Neuroscience Flashcards
What can the nervous system be split into (2 major systems)?
Central Nervous System
Peripheral Nervous System
What is part of the CNS
The brain and spinal cord
What is part of the PNS
Everything else which isn’t the CNS
What can the peripheral nervous system be split into
Sensory division
Motor division
What can the motor division be split into
Somatic nervous system
Autonomic nervous system
What does the enteric nervous system do
It is part of the autonomic system which is in charge of controlling the muscular contractions of the GI tract
Located in walls of the GI tract, and controls digestive activity (peristalsis and secretion of enzymes)
What can the autonomic nervous system be split into
Sympathetic
Parasympathetic
What is the function of the central nervous system
Various things like processing information and generating thoughts
What is the function of the peripheral nervous system
Sensory input and informational relay, as well as control of bodily movements
What is the function of the sensory division
This division is responsible for relaying sensory information of the body to the brain
Responsible for picking up sensory information
Also meant to detect internal stimuli
What is the function of the motor division
To be able to control aspects of the body’s movement / function
Carries out responses initiated by the CNS - transmits signals to allow for movement
What is the somatic nervous system
This aspect of the nervous system controls the voluntary movements of skeletal muscles
What is the autonomic nervous system
This aspect of the nervous system regulates the involuntary functions of various body parts
What is the sympathetic branch
This is responsible for the body’s ‘fight or flight’ responses - in other words it can stimulate heart rate, dilate pupils and inhibit digestions
What is the parasympathetic branch
This is responsible for the body’s ‘rest and digest’ responses - in other words it can help the body conserve energy and perform maintenance functions –> i.e. decreased heart rate, constricted airways, constricts pupils etc
WHat are the different forms of protection to the CNS
Bone
Meninges
Blood brain barrier
Explain the function of the bone in protecting the CNS
The bone acts as a structural barrier/protection from hard impacts or sharp objects
It is hard, dense bone which resists impact and external forces, which prevents direct trauma to the brain
Not only seen in brain, but also in the spinal cord, where it acts as a shock absorber in the spinal vertebrate to protect the spinal cord
Explain the components of the meninges and a brief outline of what it does
It is a flexible sheet between brain/spinal cord and bone, made from 3 membranes. Its aim is to protect the brain from damage from the skull (i.e. asudden impact causing the brain to jolt and hit the skull –> need some protection there)
There are 3 parts:
Dura mater
Arachnoid mater
Pia mater
Explain the function of the dura mater (what does it do)
This is the outermost and toughest of the 3 menginges, lying just beneath skull and vertebral bones
It is a thick, durable membrane made of dense fibrous tissue. It helps provide the initial guard against trauma
Explain the function of the arachnoid mater (what does it do)
It is the middle layer of the meninges, just under the dura mater. It is a web-like, thin membrane loosely covering brain and spinal cord
it also consists of the subarachnoid mater which is right below that layer of arachnoid, and is filled with cerebrospinal fluid (CSF), which helps cushion the brain and spinal cord
Explain the function of the pia mater (what does it do)
Is the innermost layer, adhering directly to the surface of the brain and spinal cord. It is a delicate membrane
Its function is to support blood vessels that supply the brain and spinal cord and works with other meninges to help protect CNS
Explain the function of the blood-brain barrier
This is a functional barrier rather than a structural barrier. It aims to shield the brain from harmful substances, whilst allowing essential nutrients to pass through
It works as the brain requires a lot of blood –> a lot of blood vessels surrounding it. These blood vessels have special, smaller walls, which restrict the entry of many chemicals into the CNS –> protects brain from chemicals, which is especially important as the brain is sensitive to toxins
The endothelial cells lining blood vessels in brain are packed tightly by tight junctions –. prevents movement of substances between them, thereby acting as a barrier preventing substances entering
What happens at the spinal cord level (in terms of reflex arcs)
Spinal cord is a cable of neural fibres with “roots” brnaching off
Provides an interfae between brain and the PNS
