central nervous system and human behaviours Flashcards
what is the spinal cord responsible for ?
reflex actions (e.g. pulling your hand away from a hot plate
what does the spinal cord do ?
passes messages to and from the brain, linking it to the peripheral nervous system
what is the spinal cord ?
a tube-like structure
what is the brain ?
- source of our conscious awareness
- where decision making takes place
how is the brain divided ?
into two near-symmetrical hemispheres
what are the two hemispheres connected by ?
corpus callosum
how does the brain control the body ?
contralaterally- left hemisphere controls the right side of the body and vice versa
what distinguishes our mental activity from other animals ?
our cerebral cortex is highly developed
what is the thalamus ?
the brain’s relay station
what is the main job of the thalamus ?
receives information from various senses and passes it on to the appropriate areas of the cerebral cortex for high level processing
what are some other things that the thalamus does ?
- carries out some initial processing of its own
- acts as a ‘gate’ or filter for information
- thought to play a role in sleep, wakefulness and obsessive compulsive disorder
where is the hypothalamus ?
sits below the thalamus
what three things does the hypothalamus control motivation for ?
1) hunger
2) thirst
3) sex
what subcortical structure is in control of the ‘fight or flight’ system ?
the hypothalamus - key role in the stress response
what role does the hypothalamus play in maintaining homeostasis ?
- maintains balance in bodily functions such as body temperature
- regulates the endocrine system through its connection to the pituitary gland
what is an example of a structure that is part of the limbic system ?
the amygdala
what role does the amygdala play ?
large role in regulating emotional responses (such as aggression)
what are two things that the limbic system plays a role in ?
memory and learning
what does the limbic system do structurally ?
limbic system is interconnected with areas of the cortex, integrating cortical and subcortical parts of the brain
what does cerebellum mean ?
‘little brain’
what are two characteristics of the cerebellum ?
- has two hemispheres
- very convoluted (wrinkled)
what is the primary role of the cerebellum ? how does it do this ?
1) coordinates posture, balance and movement
2) does this by receiving and integrating information from the spinal cord and other areas such as the motor cortex
what is the corpus callosum ?
a dense collection of nerve cells
what does the corpus callosum do ?
- physically connects the two hemispheres bellow the cerebral cortex
- allows communication between the two hemispheres by passing signals back and forth
why is the corpus callosum so critical to the body ?
the brain controls the body contralaterally and the corpus callosum allows this to happen by allowing the two hemispheres to pass signals between them
what three things does the corpus callosum play a vital role in ?
1) self-control
2) impulsive regulation
3) inhibition of aggressive behaviour
what did Coccaro et al. 2007 discover about the corpus callosum in terms of aggression ?
they found that patients with psychiatric disorders that feature aggression, activity in the orbifrontal cortex in reduced, which disrupts the corpus callosum by imparing the impulse control function (the patients are more impulsive with their aggressive responses)
the two hemispheres have different functions, what is this known as ?
lateralisation
within each hemisphere, certain areas are responsible for specific functions and behaviours, what is this called ?
localisation - for example, not only are language functions lateralised to the left side of the brain. they are also localised to certain areas within it
what is the most striking characteristic of the cerebral cortex ? and what is it its purpose ?
it is very convoluted - to increase the cortex’s surface area, giving it more processing power
how is the cerebral cortex structured ?
it is separated into four lobes of each hemisphere named after the bones under which they lie (so eight in total and four in each hemisphere)
what do the frontal lobes control ?
- high level cognitive functions such as:
1) thinking
2) planning
3) problem-solving
4) decision-making
what do the frontal lobes contain ?
the motor cortex
what is the motor cortex ?
a long strip of neurons that runs down along the central sulcus of both hemispheres
what does the motor cortex control ?
each motor cortex controls voluntary actions for the opposite side of the body
what is the left frontal lobe known as ?
Broca’s area
where are the parietal lobes ?
on the other side of the central sulcus, further back in the brain
what lies directly alongside the central sulcus in the parietal lobes ?
the somatosensory cortex
what does the somatosensory cortex do ? and in what manner ?
processes sensory information from the skin (e.g. touch, temperature and pressure), does this contralaterally
where are the temporal lobes ?
beneath the lateral sulcus of each hemisphere
what does each temporal lobe contain ?
an auditory cortex which deals with sound information coming mainly from the opposite ear
what do the temporal lobes do ? and what does this mean ?
they process the location, volume and pitch of sounds - have a role in understanding language
where are the occipital lobes ?
located at the back of the brain
what does each occipital lobe contain ?
a primary visual cortex
how does our vision work ?
everything we see in our right field of vision is initially processed by the left visual cortex before sharing (via corpus callosum) with the right visual cortex
