Charles Darwin
english naturalist that came up with evidence that evolutionary change is caused by natural selection (Origin of Species 1859)
Phylogeny
tree of life -> the history of organismal lineages as they change through time; we are all related to each other and every living thing
trait
any detectable variation (purple) in genetic characteristic (color)
genes
the unit of heredity found on chromosomes which make up anatomy and behavior
genotype
actual encoding of genes on chromosomes
phenotype
physical appearance
chromosome
a compact form of DNA; average human is 23 pairs of chromosomes
nucleotides
building blocks of DNA - guanine, thymine, adenine, cytosine
sex chromosomes
23rd pair; 2 X's (female), XY (male); some disorders carried on these
dominant
refers to an allele (variation of gene) that is fully expressed in a heterozygote's phenotype
recessive
not observable in a heterozygote's phenotype
down syndrome
have 3 copies of chromosome 21 - 1 in 700
Huntington's Chorea
fatal degenerative disease of the nervous system; you don't experience systems around 40; located on chromosome 4
neuron
a type of cell that receives and sends messages from the body to brain and back to the body; sent by weak electrical current
sensory neuron
neurons that carry incoming information from sense receptors to the central nervous system; external stimuli to internal impulses
motor neurons
carry out going information from the central nervous system to muscle and glands
inter neuron
communicates and intervenes between sensory inputs and motor outputs; connects to other neurons
dendrite
receives messages from other neurons
soma
cell body; body of the neuron that receives and sends messages down the axon
axon
carries information away from the cell body
axon terminals
branches that link the dendrites and somas of other neurons
neurotransmitters
chemicals used to relay, amplify, and modulate electrical signals between one neuron and another cells; stores in synaptic vesicles
acetylcholine
chemical transmitter in the peripheral and central nervous system; activates muscles and memory; associated with Alzheimer's disease; alertness, memory, sexual performance, learning
norepinephrine
helps control alertness and arousal; under supply can result in a depressed mood
dopamine
influences movement, learning, attention, emotion; excessive receptor activity leads to schizophrenia or lack tremors and decreased mobility to Parkinson's disease
tardive dyskenia
involuntary, repetitive movements manifesting a side effect of long term of high dose use of dopamine antagonists, usually antipsychotics
catecholamines
epinephrine/norepinephrine leads to high levels on stress; from psychological reactions or environmental stressors can cause high levels that cause CNS trauma
serotonin
affects mood, sleep, hunger, arousal; low levels associated with depression, anxiety, bipolar disorder
glutamate
excitatory neurotransmitters which is involved in memory; oversupply can overstimulate brain which leads to migraines or seizures
endorphins
help with pain; biomedical compounds produced by the pituitary gland and the hypothalamus invertebrates; long term endorphin implies a pharmacological activity
oxytocin
associated with the ability to maintain healthy interpersonal relationships
GABA
chief inhibitory neurotransmitters; induce relaxation and sleep; too little leads to seizures and insomnia
melatonin
regulates skin cycle; anti-aging hormones
synapse
specialized junction through which cells of the nervous system signal to one another and to non neuron cells (muscle, glands)
terminal buttons
small knobs at the end of an axon, release chemicals called neurotransmitters
synaptic transmissions
the process by which information is communicated
plasticity
property of a neuron or synapse; change its internal parameters in response to its history
glial cells
non neuron cells that provide: support, nutrition, homeostasis, myelin, signal transmission in nervous system
myelin sheath
consists of fat-containing cells; insulate the axon from electrical activity; increases the rate of transmission of signals
multiple sclerosis (MS)
occurs when myelin sheath is destroyed; numbness, weakness, paralysis
resting potential
electrical charge of an inactive neuron
threshold
trigger point for a neuron's firing
action potential
nerve impulse
ion channels
axon membrane has these tiny holes or tunnels
negative after-potentials
when a neuron is less willing to fire
receptor site
areas on the surface of the neurons and other cells that are sensitive to neurotransmitters
polarized
when an action potential runs along an axon
refractory period
a pause in between firings where the neurons has to recharge
all or nothing law
a neuron either fires or it doesn't
axon hillock
anatomical part of a neuron that connects the cell body (soma) to the axon
L-Dopa
used to treat catatonic schizophrenia; lowers dopamine; same drug can have different effects on people
central nervous system
brain and spinal cord
peripheral nervous system
all parts of the nervous system outside brain and spinal cord
somatic nervous system
messages to and from skeletal muscles and sense organs; controls voluntary behavior
autonomic nervous system
serves internal organs and glands; controls autonomic functions such as heart rate and blood pressure
sympathetic nervous system
arouses body; emergency system; animals react to threats; general adaptation system -> stress builds up
parasympathetic nervous system
quiets body; most active after an emotional event
spinal nerves
31; carry sensory and motor messages to and from the spinal cord
cranial nerves
12 pairs that leave the brain directly; communicate messages
spinal cord
transmits messages to and from the brain
reflex arc
automatic behavioral pattern: occurs when a stimulus (auto response)
sensory neurons
