Brain & Behaviour Flashcards
What is the brain responsible for?
Driving behaviour
Controling behaviour
Ending behaviour
What does understanding the brain allow us to understand?
Behavioural differences in life stages
Behavioural differences in breeds
Effects of early experiences on behaviour
Why behaviour may turn into dysfunctional behaviour
What are the 3 main regions of the brain?
Hindbrain
Midbrain
Forebrain
During embryonic development what develops into the 3 regions of the brain?
Neural tube
What develops from the forebrain during embryonic development?
The 2 cerebral hemispheres
What is the surface of the cerebral hemispheres known as?
Cortex
In different animals how is the cortex different?
In different animals the cortex are wrinkled differently
What is the cortex subdivided into?
Sensory cortex
Motor cortex
What are the ridges of the cortex’s wrinkles known as?
Gyri
What are the crevices of the cortex’s wrinkles known as?
Sulci
True or false
The number of gyri and sulci are specific/different for each species
True
Each species has a set number of gyri
Each species has a set number of sulci
How are the gyri and sulci formed in each species?
How each gyri and sulci is formed is also specific/different for each species
Why is the brain wrinkled?
The reason the brain has a wrinkled surface is to increase surface area
The more neurones in a given region the more important the role of that region is to the animal
Do all animals have a wrinkled brain?
Not all animals have a wrinkled cortex
How wrinkled a cortex is depends on the species
Why does cortex wrinkles vary between species?
The brain is an energetically expensive organ
The brain uses a lot of energy
The brain is about 2% of an individual’s body weight but how much of the bodies oxygen does the brain use?
20% of the bodies oxygen
20% of the bodies blood flow will be in the brain
Due to the high energy costs of the brain what will happen to a part of the brain which isn’t needed anymore?
Due to the high energy costs if an animal does not need a specific brain area for a specific brain function it will disappear as the species evolves
This is to reduce unnecessary energy costs
What are the 2 main types of behaviour produced by the brain?
Involuntary behaviour
Voluntary behaviour
What parts of the brain control involuntary behaviour?
Hindbrain
Midbrain
What parts of the brain control voluntary behaviour?
Forebrain & hindbrain
Voluntary behaviour is mainly controlled by the forebrain
Give examples of types of involuntary behaviour
Non-motivated behaviour
Involuntary reflex behaviour
True or false
The hindbrain and midbrain that controls involuntary behaviour are evolutionaryly ancient
True
What 3 reasons do we know that the hindbrain and midbrain are evolutionaryly ancient
They’re found in some of the oldest fish
They’re very similar across all species in functions
They are barely affected by developmental processes
Involuntary behaviour has some learning via what?
Motor learning
What are the things that become involuntary behaviour known as?
Motor sequences
What are motor sequences?
Motor sequences are sequences of events that happen very rapidly one after the other
Motor learning produces a fluid production of rapid sequences
Involuntary behaviour can be modified by inputs from the forebrain leading to involuntary behaviour modifications via what 3 ways?
Habituation
Sensitisation
Associative learning
True or false
Each brain region is connected to the others and can alter their functions if necessary
True
True or false
The hindbrain is mostly the same in all vertebrate animals
True
What are the 3 main subregions of the hindbrain?
Medulla
Pons
Cerebellum
Give examples of unlearnt Reflex actions that the medulla coordinates?
Swallowing
Sneezing
Vomiting
What does the hindbrain s medulla control with its ‘vital centres’?
Heartbeat
Breathing
Blood pressure
What can happen if the hindbrain medulla is damaged?
If the hindbrain’s medulla is damaged it can result in unconsciousness
What does the pons mediate?
Startled reflex
Grasping
What varies in the involuntary actions controlled by the hindbrain’s medulla and pons?
The involuntary actions controlled by the hindbrain’s medulla and pons vary on whether or not we can override or ignore them
They also vary on what degree you can override the involuntary behaviour
Define startle
Startle = Feeling or showing sudden shock or alarm
What part of the brain controls the startle response?
The hindbrain’s pons
The startle response is an indicator used for what?
Startle responses are a type of indicator we can use to measure an animals anxiety levels to assess its welfare
The startle response is automatic but what modulates it?
