Paper 2: Topic 6: Biopsychology Flashcards
What are the 5 divisions of the nervous system
- The Central Nervous System
• Brain (centre of conscious awareness) & Spinal Cord (reflex actions)
• Coordinates incoming sensory information and sends instructions to other parts of the NS
• Cerebral cortex comprises grey and white matter - The Peripheral Nervous System
• Network of nerve fibres (axons) that connects parts of the body with the CNS
• Transmits messages from the CNS to muscles/glands 3. The Somatic System
• Conscious movement; myelination enables rapid transmission; reflex arc 4. The Autonomic Nervous System
• Involuntary bodily functions (eg breathing, heartbeat)
• Transmits information between organs; not as fast (unmyelinated) 5. Sympathetic & Parasympathetic Nervous System
• Fight or flight (sympathetic) and rest & digest (parasympathetic)
What’s the nervous system
The body’s main communication system which is very fast acting.
• It is a complex network of specialised nerve cells (neurons) which pass information around the body using electrical signals and chemicals (neurotransmitters).
What are the 2 divisions of the human nervous system
The central nervous system
The peripheral nervous system
What’s the 2 subdivisions of the peripheral nervous system
The autonomic nervous system
The somatic system
What’s the 2 subdivisions of the autonomic nervous system
Sympathies division
Parasympathetic division
What’s the central nervous system
Brain
Spinal cord
Function of the central nervous system
-Coordinates incoming sensory information and sends instructions to other parts of the NS.
-This is our store of knowledge and habits.
Structure of the central nervous system
Made up of the brain and spinal cord
• The brain is the centre of conscious awareness
• The cerebral cortex (3mm outer layer) is highly developed in humans and distinguishes our higher mental functions from other animals
• The spinal cord is an extension of the brain. It is responsible for reflex actions
Describe the cerebral cortex of the central nervous system
Cerebral cortex is also known as grey matter due to the colour of it.
It is made up of cell bodies.
The white matter is made up of axons which form fibre tracts
Structure of the peripheral nervous system
-made up of a Network of nerve fibres (axons) which are connected to the CNS
-it sends info to the CNS from the outside world and transmits messages from the CNS to muscles and glands (effectors) in the body
Describe the somatic nervous system of the peripheral nervous system
-controls conscious movement as it sends instructions from CNS to effectors in muscles and glands
-transmits info from receptor cells in sense organs to the CNS (takes info from external environ.)
-needs to act quickly as it’s made up of myelinated neurons
Describe the reflex arc of the somatic nervous system
1) stimulus detection: sensory receptor detects a stimulus
2) sensory neuron activation: The sensory receptor sends an electrical impulse along a sensory neuron towards the central nervous system (CNS), typically the spinal cord.
3) relay neuron: In the spinal cord, the impulse reaches an integration center. This is usually a synapse
between the sensory neuron and a motor neuron or an interneuron, which then relays the signal.
4) *motor neuron activation**: The impulse is transmitted to a motor neuron. The motor neuron carries the signal away from the CNS to an effector.
5) effector response: The effector, which is usually a muscle or gland, produces a response. For instance, in the hot object scenario, the effector would be the muscles in your arm, causing you to withdraw your hand quickly
Describe the pathway of the semantic nervous system
Stimulus -> sensory neuron -> relay neuron -> motor neuron -> effector (muscle/gland)
Function of the autonomic nervous system
-controls involuntary boldly functions which aren’t consciously directed eg: breathing, heartbeat, digestive processes and sexual arousal
-only transmits info to and from internal bodily organs (don’t need sensory pathways)
-acts more slowly than the SNS (somatic) and therefore made of unmyleinated nerve fibres
- divided into sympathetic and parasympathetic nervous system
Describe the sympathetic divisions of the autonomic nervous system
works with the endocrine system (comprising glands & hormones) to get the body prepared for fight or flight