nerve cell that carries messages from senses to CNS
motor neurons
cell that carries commands from the CNS to muscles and glands
fight or flight
the decision to stay and fight or to run away from a dangerous situation
brain stem
brain's basement where the spinal cord enters the skull and swells slightly forming the medulla
(controls system for heartbeat and breathing; inside lies your reticular formation)
hindbrain
consists mainly of medulla and cerebellum; located at rear base of skull below cerebral hemispheres
medulla oblongata
controls vital life functions such as heart rate, swallowing, and breathing
pons
balance and hearing (bride)
cerebellum
behind spinal cord controls posture and balance
reticular formation
inside medulla/brainstem; controls alertness, attention, arousal, and some reflexes (Reticular Activation System
midbrain
above the pons; sensory information and relays it upwards
superior colliculu
important for visual system flexes
inferior colliculus
important for auditory system function
thalamus
receives info from all senses except smell
hypothalamus
regulates emotional behaviors and motives (sex, hunger, rage, hormone release)
Limbic System
system within forebrain closely related to emotional response and motivating behavior
septum
Olds and Milner called this the "pleasure center" of the brain
amygdala
associated with fear and anger responses
hippocampus
associated with storing permanent memories; helps us navigate through space
anterograde amnesia
inability to make new memories
retrograde amnesia
memories prior to event are forgotten
Brenda Milner and HM
showed that by cutting out a certain part of HM's brain, seizures stopped but he suffers from amnesia, but still has procedural memories; different types of memories stored in different parts of brain
cerebral cortex
outerlayer of the cerebrum; contains 70% of the neurons in CNS
cerebrum
two large hemispheres that cover upper part of the brain
corticalization
increases in size and wrinkling of the cortex
neocortex
top layer of cerebral hemispheres; 2-4 mm thick; 6 layers
cerebral hemispheres
right and left halves of the cerebrum
corpus callosum
bundle of fibers connecting cerebral hemispheres
frontal lobe
decision making, problem solving skills, purposeful control of behavior, consciousness, and emotions
parietal lobe
receives sensory information from body, responsible for perception and coordination
occipital lobe
responsible for vision (located back of head)
temporal lobe
memory, emotions, hearing, language, learning
contralateral
the other side - a stroke affecting right side may cause paralysis on opp side
ipsilateral
the same side of the brain
aphasia
language disturbance resulting from brain
wernicke's area
inability to understand speech
broca's area
inability to make speech
Roger Sperry
studied split brains --> cutting corpus callosum; test with objects
Michael Gazzaniga
inspired by Sperry; lateralization of hemispheres; different things for different hemispheres
endocrine system
glands that pour chemicals directly into bloodstream or lymph system
pituitary gland
regulates growth via growth hormone
hormones
chemicals produced by endocrine system
anterior pituitary
produce hormones that regulate: ovaries and testes; breast milk production; metabolism; reactions to stress
posterior pituitary
produce hormones that regulate: conservation of water in the body, breast milk secretion, uterus contractions
hypo/hyper pituitary dwarfs
perfectly proportional but tiny
too much growth
thyroid
produce hormones that regulate: metabolism, physical growth and development
hyper: thin, tense, excitable; hypo: inactive, sleepy, slow obese
parathyroid
produce hormones that regulate: calcium levels in body
pancreas
produce hormones that regulate: glucose metabolism
adrenal glands
produce hormones that regulate: fight or flight response; metabolism (salt balance); sexual desires (especially in women), stress; epinephrine (fear); norepinephrine (anger)
ovaries
produce hormones that regulate: production of eggs, ova, developments of female sexual characteristics
testes
produce hormones that regulate: development of male sexual characteristics; sperm production; sexual desire in men
pineal gland
regulates body rhythms and help with sleep cycle; release hormone melatonin which responds to daily variations in light
Flourens
experimental method of carrying out localized lesions of the brain in living rabbits/pigeons --> motor movements and behavior
Franz Gall
proposed that different parts of the brain had different functions; phrenology: skull feeling for personality
ablation
surgical removal of parts of the brain
lesions
a thin wire electrode is lowered into a specific area inside the brain: electrical current is used to destroy a small amount of the brain
CT scans
computer enchanced x ray of the brain or body
MRIs
uses a strong magnetic field not an X ray; to produce an image of body's interior
Functional MRI
makes brain activity visible
PET Scans
computer generated color image of the brain activity; based on glucose consumption in the brain
Electroencephalograph EEG
detects, amplifies, and records electrical activity in the brain
Electrical Stimulation of the Brain
electrode used to activate targets areas in the brain
Neurogenesis
production of new brain cells
Right Brain
good at perceptual skills, and at expressing and detecting other's emotions; simultaneously, holistically
Left brain
better at math, judging time and rhythm, and coordinating order of complex movements; 95% sequentially, analysis
Taste
5 different tastes: sweet, bitter, sour, salt, umami
Male and Female Brain Differences
1. men have 4% more brains cells (100 g) more than women
2. women have more dendritic connections between brain cells
3. women have a larger corpus callosum - better transfer between both hempispheres
4. women use both sides of the brain for language whil