The startle response is automatic but modulated by input from the forebrain’s amygdala activating
What does it mean that startle responses are invariant and rigid in the way animals express them?
Startle responses are usually the same/similar startle responses seen in all vertebrates
Give an example of an involuntary action?
In human neonates you can see involuntary walking/stepping reflexes even though they haven’t learnt to walk yet
Those reflexes will disappear when their forebrain is developed enough to inhibit the reflexes
Neonates = an infant less than 4 weeks old
What are the 2 main functions of the hindbrain’s cerebellum?
Control postural reflexes
Sequence learning & production
What are postural reflexes?
Postural reflexes are reflexes that aid in balance via posture while doing something
How does the hindbrain’s cerebellum control postural reflexes?
The hindbrain’s cerebellum controls postural reflexes by receiving inputs from appropriate sensors around the body that tell the cerebellum the bodies posture and it’s relation to gravity
The cerebellum gets all this information and synthesises it so it knows what signals to send down the spinal cord to cause the bodies muscles to adjust the bodies posture
Give examples of inputs from appropriate sensors around the body that help control postural reflexes?
The visual system tells the cerebellum which way is up and which way is down
The inner ears vestibular system also contributes to the sense of balance and spatial orientation for the purpose of coordinating movement with balance
What can we still see if the forebrain and/or midbrain are damaged?
Due to the hindbrain’s control of involuntary behaviour patterns, if the forebrain and/or midbrain are damaged then we can still see simple behaviour patterns in those individuals
The behaviours seen in these forebrain and/or midbrain damaged individual are usually what?
Species specific behaviours
Unlearnt responses
Give some examples of situations where we can still see the simple behaviour patterns in individuals with damaged forebrain’s and/or midbrain’s
Decerebrated dogs will still do scratching, stepping patterns and limb withdrawal reflexes
Anencephalic babies can still swallow and show grasp reflexes
True or false
The midbrain varies in size and position in vertebrates
True
Give examples that show that the midbrain varies in size and position in vertebrates
In birds the midbrain is fairly enlarged and is known as the optic tectum in birds
In mammals the midbrain is really small and buried within the other areas of the brain
How many colliculi are in the midbrain and what are their roles?
The midbrain has 2 colliculi
1 responds to visual stimuli
1 responds to auditory stimuli
What are the jobs of the midbrain’s colliculi?
Colliculi are regions that respond quickly and automatically to stimuli
1 colliculi responds to visual input while the other colliculi receives an auditory input leading to rapid adjustments and responses to the sources of the stimulation
What is the midbrain’s ventral tegmental involved in?
The midbrain’s ventral tegmental area is involved with reward processing
The midbrain’s ventral tegmental area helps process motivationally important information and rank which behaviours need performing first
The presence of the midbrain’s colliculi is the cause of ‘blindsight’ what does this mean and how does it work?
Blindsight is where you’ll react to visual and auditory stimuli even though the forebrain’s visual cortex is damaged
This is because the eyes and ears are directly connected to the midbrain generating a behavioural response to the stimulation
Give 3 examples of rapid behaviours generated by the midbrain
Turning your head to a sound you just heard
Frogs shooting their tongues out at prey
Prey avoiding a predator attack after hearing something or seeing the predator in the corner of their eye
What kind of behaviour does the hindbrain’s cerebellum help control?
Involuntary behaviour
Voluntary behaviour
In terms of voluntary behaviour what does the hindbrain’s cerebellum aid in?
Motor coordination
How does the hindbrain’s cerebellum aid in motor coordination?
To aid in motor coordination the hindbrain’s cerebellum received inputs from the motor cortex and sends signals back to the forebrain to generate a response
How does the hindbrain’s cerebellum aid in motor coordination?
To aid in motor coordination the hindbrain’s cerebellum received inputs from the motor cortex and sends signals back to the forebrain to generate a response
What is the hindbrain’s cerebellum used to control?
