CNS, PNS and Neurons Flashcards
How many neutrons does it take to transmit pain from our foot to our brain?
3
How many neutrons are needed to transmit a motor signal fro our brain to our foot?
2
What does Neuroanatomy mean?
The structure and connectivity of the nervous system.
What does neurophysiology mean?
How neurins work an communicate.
What are the two subdivisions of the Peripheral nervous System?
Somatic and Autonomic.
What does the somatic nervous system do?
Controls voluntary movement.
What does the autonomic nervous system do?
Controls involuntary (automatic) responses.
What are the nerves in the Somatic Nervous System responsible for? (2)
- Transmitting signals from the CNS to the body for voluntary movement (efferent).
- Delivering sensory information from the body to the CNS (afferent).
What are the nerves in the Autonomic Nervous System responsible for?
- Regulating the automatic behaviours of the body – heart rate, blood pressure, respiration, digestion etc.
What are the two subsystems of the Autonomic Nervous System?
Sympathetic and Parasympathetic.
What does the Sympathetic Nervous System do?
stimulates (fight or flight response)
How does the Sympathetic Nervous System stimulate?
Accelerates heart rate, dilates pupils, decreases digestive functions.
What does the Parasympathetic Nervous System do?
Inhibits (rest and digest).
How does the Parasympathetic Nervous System inhibit?
Constricts pupils, decelerates heart rate, increases digestive function.
What are the main functions of the brain? (4).
Receives and processes information.
Initiates responses.
Stores memories.
Generates thoughts and emotions.
What are the 3 main sections of the brain?
Hindbrain.
Midbrain.
Forebrain.
What does the Hindbrain consist of?
Cerebellum, Pons and Medulla.
Where are the Pons and Medulla located?
In the Brain Stem.
What is the Medulla responsible for regulating? (6)
Heart rate,
Circulation,
Respiration,
Sleep / Wakefulness,
Levels of arousal / consciousness,
Reflexes (e.g. swallowing, coughing & sneezing, vomiting).
How does the Medulla achieve this regulation?
The medulla contains the origin points for a lot of nerve fibres, specifically cranial nerve fibres. These nerve fibres carry information from the brain stem to the structures in the head, face, neck and some organs.
What does Pons mean in Latin?
Bridge.
What is the Pons responsible for?
Regulating arousal, sleep and dreaming. Pons is also an origin point for a lot of nerve fibres.
Where is the Cerebellum?
The Cerebellum sits at the base of the brain behind the brainstem.
What does cerebellum mean in Latin?
Little brain.
What is important about the structure of the Cerebellum?
The cerebellum has a similar structure to the brain however, the folds are much tighter which allows the cerebellum to contain over 50% of the neuron’s in the brain despite only accounting for less than 10% of its weight.
What is the Cerebellum responsible for?
Fine motor coordination, motor learning, balance, gait & posture and proprioception.
What is Proprioception?
Our sensation of our body and limbs in space.
Where is the Midbrain?
The midbrain also makes up part of the brainstem.
What does the Midbrain consist of? (2)
Tectum and Tegmentum.
What are the two sections within the Tectum?
Superior Colliculus and Inferior Colliculus.
What does the Superior Colliculus do?
Orients us towards visual stimuli.
What does the Inferior Colliculus do?
Orients us towards auditory stimuli.
What is in the Tegmentum?
The Tegmentum contains neurotransmitter nuclei involved in movement and arousal.
Why is the Substantia Nigra black?
The Substantia Nigra contains a very high concentration of Dopaminergic Neurons, one of the by-products of dopamine is near-melanin which causes the surrounding tissue to become stained in the this black colour.
What are Dopaminergic Neurons?
Neurons that produce Dopamine.
Why is Dopamine so important?
Dopamine is an essential neurotransmitter for motor initiation.
What causes Parkinson’s Disease?
The death of Dopaminergic Neurons in the Substantia Nigra. Therefore, the dark pigmentation is lost as the cells of the Substantia Nigra start to die, the death of these neutrons causes other parts of the brain to become dysfunctional causing the common traits of Parkinson’s.
Why doe we require the forebrain?
We could live with just the Hindbrain and Midbrain but we require the Forebrain to make us human.
What does the Forebrain consist of? (4)
Limbic System.
Basal Ganglia.
Hypothalamus.
Thalamus.
What is the Cerebral Cortex?
The overarching name for the components of the Forebrain, cortex just means outer layer therefore, the cerebral cortex is just the outer layer of the cerebrum.