7-14 Flashcards
What is the function of neurotransmitters?
Transmit signals across synapses between neurons.
Where are neurotransmitters stored?
In synaptic vesicles at the axon terminal.
How do action potentials trigger neurotransmitter release?
Calcium ions enter, activating proteins that fuse vesicles with the membrane.
What is the role of glial cells in neurotransmission?
Remove neurotransmitters from the synaptic cleft and recycle them.
What do ionotropic receptors do?
Open ion channels when neurotransmitters bind, changing the membrane potential.
What is the difference between EPSP and IPSP?
EPSP excites; IPSP inhibits neuronal firing.
What is the main excitatory neurotransmitter?
Glutamate.
What are GABA and glycine’s role?
They are inhibitory neurotransmitters.
What is neuromodulation?
Modifies neuron activity without directly causing action potentials.
Where are noradrenaline neurons located?
In the locus coeruleus.
What effect does dopamine have?
Involved in reward and pleasure.
How does neurotransmitter recycling occur?
Vesicles are refilled with neurotransmitters after their release.
What are drugs that alter consciousness and interact with neurotransmitter systems in the brain?
Drugs like stimulants and sedatives.
How do drugs contribute to addiction and dependence?
Drugs hijack brain systems, promote dopamine release, and lead to physical and psychological dependence.
How does alcohol affect neurotransmitter systems in the brain?
Alcohol dampens excitatory messages and promotes inhibition, leading to relaxation and sleepiness.
What is nicotine’s effect on the brain?
Nicotine activates acetylcholine receptors, promoting alertness and concentration, but it’s highly addictive.
How do amphetamines affect neurotransmitter release?
They release dopamine and serotonin, causing arousal, pleasure, and a sense of well-being.
What receptors are involved in touch sensation?
Meissner’s, Merkel’s, Ruffini, and Pacinian corpuscles detect touch, pressure, and vibration stimuli.
What is a receptive field?
The receptive field is the skin area a receptor responds to; varies in size.
How do touch receptors adapt?
Meissner’s and Pacinian corpuscles adapt quickly; Merkel’s responds to sustained pressure.
What is the sensory pathway for touch?
Sensory nerves enter the spinal cord, relay in medulla/thalamus, project to somatosensory cortex.
How do nerves cross the body?
Nerves cross the midline: right body side is represented in the left hemisphere and vice versa.
How is the body mapped in the somatosensory cortex?
The body is mapped with distorted representation due to uneven receptor density (fingers more sensitive).
What is cortical plasticity?
Experience can reshape the sensory homunculus,