It enables reflexes to occur –> spinal reflex, and thus the reflex arc:
Stimulus –> receptor –> sensory neuron –> integration centre –> motor neuron –> quick response
Ultimately the spinal cord allows for reflexes, and also the executioon of bodily responses, and coordination of complex movements
What are the fluid filled cavities in our brain called
Ventricles
What is the function of the ventricles
Produce cerebrospinal fluid (CSF) which is essential for cushioning the impact that a brain/head might experience
They ultimately cushion and protect the brain, provide buoyancy, maintain chemical stability and distribute nutrients
What does the brainstem do
It is able to link the brain to the spinal cord. It controls the life supporting functions of the body
It is the ‘stalk’ the brain is connected to
Passes down the neck to spinal cord, and is thus responsible for the autonomic nervous system
What can happen to it after a head injury, and why would that be dangerous
After a head injury, it could pose a risk to the brainstem. This could lead to being disabled or even death in extreme cases
Where is the cerebellum located
It is at the back of the brain and is inferior to the occipital and temporal lobes
What does the cerebellum do
It is responsible for controlling movement (voluntary), balance, and motor learning. thus, it receives a lot of the sensory input (auditory and visual input)
It contains 70% of the brains neurons, even though it only takes up 10% of the brains space.
What structures sit at the centre of the brain and on top of the brainstem
Thalamus and hypothalamus
What is the function of the thalamus
It is responsible for some sensory processing / sensory relay to cortex and also control of sleep
What is the function of the hypothalamus
Hypothalamus is responsible for maintaining homeostasis, and thus initiates the release of hormones in the body
What parts of the brain make up the limbic system
Cingulate cortex
Hippocampus
Olfactory Bulb
Amygdala
What is the function of the limbic system
Emotional processing, memory and motivation
What is the function of the cingulate cortex
This is related to emotions and also pain regulation/response (?!)
WHat is the function of the olfactory bulb
It receives the signals associated with smell and provides a short way for it to link to the amygdala (smell bypasses the thalamus and goes straight to amygdala)
What is the function of the amygdala
Function is for fear response and emotion
What is the function of the hippocampus
Assists with being able to translate information in the short-term memory to long-term memory
What is the function of the basal ganglia
Action and thought
It helps with motor control, cognitive/emotional processes, and helps regulate motor movement and helps inhibit unnecessary or unwanted movements. Also helps with motor learning
Formation of habits as well
What are the components of the basal ganglia
Caudate, putamen and ganglia
What is the function of the caudate
Learning and memory
What is the function of the putamen
Works with caudate to regulate movement and influence learning
What is the function of the globus pallidus
Regulation of voluntary movement and motor learning
What is the neocortex
The convoluted folds on the top of the brain
Why is the neocortex wrinkled
To increase the surface area of the brain, and allow for different functions Otherwise, it is too big to fit on the top of our head
What are the lobes of the neocortex
Temporal
Frontal
Parietal
Occipital
What is the function of the frontal lobe
This is responsible for higher order processes, such as decision making, information processing
Also responsible for planning and executive functions
Motor control, language production and emotional regulation happening here as well
What is the function of the parietal lobe
Cruciail for processing sensory info, spatial awareness, and integration of sensory info
What is the function of the temporal lobe
In charge of auditory processing, memory and language
Also language comprehension here
What is the function of the occipital lobe
Responsible for visual processing
it interprets and integrates visual information, allowing for recognition of objects, perception of colours and depth
What connects your two hemispheres of the brain
Corpus Callosum - alows for communication between two sides of the brain
What happens as the nervous system becomes more complex
As nervous system becomes more complex, the complexity of the organism increases - they have more complex behaviours
What is the difference between vertebrates (w/ a bone) and non-vertebrates in terms of the nervous system
Vertebrates have a separation between PNS and CNS. Meanwhile. non-vertebrates don’t have this separation between PNS and CNS