Unit 1: Biological Bases of Behavior (Green Mod) Flashcards
Heredity
passing of traits from parents to their offspring through genes
Natural selection
A process in which individuals that have certain inherited traits tend to survive & reproduce at higher rates than other individuals because of those traits.
What do twin and adoption studies show about development?
Both studies highlight the significant role of genetics in personality, but also the crucial impact of parenting + environment on development.
Molecular genetics
A field of study that seeks to identify specific genes influencing behavior.
Heritability
The extent to which variation among individuals can be attributed to their differing genes.
Epigenetics
Environmental factors like stress or trauma can activate or suppress certain genes by turning them on or off, without changing the DNA sequence.
localization of function
the concept that diff. parts of our brain is responsible for diff. things
what are the 5 steps of the progression of neural firing? (DSATs)
1st: the message starts at the dendrite
2nd: soma
3rd: axon
4th: terminal button
5th: synapses
action potential
enables the neurotransmitter to travel through the neuron
refractory period
the neurons enter a rest state after firing (after depolarization)
All-or-Nothing Principle
signal is either fully sent or not sent at all; there’s no weak signal
Myelin Sheath
- a fatty substance encasing most not all, the ones that do are better protected, neurons in the brain
- mylien protects & insulates the axon, speeding up transmission of nerve impulses.
list 2 disorders that can happen due to disruption to the impulse delivery process.
1) Multiple Sclerosis (MS)
2) Myasthenia Gravis
Multiple sclerosis (MS)
- a condition that can affect the brain & spinal cord.
Being an autoimmune disorder, it mistakenly attacks healthy parts of the body. The immune system attacks the layer that surrounds & protects the nerves called the myelin sheath.
This damages & scars the sheath and possibly the nerves, slowing or disrupting nerve signals.
Myasthenia Gravis
a rare long-term condition that causes muscle weakness.
Can affect most parts of the body.
Caused by a problem w/ the signals between the muscles + nerves, thus damaging the communication system between + making muscles easily weak and tired.
Neurons (or nerve cells)
our main communicators within our bodies
Reuptake
the sending neuron recollects neurotransmitters
function of actylcholine (ACh)
enables muscle action, learning & memory
function of dopamine
A neurotransmitter associated with movement, emotion, attention and learning & the brain’s pleasure and reward system.
function of serotonin
enables hunger, arousal, mood & sleep
function of norepinephrine
A neurotransmitter involved in alertness & arousal
function of GABA (gamma-aminobutyric acid)
a major inhibitory neurotransmitter; regulates sleep and wake cycles
function of glumate
major excitatory neurotransmitter; involved in memory
function of endorphins & the pathways its linked to
- function: pain relief + pleasure
- linked to pain + pleasure pathways
function of p substance & its associated disorder
function: pain perception
associated disorder: involved in the transmission of pain signals
How do drugs & other chemicals alter neurotransmission?
They affect brain chemistry at synapses, often by either exciting or inhibiting neurons’ firing.
agonists
a molecule that, by binding to a receptor site, results in a similar effect as the natural neurotransmitter
Antagonists (drugs)
bind to neurotransmitter but don’t activate them. Instead, they block the receptor & prevent the natural neurotransmitter from exerting its effects
This inhibition can dampen or completely block the action.
Epinephrine (Adrenaline)
- Both a neurotransmitter & hormone
- Boosts energy and increases alertness
- Primary chemical in “flight or fight” responses
Indirect agonists (also known as re-uptake inhibitors)
can block reuptake of a neurotransmitter
What do most psychoactive drugs have in common?
- they alter mental states
- activate dopamine-producing neurons in the
brain’s reward systemthis increase in dopamine is associated w/
greater reward, which can lead to a stronger
desire to take the drug again.
What is the effect of a drug primarily dependent on?
which neurotransmitter(s) is affected.
Sensor & motor neurons are not the S.A.M.E.
Sensory: Afferent signals arrive at the brain
Motor: Efferent signals exit the brain.
- the only way our thoughts can exist in the
world.
CNS (Central Nervous System)
- brain + spinal cord
- the body’s decision maker
PNS (Peripheral Nervous System) & list what systems it includes.
- gathers info. + transmits CNS decisions to:
somatic nervous system & autonomic nervous system
somatic nervous system
voluntary control of our skeletal muscles
autonomic nervous system & list the 2 types of systems it includes
everything that happens automatically in our bodies
1. sympathetic nervous system:
- arousing
- fight or flight
- parasympathetic nervous system:
- calming
sympathetic nervous system
the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations and triggering the “fight or flight” response.
parasympathetic nervous system
the division of the autonomic nervous system that calms the body, conserving its energy
sensory neurons (input)
- carry messages from the body’s tissues +
sensory receptors inward to the brain + spinal
cord
interneurons
our brain’s internal communication center
motor neurons (output)
carry instructions from the central neurons system out of the body’s muscles + glands
reflex
when a sudden decision needs to be made, the backup neurons will make them
what do the motor, sensory + interneurons do when faced with an immediate pain stimulus?
the motor, sensory & interneurons in your spinal cord will make the executive decision before the brain can
lesioning
scientists selectively destroy tiny clusters of brain clusters, leaving the surrounding tissue unharmed
EEG (Electroencephalogram)
an amplified readout of brain wave activity; provides a basic, not very detailed readout
CT scan
examines the brain by taking X-ray photographs that can reveal brain damage
PET scan
shows brain activity by tracking glucose use in the brain, revealing active areas as you perform tasks.
