Neuron
Synaptic transmission.
release PreSyn, diffuse at the synapse, enter postsyn... bind to the NeuRec
Electrical nerve impulses travel down the axon
Transmission of nerve impulses across the synapse is chemical
Structure
Learn to SPELL myelin sheath my-elder-violin
she-th
Nucleus
Node of Ranvier
Part of axon that’s not covered by myelin sheath, where nervous impulses Jump over.
Types of neurons in CNS
Motor neurons carry commands from the motor cortex of the brain (CNS) out to the muscles of the
skeleton.
Relay neuron (also known as interneurons) is to interconnect sensory and motor pathways, arid
also different parts of the CNS.
Sensory neurons carry inforrnalion from sense organs into the central nervous system (CNS).
Excitation & Inhibition
Excitation (binding of NeuTrans onto Recepters) making nerve impulse more
likely to trigger/fire
Inhibition (binding of NeuTrans onto Recepters) making nerve impulse less
likely to trigger/fire
Excitation increases/facilitates neural activation in the postsynaptic neuron
Inhibition decreases/dampens neural activation in the postsynaptic neuron
Inhibition is vital in order to maintain a balance between excitation and inhibition,
needed for normal brain functioning Such as falling asleep GABA
Excitation is vital in order to maintain a balance between excitation and inhibition,
needed for normal brain functioning Such as intense motor movements Dopamine, AcH
Explain neurons in action
• Sensory neurons: receptors in BODY PARTS would sense the SENSATION from the STIMILI and
send that information via the PNS to the sensory neuron in CNS.
• sensation are received by SN through relay neuron. Analysis of the sensation and decision are
made in the brain.
• The decision instructs the motor neurons through relay neurons to PNS, so that BODY PART did
the ACTION.
Types of Nervous System
Fight or Flight
Fight or flight: Bodily reactions to threat or danger by activating the HPA cortex
pathway and the SAM system designed to provide energy and arousal for rapid
responses.
high blood levels of glucose and fats, along with raised heart rate and blood pressure.
RETURN TO NORMAL after out of emergency
Appraisal (sensory processing systems) --> Activation of the 2 systems by the
hypothalamus (at the base of the brain), HPA->then adrenal gland secretes
hormones SAM->adrenal medulla secretes adrenaline
Split Brain
Brain Function
Lateralization
Neuroplasticity