Lecture 3: Brain Flashcards
What parts of the brain are we interested in?
Limbic system Cerebral cortex Thalamus Hypothalamus Cerebellum Brain stem Spinal cord
Why is it important to study biological behaviour?
Our sensory processes make up our knowledge of our environment
We use our brain circuitry to think, reason and learn
We should understand what makes each person a unique individual
What does the limbic system do?
Regulates emotions and motivated behaviour
What does the cerebral cortex do?
It is involved in complex mental processes
What does the thalamus do?
Relays sensory info
What does the hypothalamus do?
Manages the body’s internal states
What does the cerebellum do?
Regulates coordinated movement (balance)
What does the brainstem do?
Sets the brain’s general alertness level and warning system
What does the spinal cord do?
It provides a pathway for neural fibres travelling to and from the brain
What are the two components of the autonomic nervous system and what are their roles?
Sympathetic nervous system: fight or flight response, emergency system
Parasympathetic nervous system: rest and digest, vegetative functions
The two systems act in opposition to control heart rate and act in concert to control sexual reflexes
What are the major neurotransmitters of focus in this course?
Glutamate GABA Dopamine Serotonin Acetyl hone Endorphins and enkephalins Epinephrine and norepinephrine
What does glutamate do?
Excitation of neurons throughout the nervous system
What does GABA do?
Inhibits neurons in the brain
What does dopamine do?
Involved in emotional arousal, pleasure, reward, voluntary movement and attention
What does serotonin do?
Sleep and emotional arousal, aggression, pain and mood regulation
What does acetylcholine do?
Learning and memory
What do endorphins and enkephalins do?
Pain relief and elevation of mood
What does epinephrine and norepinephrine do?
Emotional arousal, anxiety and fear
What are the steps of neural transmission?
Neurotransmitters in the axons of a neuron are stored in synaptic vesicles waiting to be stimulated by an action potential which causes their release
The action potential stimulates the release of neurotransmitters across the synapse
The neurotransmitters bind to the receptor sites on the dendrites of the next neuron, resulting in a change in potential
What are some further important functions of the cerebral cortex.
Provides flexible control of patterns of movement
Permits subtle discrimination among complex sensory patterns
Makes possible symbolic thinking
Organisation: primary and association areas
What happens if the frontal love is destroyed?
The ability to plan, limit impulses and reasoning are also destroyd
Which tasks are associated with the frontal lobe?
Skilled movements, emotion, behaviour, awareness, memory, smell
What tasks are associated with the temporal lobe?
Hearing
What tasks are associated with the parietal lobe?
Body sensations
What tasks are associated with the occipital lobe?
Visual recognition, vision
What tasks are associated with the cerebellum?
Balance and muscle coordination
What is between the frontal and parietal lobes?
Motor cortex (next to frontal lobe) and sensory cortex (between motor and parietal)
What is the endocrine system and what is its function?
A collection of glands that release hormones into the bloodstream (pituitary, thyroid, adrenal, ovaries/testes)
They send global messages to the bloodstream
What is the role of the pituitary gland?
Initiation of puberty
Regulation of endocrine glands
Sends growth hormones
Causes adrenal gland to release adrenaline,
thyroid to release thyroxin
Testes to release testosterone,
Ovaries to release progesterone and estrogens
What are the key facts regarding brain development?
At birth, brain is almost adult size
90% of adult brain weight is achieved by 2-6 years old
Advances: cerebellum, reticular function, corpus callosities
Cerebral cortex: consists of 85% brain weight and is the last to stop growing
What are the sensitive periods of development?
Stimulation vital during growth spurts (from infancy to early adulthood)
Experience wires a child’s brain growth
Under-stimulation impairs development
Too much sensory info can overwhelm children.
What is the general trend of brain plasticity in humans?
Plasticity increases from2-8 months, and declines until 10-20
It then rises a little, and slowly declines through to 70 years of age
What is the effect of prenatal exposure to alcohol and other drugs?
Baby is born very preterm or very small as shown by MRI
