Retake Study Flashcards
Focused flashcards based on the midterm (35 cards)
Synaptic Transmission
This is the process whereby action potential is translated from an electrical to a chemical signal in the form of neurotransmitters and passed from one neuron, at the synaptic terminal, to another, the postsynaptic cell. The signal is formed into neurotransmitters by vesicles and carried into the synaptic cleft where it is detected and binds to ion-gated channels. This allows the Ca2+ receptors ion-gated channels to open up and allow Ca2+ ions to enter into the channel and presynaptic cell’s terminal button. There are calcium-sensitive proteins in the presynaptic cell that are activated by calcium, and they prompt the synaptic vesicles to fuse to the cell membrane, releasing their NTs into the synapse. NTs bind to the postsynaptic receptors. The postsynaptic receptor then opens up allowing the passage of Ca2+ and neurotransmitters a specific neurotransmitter to enter. This then sets off the signal Incoming ions trigger the action potential for the postsynaptic cell and the channels close. Leftover neurotransmitters are reuptaken into the presynaptic cell or broken down by enzymes and flushed from the system.
Action Potential
This is the process where a signal is sent from one neuron to another down the cell’s axon. Resting state is at -70mV, inside of the cell is negative and the outside is positive, the Na+ channel opens and depolarization occurs as Na+ rushes into the cell and the cell becomes more positive on the inside than on the outside of the cell. When the inside of the cell reaches +40mV, the Na+ channel closes and K+ rushes into the cell. This causes the repolarization to occur as the inside of the cell becomes more negative and the outside more positive. The cell overcorrects before reaching the resting phase.
Motor Loop
Afferent from motor and sensory areas of the brain to the putamen then the the thalamus. The thalamus then projects back to the motor cortex giving the coordinated movement
Cognitive/Associative Loop
Afferents from various cortical areas reach the caudate nucleus and nucleus succumbant which contains dopaminergic connections (providing reward affirming feelings), then projections reach the thalamus and then back to the cortical areas
Limbic Circuit
hippocamus, amygdala, and the limbic lobe all project to the caudate nucleus, which fires dopaminergic projections, sending signals to the thalamus (of what behaviors to promote or inhibit), the thalamus projects back to the limbic areas of the cortex
Acetylcholine (cholinergic)
Links motor neurons to muscles, plays an important role in attention, memory and sleep; found in many parts of the brain; excitatory at neuromuscular junction, inhibitory in the heart
Dopamine
A type of monoamine: catecholamine; related to motivation and reward, modulates movement, activation of circuits in prefrontal cortex, attention, learning; dopaminergic; Many mental disorders and parkinsons
Norepinephrine
A type of monoamine: catecholamine; related to cognitive functioning to increase arousal, vigilance, and influences the reward system; influences sleep and the sympathetic nervous system (rel: meth)
Epinephrine
A type of monoamine: catecholamine; generally a hormone, prepares the body for action and diminishes other bodily processes that aren’t needed in stressful situation; “adrenaline”
Serotonin
A type of monoamine; plays a role in transmission of neurochemicals, sleep, eating, arousal, pain, switches affecting various mood-states- regulation of mood
Glutamate
An amino acid; major excitatory neurotransmitter in CNS, primarily in hippocampus and amygdala, important in learning
GABA
An amino acid; inhibitory in CNS, most important in mediating synaptic inhibition; decreases activity, lowers arousal
Sleep Deprivation
Hippocampus loss, gray matter loss, and decreased activity in the frontal and temporal lobe; attention, vigilance, higher order decision making and mood difficulties
Caffeine
Binds up adenosine triphosphate (ATP), caffeine interferes with sleep for up to 10 hours,
Cerebellum
“The little brain”, located in the back of the brain and responsible for sensory, motor, balance/coordination, memory, learning, emotion
Lobes: Frontal Lobe
problem solving, organization, inhibition, planning
Lobes: Temporal
Contains the limbic cortex, amygdala, and hippocampal formation; processing auditory information, affect, memory, and recognition (Left: verbal, right: nonverbal)
Lobes: Occipital
Near the back of the brain, responsible for vision (most specialized part of the brain)
Lobes: Parietal
Processes somatosensory information (speech, pain, spatial orientation)
Meninges
Contains: dura, arachnoid membrane, and pia mater; located between the skull and the brain; primary function is to help protect the brain
Blood brain barrier: cells involved
tight juncture of endothelial cells (and astrocyte feet)
Blood brain barrier: purpose
blocks toxins and bacteria while allowing the passage of water, some gases, and lipid-soluble molecules by passive diffusion; as well as the selective transport of molecules such as glucose and amino acids that are crucial to neural functions
Circle of willis
A loop of connected blood vessels at the base of the brain that is responsible for supplying blood to the brain. Looping pattern serves a protective role and if there is damage to part of it, the blood can still get to all parts of the brain (it would just be slower)
Glymphatic systems
the brain’s unique waste disposal system; cerebral spinal fluid is pumped through the tissue and flushed into the circulatory system (then goes to the blood circulation system and to the liver).