Chapters 1 and 2 Flashcards
how do neurons communicate through signals
electrical signals travel down a neuron as an action potential. At the synapse the message changes to a chemical signal and is carried by the neurotransmitters that were emitted when the axon opened. The adjacent neruons dendrite can choose to quiet or pass the singal on one which either
What happens when messages repeatedly go through neurons
The synapse gets stronger with repeated activity, higher percentage of important messages being passed through.
How does the brain process information?
Networks of neurons make up circuits they control information processes
Example of a simple circuit
relfex circuit
what are complex circuits
integrates information from many brain circuits to generate a response
How do we build circuits
Your genes, before birth, create simple circuits and new experiences build stronger circuits!
Action Potential
How our brain cells communicate
how many neurons are there
billions
What is the largest part of the brain and how is it divided
cerebrum, left and right hemisphere
how is the cerebrum connected?
by nerve fivers carrying information,
What is the bridge connecting the cerebrum called?
the largest of the nerves forms a bridge called the corpus callosum
What are the layers and folds on the surface of the brain called
cerebral cortex
where is the frontal lobe located and what does it control (7)
The front top of the brain. It controls movement, speech memory, emotions, planing, problem solving and personality.
Where is the parietal lobe located and what does it control
the top behind the frontal lobe. It controls senses, visuals, and taste
Where is the occipital lobe located and what does it control
the bottom back of the brain. visuals and recognizing colors and shapes.
Where is the temporal lobe located and what does it control. What are two important structures and what do they do
the bottom eye level of the brain. Auditory information. Hippocampus: encodes new memories and long term memories. The amygdala also controls memory and associating memory with emotions
What structures are apart of the limbic system and control (5) and what brain section?
Controls emotion and motivation. Thalamus(sensory) hippothalmus (hormonal signals to the body through pituitary gland) as well as the amygdala and hippocampus (forebrain)
What is the midbrain
eye movement + trigger reflexes to control motion of pen and musical instrument. (collection of neurons)
What is the basal ganglia
controls complex movements and smooth
what is the hind brain
glucose regulation and sleep (also includes the cerrebellum)
cerrebellum definition
half of the neurons are located here. also split into two sides. learn new mnotor skills.
what would happen if the cerrebellum was damaged
you wouldn’t put your finger to your nose
Pons
below the cerrabellum and focuses on breathing and posture
what structures are apart of the brain stem
pons, and medulla, midbrain
Olfactory bulbs
sense of smell in the forebrain
how did the brain evolve
new neurons and repeated behaviors strenthening the neurons
What are neural networks
regions spanning neurons form nerve tracts and multiple nerve tracks form a neural network
what are neural tracts and an example
many neurons compiled together like the corpus callosum between the two hemispheres
How does seeing a shape on a tv influence brain actibity of signals
the signal travels to the optic tract then to the thalamuys where it is processed and then to the cortex and back. That creates a feedback loop. Then the signal is transfered to the temporal lobe to identity the shape and parietal lobe to locate where the shape is.
What are brain waves
electrical patterns from feedback loops
what are the 4 types of waves
Alpha, Beta, Theta, Delta
Concious waves and when+where they are produced
Alpha: Parietal and Occipital when brain is relaxed
Beta: Frontal and Parietal when sensory and tasks appear
Unconcious waves and when they are produced
Theta: sleep
Delta: deep sleep very slow signals
What are the conditions for signals up or down and what strucutre do they go to
Up: senssing to the thalamus and cortex
Down: Movement to the medulla and spinal cord
What are neural circuits
sections of neurons in the brain that process different information. They are organized in collums. And each one influences each other
Two types of neurons and what they do
Excitatory: 80% push neurons toward firing signals
Inhibitory: 20% spuress and regulate signals
What would happen if there was an imbalance of two neuron types
A disorder that would cause seizures like epilepsy
What is a glia
a supporting cell for neurons
Explain what these 4 glia types do
Astrocytes
microglia
ependymal
oligodendrocytes
ion concentration, nutrients, form neuron connections
immune - protects neurons from damage or infection
cerebrospinal fluid
neuron functions improve
Explain the formation of a neuron
The dendrite collects signals and the axon transmits signals
What is the resting neuron potential
-70 millivolts
What do other neurons do to another neurons singlas
they can depolarize or hyperpolarize the likely hood to generate an action potential
What happens when a neurons signal reaches a certain voltage
the ion channels open which lead to movement down the axon to transmit the signal to another neuron
What happens the axon opens
Calciums ions go in releasing neurotransmitters that help the chemical signal get across the synaptic cleft into the other neurons dendrite.
