Biology Flashcards
non-ending circular system
environment provides input to brain, brain processes input & triggers a behavioral output, behavior influences environment
Black Box system
genes & environment influence brain, which triggers a behavior
Reductionism
complexity of behavior reduced to most basic part; studying basic sections rather than a system in whole (allows analysis on different basis)
Rene Descartes
mind and body are different entities (interact over pineal gland) - also behavior triggered by reflexes - contradicts himself: mind controls body by sending animal spirits (info) down to muscle which in turn triggers movement (no mo. without mind)
Luigi Galvani
discovered electric nature neurons (electric stimuli causes contractions on nerve even when detached from body - mind sends electric signal through neurons which produces movement)
Luigi disproving theory Descartes
in order to move body needs electrical impulse from brain
Myelin sheath (Theodor Schwann)
wrapped around axon
Joseph Gall
brain contains different areas responsible for different functions -works like a muscle if used a lot it grows (bumbs on head demonstrate part of brain growing)
phrenology
reading of bumbs on head (Gall’s theory)
Brodmann
cerebral cortex divided in 52 sections - division based on neurons with similar characteristics
Cerebral localization
concept that specific part of brain are responsible fro different functions
Phineas Gage case
iron rod went through his skull, destroyed frontal lobe - affect his ability to inhibit activity
Silver staining (by Golgi)
strategy to identify separate neurons & learn more about their shape and structure - discovered neurons separate entities rather than branches in continuous network
Synapse
space between neurons, allows neurons to interact with one another
Neurotransmitter
chemical messenger transmitting signals between nerve cells in brain throughout nervous system (electro-chemical communication)
Penfield
send electric signal to different areas of cerebral cortex, while patient was awake; they had to describe what they were feeling
Patient HM (studied by Milner)
suffering with untreatable epilepsy: parts of both temporal lobe removed & hippocampus (elimination seizure & anterograde amnesia)
Simple cells (vision)
detect lines in environment
Complex cells (vision)
respond to movement
retina
when light enters eye through cornea, its projected onto retina; sensitive to light, containing photoreceptors, crucial for vision
Libet (pre-determinism)
conscious decisions predetermined by unconsciousness; the unconsciousness sends 300 ms before making the conscious decision to move your hand for ex. an electric signal
Neuron
basic, functional unit of nervous system; function is receiving and processing impulses from sensory receptors and other neurons and sends impulses to neurons or effector organs - like other human cells with soma, cytoplasm, organelles
Glia
support cells for neurons (helps to send electric signal); control blood flow in brain, control amount of neurotransmitter neuron releases, produces myelin sheath, produces and circulates cerebrospinal fluid (CSF)
cerebrospinal fluid
fluid surrounding spinal cord and brain, protects them in case of trauma & delivers nutrients to CNS
Soma
cell body of neuron; contains nucleus, mitochondria, …
nucleus
holds cells genetic info; containing chromosomes (type of protein - determines type of cell)
mitochondria
metabolic activity, energy function
Dendrites
branches emerging from soma - receives stimulation from several neurons over synapses; a lot of info at the same time
Axon
long cell body of neuron; electric impulse is send away from cell body along axon; send to axon terminal from which it is connected with effector organs or other neurons over synapse
effector organs
Muscles, organs, glands
Myelin sheath
axon covered in lipoprotein material; increases efficiency of neural impulse (otherwise slower, weaker, more energy needed)
afferent (neurons)
sends sensory input from PNS to CNS (info send away from senses towards a structure)
efferent (neurons)
info from CNS to PNS (effector organs) - produces movement
Neurons sending complex info?
receiving several inputs from different neurons (impulses with different durations, time between input,…) - integrator of info from multiple inputs; also decision maker (excitation or inhibition)
excitation
signal from one neuron to another (basically signal to other neuron to “fire and react”) - increases likelihood that receiving neon becomes active - dependent on neurotransmitter
inhibition
signal from one neuron to another _ decreases likelihood that receiver neuron becomes active (controlling/balancing excitatory signals - preventing overstimulation) - dependent on neurotransmitter
Central Nervous System (CNS)
brain & spinal cord
Peripheral Nervous System (PNS)
rest of body (excluding CNS)
Nervous System
network of nerves & cells that coordinates and controls activity around the body; enables communication between brain and body
Brain function
processes external sensory stimulation - producing voluntary and involuntary responses
Spinal cord function
contains bundles of sensory neurons, carrying somatosensory info from body to brain; also contains motor neurons who send info from brain to effective organs , produces reflexive behavior with little influence from brain
somatosensory info
sensory data collected from skin, muscles, joints,… (data that allows us to perceive physical sensations) - touch, temperature, Pain, pressure,…
Meninges
3 layers of protective membranes surrounding brain & spinal cord
Blood-brain barrier
protects CNS from toxins
Nerves (PNS) - axon
connect brain & spinal cord with rest of body - communication between muscles, skin , organs
Tract (CNS)
bundle of axons in brain and spinal cord
Ganglion (PNS)
collection of of neuron cell bodies
Tract (CNS) - axon
carry signals between different parts of brain, brain and spinal cord
Ganglion (PNS) - soma
signals are being processed before passing to other nerves
Nucleus (CNS) - soma
processing center for different infos & play key role in coordinating various functions in brain & spinal cord
Reference axes
system to identify & describe different parts of nervous system (3-Dimensional: Up-down, Left-right, Forwards-backwards)
Neuraxis
imaginary line in CNS (from lower end of spine to front of brain) to describe locations and directions of NS
Dorsal surface
top of head & back of body
Ventral surface
front of body