The hindbrain’s cerebellum is used to control fine muscle control and postural changes to ensure fluid body movements/actions
The hindbrain’s cerebellum programs final muscle control so that:
- antagonists to an action prevent over-shoot
- postural changes can be accommodated and are not disruptive
- muscles involved in all the relevant joints are coordinated
- an action can occur well without feedback
This allows you to voluntarily do an action very fast without the forebrain controlling it
Give an example of how the hindbrain’s cerebellum is used to control fine muscle control and postural changes to ensure fluid body movements/actions
An example of this is seen with people who can play an instrument
When first learning the instrument you need engagement of the forebrain
When the motor patterns needed to play the instrument are learned then the behavioural control to play the instrument moves from the forebrain to the hindbrain’s cerebellum
What part of the brain is responsible for motor learning?
The hindbrain’s cerebellum and the forebrain’s dorsal striatum are responsible for motor learning
True or false
The cerebellum is an area of the hindbrain that can change due to learning/experiences
True
The cerebellum is the only hindbrain region to be altered by learning
Does the hindbrain’s cerebellum vary between species?
The hindbrain’s cerebellum is also the only hindbrain region that varies greatly across species
Give examples of how the hindbrain’s cerebellum varies across species
In birds their cerebellum’s are very large relative to the rest of their entire brain
Animals that fly have extremely large cerebellum’s relative to the rest of their brains due to how important coordination is when flying
In mammals the cerebellum varies in size dependent on species
How does alcohol affect the cerebellum?
When you’re drunk the alcohols ethanol affects the cerebellum leading to the incoordination
How does alcohol affect the cerebellum?
When you’re drunk the alcohols ethanol affects the cerebellum leading to the incoordination
What can be seen with cerebellum impairment?
Tremors
Incoordination
Individuals with malfunctioning cerebellum’s are uncoordinated especially when they’re trying to pay attention to something
What can cause cerebellum impairment?
Congenital problems
Give an example of a congenital problem that affects the cerebellum
Parvovirus can affect cerebellum development leading to adult animals being uncoordinated
Cerebral impairment can be due to cerebral hypoplasia
Cerebral hypoplasia is a neurological condition in which the cerebellum is smaller than usual or not completely developed
What are the 3 key subregions of the forebrain in regards to behaviour control?
Pre-frontal cortex
Basal ganglia
Motor cortex
Because the forebrain has 2 hemispheres what does that mean for the forebrain regions that control voluntary behaviour?
The forebrain has 2 hemispheres meaning that there’s going to be 2 of every region
True or false
Each hemisphere of the forebrain controls the opposite side of the body
True
What affects the forebrain’s control on behaviour?
All of the forebrain’s control on behaviour is affected by early experiences
For animals environmental enrichment or level of complexity of an environment in early stages of life can affect how their forebrain’s control behaviour later on
What is the pre-frontal cortex responsible for?
The pre-frontal cortex is responsible for supervision and planning of behaviour
The pre-frontal cortex moderates impulsivity and distractibility
If you hear someone say something stupid the pre-frontal cortex stops you from reflexively slapping them so you can actually think if it’s worth using your energy to do so
There’s individual variation between individuals on what the pre-frontal cortex will inhibit, but why is this?
The pre-frontal cortex function varies in individuals due to differing early life experiences
What can impaired function of the pre-frontal cortex lead to?
Some forms of:
- Obsessive Compulsive Disorder (OCD)
- Attention Deficit Disorder (ADD)
- Drug addiction
What causes some forms of OCD and drug addiction?
OCD and drug addiction happen due to the pre-frontal cortex’s impairment causing an abnormal locking onto a goal
They become obsessed with achieving something at an abnormal level due to increased impulsivity
What causes ADD?
ADD happens due to the pre-frontal cortex’s impairment causing an abnormal failure to achieve a goal
They become unable to focus enough to achieve a goal due to increased distractibility
Pre-frontal cortex function impairment can be seen in humans and non-human animals due to different types of disorders
In people without any disorders pre-frontal cortex function varies and worsens due to what?
Immaturity
- being too young that your pre-frontal cortex hasn’t developed)learned enough to function properly
Ageing
Stress
What are basal ganglia and what are their roles?
The basal ganglia are structures within the forebrain that are loops that run from the pre-frontal cortex
The basal ganglia are used to translate thoughts into action
How does the basal ganglia work?