How are neurotransmittors synthesized
they are built in the ribosome space of the cell. A vesicle with neurotransmittors bud off of the golgi apparatus and leave the cell.
What are the two receptors on the dentrites called
ionotropic and metabotropic
explain ionotropic receptors
neurotransmittor binds to ion channel and moves in
metabotropic receptors
neurotransmitter binds to protein which releases biochemical steps to move in
What does astrocyte glial cells do in signal passing
they clear excess neurotrasmittors to keep from clogging or too many signals
what are the two most common neurotransmittors, what do they do and what neuron cell are they located in
Glutamate(excitatory, depolarize membrane = signal fired)
GABA(hyperpolarize, preventing fire, inhibitory)
What are the two types of receptors that help neurotransmittors (not the pass, but to function)
AMP - faster
NMDA - slower
are neuron receptors specefic to molecules are where are they located
They are located sometimes both on the surface or inside, depending on the diffusion ability of specific molecules that the neuron is made for
Explain gene expression in neurons
all neurons have the same DNA but the expression is different from chemical changes to chromain
chromatin
protein and DNA that determines gene expression
Tay-Sachs Disease
a mutation that codes for a problem in fat metabolism
Genome sequencing
determing the DNA sequence of a person
Transduction
food/light/senses converted to electrical signals
What are the three neurons in the retina
Photoreceptors, interneurons, and ganglion cells
what are the two types of photoreceptors and what do they do
rods (see dim light) cones (see detail and color)
Explain how light is processed in the brain starting from the eye
Light reaches the ganglian cells to the photoreceptors (converting to electrical signals) which sends the signals to the optic chiasma where the left and right visuals of both retinas converge and travel to their left and right side of the brains where the go through the thalamus to the visual cortex
Explain the two layers of the retina
fovea, innermost layer and contains the most photoreceptors that contain cones of red and green
Macula, the outer layer, enables you to read and drive. Damage to this is the main cause of blindness
Explain the visual cortex
A thin, half-dollar, neural tissue at the occipital love. It has many dense layers of cells. The middle layer receives the eyesight thalamus signals.
What can happen when the brain favors one side of the eye?
The unused eye goes blind
Explain the process of hearing, Waves being turned into electrical signals
Waves hit the pinnae of your ear where the eardrum vibrates sending the waves to 3 bones that push the wave through the oval window into the fluid cochlea which converts the waves to electrical signals by hair cells
how is the cochlea shaped and made with it’s special abilities
a winding membrane with thousands of hair cells tuned to certain frequencies.
How does the cochlea turn waves into chemical signals
ions rush in after the wave is received which excites the auditory nerve sending it to the brainstem then thalamus then cerebral cortex
Which side of the brain understands and produces speech
The left side3
What would happen with damage to the auditory cortex
You would hear speaking but not understand it
what are the two senses that are linked
taste and smell
How do we process taste and smell
through molecules in air and food
what are the strucutres of taste that experience neurogenesis
olfactory neurons and taste buds (which regenerate)
Explain taste buds
50-100 sense gustatory cells that catch at least one taste: smell, sour, salty, bitter, and savory
Explain how the brain processes taste and lavel the 3 crainel nerves
The taste buds sense the taste and send signals through 3 craniel nerves: facial, glossopharyngeal, and vagus nerves to taste regions in brainstem t the thalamus to the gustatory cortex in the frontal lobe
Explain how smell is processed and what is unique about how smell is processed
odors enter the axons which travel to the 2 olfactory bubls which travel to the olfactory cortex in the temporal lobe. Smell is the only sense that is not sent to the thalamus before the cortex
What are olfactory cells
1,000 cells and 20 x amount of different smells.
what makes taste and smell a pair
smell enhances taste
What is touch scientific word
somatosensory system
Which two organs stimulate the cortex the most
lips and fingertips
what determines more sensitive organs to senses
more cells and how dense those sells are
Describe and explain the two factors associated with pain
Emotion and sense. Emotion is distressing and pain is stimulated.
What causes tissue damage
nociceptors
what do nociceptors also respond to besides pain
spice and itch
What happens after tissue damage occurs
chemicals, inflammation, nerve impulses, continued pain
Why do people have different pain tolerance and how is it relieved?
brain processes pain in different ways and the natural release of endorphins relieves pain
