ch 3 Flashcards
Neurons
communicate, send messages
motor neurons
allows feeling and us to react to our feelings
interneurons
allow all the neurons to communicate
support cells
glial cells: connect and clean up neurons
Over ____ billion
neurons in the body,
connected into circuits
100
Dendrites
Receive messages (input) from other neurons, tissue
Soma/cell body
houses the nucleus
Axon
Carries the message
Terminal buttons
-sends and releases the message
Dendrites and Soma
Integration & Summation
Take all of the inputs and combines them, deciding whether or not to continue “spreading the word”
Axon and Myelin Sheath
Transmits the message created in the soma to the terminal buttons;
Myelin Sheath: speeds transmission, insulates
Axon: electrical message (action potential)
Action potential
- negatively charged neuron, gets excited signals, changes from negatively charged to positively charged
- an electrical change that goes from negative to positive, resting to action potential
All or nothing Principle
-Either it fires, or it doesn’t fire
-Dependent On the activation level achieved by summing the impulses
-Intensity Differences?
Frequency of impulses
what does myelin do?
- Saltatory Conduction
- Allows the A.P to jump from node to node
- (graphic in PP)
Terminal Buttons
Release neurotransmitters to receiving neurons (dendrites)`
- sender neurons
- no physical touch tho
Synapse
space between neurons allowing for transmission bc they don’t physically touch, lock and key system
Neurotransmitters
neurons don’t send messages indiscriminately- they send specific signals to their neighbors
- due to genes and plasticity
- neighbors, then, are suppose to be adept at receiving these signals for further transmission
- hence, neurons tend to “buddy up” into circuits
Once released into synaptic cleft, neurotransmitters…
Bind to receptor sites
Excitatory or Inhibitory response
OR
remain in the cleft
Wherein they are (1) picked back up by the sender (reuptake), (2) remain in the cleft & available to the neighbor neuron, (3) are cleaned up by glial cells or lost, or (4) an enzyme changes the neurotransmitter so that it is no longer recognized by the receptor
Acetylcholine (Ach)
Muscle Movement, Memory, Arousal
Too much: convulsions, spasms, tremors
Too little: delusions, Alzheimer’s Disease
Endorphins
Pain, Mood
“Runner’s High”
Dopamine
Movement, Attention, Learning, Motivation
Too little: depression, ADHD, Parkinson’s disease
Too much: aggression, schizophrenia
Serotonin
Sleep, Eating,
Mood, Pain
sensory somatic nervous system
going to communicate things
automatic nervous system
only going to send out informations
Stress Response
- Brain Processes “Bear” (CNS) to which it metaphorically responds “Oh S*#$” – time for “flight”
- -Emotional responses process in the limbic-system of the brain (esp. the amygdala)
- -Note, signals originate from the eyes, which are in the PNS (sensory NS)
- Sends signals down the spine (CNS) so the body can respond (PNS)
Stress response cont.
-Sensory-Somatic NS
CNS says “run,” so we run
-Autonomic NS (Sympathetic)
–Adrenal gland atop the kidney releases adrenaline (epinephrine) & cortisol (a hormone)
–Increases breathing, heart rate, puts more O2 in the blood, & sharpens the senses
–Decreases the functioning of currently less important organs; e.g., bladder, digestive system, & sex organs
Immune-system?
Recovery
- Once all’s clear
- Brain tells the Sensory-Somatic NS that it can stop running (physically) & that the Autonomic NS can cool down
- –The Parasympathetic NS begins to counteract the recent turmoil, getting organs back to normal functioning (homeostasis)
-primates, particularly humans, are capable of creating stress outside of times on danger
-the baboon video-low ranking baboons had higher stress levels, then all the aggressive alpha males died off, but then the aggression kind of disappeared from the group. even when new baboons entered the group, they assimilated after about 6 months.
occipital Lobes
Visual Processing
Shape, color, motion
Temporal Lobes
Functions:
- Language comprehension
- Sound processing
- Memory Encoding
- –Enters new info into memory
- Visual Memories
Parietal Lobes
Functions:
- Spatial location
- Somatosensory processing (touch)
- -Registers sensations (scrapes, tickles, etc.)
- -More sensitive the body part = the larger area in brain
Frontal Lobes
-Separates humans from lower-order creatures Functions: -Planning -Memory search -Motor processing ---Precise movements -Reasoning -Emotion Regulation
Phineas Gage
-damage to the cerebral cortex
-Frontal Lobe Damage
-Rod through the head
-Changes in personality
Poor reasoning, self-control, social functioning
hemispheres
The Two Sides
Operates Contralaterally
Lateralization
hemispheres
The Two Sides Operates Contralaterally Lateralization -left brain "male" -right brain "female"
Lateralization: approach/ withdrawal
Left Side: Approach
Positive feelings
Pleasure/happiness
Anger
Right side: Withdrawal (Avoidance)
Negative feelings
Fear/Disgust
Central Core
Cerebellum, thalamus, hypothalamus, brainstem
Cerebellum
- Motor control (Punch Drunk” / “Real” Drunk)
- Temporal orientation & attention
Thalamus
relay station, encodes sensory information and sends responses, attention and sleep
Hypothalamus
he Four F’s (Fight, flight, feeding, and fucking), homeostasis
Brain Stem
Pons, Reticular Formation, Medulla
Pons
“Bridges” stem with upper brain
Sleep & facial muscles
Reticular Formation
Bodily arousal (activation), Alertness
Medulla
Breathing, swallowing, blood circulation
The Limbic System
- motivation and emotion
- connect PNS with CNS
3 parts of the limbic system -
hypothalamus
- amygdala (emotional arousal, fear, anger)
- Hippocampus (memory storage)
Patient HM
-At age 27 (1953), had surgery to correct for severe epileptic seizures
Removed much of the hippocampus
-H.M. could not store any new information
–Short-term to Long-term
Basal Ganglia
Important for “habit” formation
- Automatic behaviors
- -Example:Talking on the phone & driving
- Influences nucleus accumbens
- —Pleasure
- —-High dopamine concentration
How do we know this stuff
Brain Damage Studies:Dissection following death
Animal Research:E.g., rats
Brain Activity Measurements:
Relatively new
Einsteins Brain
didn’t want people to have it; wanted it to be destroyed bc eugenics was popular at that time
Reading the brain
Electroencephalogram
(EEG)
Electrical (brain) wave
data from firing neurons
Event-related potentials (ERP)
Magnetoenchephalogram (MEG)
Magnetic wave data
Computer-assisted Tomography (CT scan) [oldest]
X-ray images for structural information
Scanning the brain
Positron Emission Tomography (PET)
Radioactive substance to outline activity
Functional Magnetic Resonance Imaging (fMRI)
Magnetic field shows spatial resolution and function
Microstimulation
Experimental Technique
Note, previous were correlational
Electric Currents
Magnetic Pulses