Within the forebrain there are loops that run from the pre-frontal cortex down to the basal ganglia and then back up to the motor cortex
You’ll think about whether or not to do an action in your pre-frontal cortex
If you decide to do the action the message will be through the loops down to the basal ganglia
The basal ganglia will then coordinate action selection and then send a message up through the loops to the motor cortex to do the decided action
The motor cortex will then cause the body to do the action
What are basal ganglia used for?
Turning stimulus into response
Turning intention into action
Action selection
Connecting the pre-frontal cortex (the decision making region) with the motor cortex
What is the basal ganglia important for?
The basal ganglia are important for balancing inhibition and activation control for all voluntary behaviours
True or false
There are several loops that run through the basal ganglia that are in charge of different things
True
True or false
The basal ganglia helps decide what would be the best way to do the action decided on by the pre-frontal cortex
True
What is the name of the basal ganglia important for motivation, appetitive behaviour and in regulating effort/obstacles overcome?
Ventral striatum or nucleus accumbens
Ventral striatum = nucleus accumbens
Appetitive = characterised by a natural desire to satisfy bodily needs
What does the ventral striatum/nucleus accumbens control?
Appetitive behaviour
Appetitive = characterised by a natural desire to satisfy bodily needs
Regulating effort/obstacles overcome
Deciding if a reward is worth the effort to get it
What is the name of the basal ganglia that is important for consummatory behaviour?
consummatory behaviour = a behavior pattern that occurs in response to a stimulus and that achieves the satisfaction of a specific drive
Dorsal striatum
What can the dorsal striatum be divided into?
Caudate
Putamen
Name the basal ganglia responsible for motor control
Motor loop
What can impaired motor loops cause in humans?
If the motor loop is impaired in humans it can lead to diseases affecting motor control
Give examples of disorders where the motor loop impairment causes too much movement
Tourette’s
Huntington’s
What are disorders where the motor loops impairment causes too much movement known as?
Hyperkinesis disorders
Give an example of a disorder where the motor loop impairment causes too little movement
Parkinson’s
What are disorders where the motor loop impairment causes too little movement known as?
Hypokineses disorders
Explain the basal ganglia impairment in Parkinson’s
The slowness is caused by loss of neuronal activity in the input pathway to the caudate and putamen
The slow movements are due to the loss of the motor loop, meaning neuronal message doesn’t reach the dorsal striatum
What would happen if basal ganglia has tissue missing?
If basal ganglia has tissue missing then you can get either:
- exaggerated and uncontrolled behaviour
- loss of behaviour
How does a voluntary behaviour occur from the forebrain?
First the pre-frontal cortex behaviour decides what the individual wants to do
Then the pre-frontal cortex sends a message down a loop to the basal ganglia
The basal ganglia then decides how it would be best to do the action the pre-frontal cortex has decided on
Once the best action has been decided upon the basal ganglia then send a message to the motor cortex
The motor cortex will then make the body perform the action
What 3 areas of the brain can send information directly to the motor cortex?
Basal ganglia
Pre-frontal cortex
Cerebellum
How are the neurones arranged in the motor cortex?
Neurones for processing motor outputs in the motor cortex are arranged topographically
Neurones within the motor cortex are arranged based on which parts of the body they control
Neurones within the motor cortex are also organised proportionately relative to the regional importance
Neurones in the motor cortex are organised proportionately based on how important the body part is to control
True or false
The motor cortex does control all body parts equally
False
The motor cortex does not control all body parts equally
The motor cortex devotes more neurones to regions that need to be controlled with particular dexterity
Any emotional output is often what?
Any emotional output is often asymmetrical
What is an emotional motor output in humans?
An emotional motor output is any sort of facial control to show your emotions
Which side of the brain is better at processing emotional stimuli, and how does this show in the body?
The right side of the brain is better at processing emotional stimuli
Due to this emotional expression is commonly more expressed on the left side of the body
In humans why is it thought that the right side of the brain is better at processing emotional stimuli?
In humans this is thought to be because the left side of the brain is dominated by language centres
Due to this the left side of the face and body is emotionally more expressive in humans and is also known to be seen in some primates
What has research into non-primate species’ emotional motor output shown?
Research into non-primate species has shown emotional motor output to be asymmetrical in some species
