1: General Organisation of the Nervous System Flashcards
What is the definition of Neuroscience
Also known as Neural Science, is the study of how the nervous system develops, its structure and what it does
What is an example of a simple nervous system?
Hydra (Small freshwater Cnidarian)
- Nervous system consists of protonerve cells connected by a network of nerves
What does Cephalisation mean
Cephalization is the formation of a central nervous system
What is a protonerve
A nerve net consists of interconnected neurons lacking a brain or any form of cephalization
What consists in a complex nervous system?
- Brain and spinal cord is the centralised part
- Different parts of the body have peripheral specialisations (sense, organs, muscles)
- Nerves are the communication routes that link them together
What is in the Central Nervous system?
- Brain
- Spinal Cord
What consists in a Peripheral Nervous system?
- Sensory (Afferent Neurons)
2. Motor (Efferent Neurons)
What is the pathway for internal or external stimuli to reach the brain and for a reaction to occur
- Internal and external Stimuli
- Sensory receptors (except vision)
- Sensory (Afferent neurons)
- Reaches the brain
- Brain communicates with spinal cord
- Motor (efferent neurons)
- Two types of systems - Somatic System and Autonomic system.
What does the Somatic Nervous system consist of
Skeletal Muscle
What does the Autonomic Nervous system consist of?
- Sympatheic System
2. Parasympathetic system
What are the three regions of the brain called?
Forebrain
Midbrain
Hindbrain
Where is the forebrain?
The two cerebral hemisphere
Where is the midbrain and what functions does it have
Located towards the base of your brain.
- Visual
- Auditory inputs
Where is the hindbrain and what does it contain?
Hindbrain joins midbrain to the spinal cord
- It includes the pons and the medulla oblongata
All of this function collectively to support vital bodily processes.
What does the medulla control?
The medulla controls unconscious yet essential, body functions such as breathing, swelling, blood circulation and muscle tone.
What is the function of the cerebellum?
Co-ordinating centre and also functions in learning complex motor tasks.
What does the forebrain control?
Thoughts, senses, words and deeds
What does gyri mean?
Ridges
What does suli mean?
Grooves
What is the structure of the Midbrain?
- Simple structure
- Roof is tectum
- Differentiates into superior colliculi (Visual tracking) and
- Inferior Colliculi (Auditory processing)
- Aqueduct connects ventricles III and IV
- Floor is tegmentum
How is the Midbrain involved with movements.
- There are two pairs of dopamine nuclei in the midbrain
- Substantia nigra is part of the motor control system
- Its output is to the striatum (basal ganglia)
- Degrdation of this area causes Parkinson’s disease
- Tremor and difficulty imitating movements.
How is the midbrain involved with pleasure and perception?
- Ventral tegmental area projects to limbic system and frontal cortex
- The mesolimbic path terminates in the nucleus accumbent and signals rewards
- Addictive drugs act here
- Malfunction in the meso-cortical path is common in Schizophernia
What does the Hindbrain - Medulla do?
- The most caudal section - least modified from spine.
- Control autonomic homeostatic systems: damage is fatal
- Breathing rhythm
- Temperature control
- Blood glucose levels
- Includes Reticular Formation.
What’s the purpose Hindbrain - Cerebellum and Pons?
- The rostral hindbrain
- Dorsal cerebellum
- Ventral pons “bridges” left and right
- Carries axons into cerebellum
- Contains important nuclei controlling sleep, waking and arousal.
How is the Cerebellum involved with coordination and learning
- Cerebellum or “little brain”
- Integrates information about the body’s position with motor commands.
- Learn movement sequences and runs them sub-consciously.
- Damage causes loss of co-ordination.
What is the function of the Autonomic Nervous System?
- Autonomic nervous system controls “visceral” functions. (Related to internal organs)
- It has sympathetic (excitatory) and parasympathetic (inhibitory) divisions.
What is the function of the Somatic and Visceral
- Somatic relates to somites and equates to voluntary
2. Visceral relates to internal organs (viscera) and equates to involuntary (autonomic)
What is the Cerebrospinal Fluid (CSF)
- Brain and spinal cord are hollow
- Covered by arachnoid membranes (meninges)
- Cavities filled with cerebro-spinal fluid.
