Biopsychology (Paper 2) Flashcards
Nervous system
Our nervous system is divided into two parts. The central nervous system and the peripheral nervous system. They carry messages to and from the brain.
Central Nervous System
This is made up of the brain and the spinal cord and its main function is the control of behaviour. The CNS is the centre of all conscious awareness. It receives messages from the sensory receptors and sends messages to muscle glands in the body. It also picks up information and reacts to regulate your body.
Peripheral Nervous System
This consists of all the other nerves that are not in the CNS. They relay information from nerve impulses (electrical signals) from the rest of the body back to the CNS. It is further divided into two parts the somatic nervous system and the autonomic nervous system
Somatic Nervous System
The somatic nervous system is the part of the PNS that could be said to ‘talk to’ the outside world. It includes both sensory receptors and motor pathways.
Autonomic Nervous System
The autonomic nervous system regulates involuntary actions (e.g. Heart beat etc.). It is split into two sections: Sympathetic nervous system and Parasympathetic nervous system.
Sympathetic nervous system
Gets us ready for emergencies and is involved in the flight or fight response.
Parasympathetic nervous system
Restores natural order, relaxing us after a emergency.
Fight or flight response
Helps us deal with short-term problems that can be solved by fighting or running. Unfortunately, many of the threats we face in our society do not fall into these categories
Sympathomedullary pathway (SAM)
The amygdala sends a distress signal to the hypothalamus. The hypothalamus picks up this stressor then sends a impulse to the sympathetic ganglia. The ganglia are connected to the main organs which affects there functioning when the impulse is picked up. They are also connected to the adrenal medulla. When the signal reaches adrenal medulla adrenaline is released which can lead to changes in the body causing someone to flight or fight.
Pituitary Adrenal System (PAS)
Amygdala sends a distress signal to hypothalamus. The hypothalamus releases CRH which stimulates pituitary gland. The pituitary gland then releases ACTH which then triggers the adrenal cortex. This then releases corticosteroids e.g. cortisol which counteracts the adrenaline returning the body to a normal state. This happens alongside the SAM process but at a slower rate so actually kicks in 30 seconds after adrenaline is released.
Cell body
Contains the nucleus .
Dendrites
Extend from the cell body and carry electrical impulses from other neutrons towards the cell body
Axon
Extension of the neutron. Carries electrical impulses assay from the cell body to other neurons.
Sensory neuron
Sensory neurons carry nerve impulses from sensory receptors (e.g. vision, taste, touch) to the CNS (spinal cord and the brain).
They have long dendrites and short axons.
Relay neuron
Most neurons are neither sensory nor motor but sit somewhere in between – allowing the two other types to communicate. They are called relay neurons. Carries info across the spinal cord/brain from sensory nerves to motor neurons. They have short dendrites and short axons.
