
The pituitary-adrenal system?
Deals with chronic, long term, ongoing stressors such as a stressful job
What is the stress response?
Stress is experienced when a persons perceived environmental, social and/or physical demands exceed their perceived ability to cope
The stress response is hard wired into our brains and represents evolutionary adaption designed to increase organisms chances of survival in life threatening situations
Also known as the fight or flight response
How is the acute stress response produced?
The endocrine system
The endocrine system works alongside the nervous system to control vital functions in the body
The endocrine system acts more slowly but has very widespread effects
The main gland is the pituitary gland which controls the release of hormones from all other endocrine glands in the body
Hormones
Hormones are secreted into the bloodstream and affect any cell in the body that has a receptor for that particular hormone
They are produced by glands
The endocrine system (diagram)
What are neurons?
The basic building blocks of the nervous system
Nerve cells in the nervous system that transmit signals electrically a nd chemically
They are 80% located in the brain and provide the nervous system with a means of communication
A neuron
What are sensory neurons?
They carry messages from the PNS to the CNS, they have long dendrites and short axons
What are motor neurons?
These connect the CNS to effectors such as muscles and glands, they have short dendrites and long axons
How does a neuron work?
The cell body contains the nucleus
The dendrites extend from the cell body
They carry electrical impulses from other neurons toward the cell body
It is covered by a sheath of myelin, a fatty substance
What is the myelin sheath for?
To increase the speed at which impulses propagate
There are breaks between o.2 and 2mm in the sheath, these are called nodes of Ranvier
What is a relay neuron?
Carries messages from one part of the CNS to another
How do nerve impulses travel?
They ‘jump’ from node to node
Stimulus to response
How many neurons in the avergae human brain?
100 billion
How do neurons communicate?
Through synaptic transmission
Each neuron is separated from others by a small gap called a synapse. Signals within a neuron are transmitted electronically, however signals between neurons are transmitted chemically across the synapse
Chemical transmission
Electric transmission - firing of a neuron
When a neuron is in a resting state the inside of the cell is negatively charged compared to the outside. When a neuron is activated by a stimulus the inside of the cell becomes positively charged for a split second causing an action potential to occur. This creates an electrical impulse that travels down the axon towards the end of the neuron
Action potentials
When a neuron is not sending a signal it is ‘at rest’. When a neuron is at rest, the inside of the neuron is negative, relative to the outside
When a neuron is activated by a stimulus the inside of the cell becomes positively charged for a short time, this is the action potential/it creates the electrical impulse that travels through the axon to the end of the neuron
Excitatory and inhibitory effects
Some neurotransmitters act by making the neuron more negatively charged so less likely to fire. This is an inhibitory effect. This is the case for serotonin. Other neurotransmitters increase the positive charge so make the neuron more likely to fire. This is the excitatory effect. Adrenalin which is both a neurotransmitter and a hormone has an excitatory effect