MRI scan
A brain scan using a strong magnetic field and radio waves to create detailed images of brain tissue.
fMRI (functional MRI)
A technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans.
thalamus
- receives all sensory info. except smell
- sensory switchboard
reticular formation
a network of neuron fibers involved in attention, arousal & alertness
pons
coordinates movement
medulla
- the base of the brainstem
- controls heartbeat & breathing
brainstem
- brain’s oldest + inter most part
- connection to spinal cord
- is a crossover point where most nerves from
each side of the brain connect to the body’s
opposite side
Cerebellum
coordinates voluntary movement (w/ assistance from the pons)
enables nonverbal learning & memory
helps us judge time, modulate our emotions & discriminate sounds + textures
which system lies in between the oldest & newest brain areas?
the limbic system
what does the limbic system contain?
- hippocampus
- pituitary gland
- amygdala
- hypothalamus
hippocampus
- this processes conscious memories
- doesn’t store memories, it just seems to help
create them - converts short-term memory into long-term
memory
Amygdala
involved in memory and emotion, particularly fear and aggression.
Hypothalamus
- an imp. link in the command chain governing
bodily maintenance - helps govern the endocrine system via the
pituitary gland - is linked to emotion and reward.
Frontal lobe
controls voluntary movement, planning, decision-making & problem-solving
Parietal lobe
- processes sensory info. such as touch,
temperature & pain - imp. for mathematical & spatial reasoning
Occipital lobe (+ visual cortex)
responsible for visual processing
Temporal Lobe (+ auditory cortex)
involving in hearing, memory + language comprehension
Somatosensory cortex
area at the front of the parietal lobes that registers and processes body touch and movement sensations
Left Hemisphere: 4 Lobes
F.P.O.T
- frontal
- parietal
- occipital
- temporal
Association Areas
regions that integrate info. from different sensory & motor areas to help with higher-level functions such as SLRT (speaking, learning, remembering, thinking).
What can damage to the frontal lobe cause & how may people act?
- can alter personality
- reduce inhibitions
- affect moral judgement
- ppl may act impulsively without considering the
emotional impact of their actions.
List the purpose of the right-temporal lobe & if damaged, what can happen.
- critical for recognizing faces
- damage here means you can describe features
but cannot identify the person
What do higher mental functions & language acquisition depend on?
it depends on the integration of specialized neural networks across different areas of the brain
what does damage to Broca’s area disrupt?
speaking
what does damage to Wernicke’s area disrupt?
understanding
The Brain’s Plasticity
plasticity referring to its ability to modify itself after damage
What did Gazzaniga’s experiment reveal about the left & right hemisphere?
left hemisphere –> speech
right hemisphere –> can understand, not speak
List 4 things the Right Hemisphere is responsible for.
- perceptual tasks
- make inferences – linguistic nuances (tone,
meaning, or word choice) - helps modulate our speech in a way that makes
sense - helps form our sense of self
List 4 things the Left Hemisphere is responsible for.
- literal interpretations of speech
- calculations
- speech processing
- quick, literal interpretations of language
Dual Processing
1) Effort Processing: the sensory info. you take an
effort to learn
2) Auto Processing: the sensory info. you process
unintentionally
Neurotransmitters vs. Hormones
Neurotransmitters
- in nervous system
- you find them floating in synapses & axon
terminals
- modulate N.S activities such as mood, sleep,
learning & muscle control
- examples: GASD (GABA, Acetylcholine,
Serotonin, Dopamine)
Hormones
- in endocrine system
- released by glands & they’re floating around
throughout bloodstream
- regulate metabolism, growth & mood
- examples: TEACI (Testosterone, Estrogen,
Adrenaline, Cortisol, Insulin)
Pituitary Gland
The endocrine system’s most influential gland.
Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands.
Leptin
A hormone produced by adipose (fat) cells regulates energy balance by inhibiting hunger
Ghrelin
- secreted form: stomach
- function: stimulates appetite, increases food
intake + promotes fat storage
Melatonin
A hormone manufactured by the pineal gland that regulates sleep-wake cycles & circadian rhythms.
Oxytocin
A hormone released by the hypothalamus that facilities childbirth, breast-feeding & social bonding.
Psychoactive drugs
chemicals that change how we think (perception) & feel (moods).
Tolerance
when a person needs more of a drug to feel the same effect because their body gets used to it.
Depressants
drugs, such as alcohol, barbiturates (also known as tranquilizers) & opiates, that calm neural activity & slow body functions
Stimulants
drugs, such as caffeine, nicotine, amphetamines, cocaine, methamphetamine, ecstasy, excites neural activity & speeds up body functions.
Nicotine
- one of the most addictive stimulants
- eliminating smoke would increase life
expectancy more than any other preventive
measure
Cocaine
- the recipe for Coca-Cola orginally included an
extract of the coca plant, creating a cocaine
tonic for tired, elderly people - is snorted, injected, or smoked, entering the
bloodstream quickly & causing a rush of
euphoria - this euphoria depletes the brain’s dopamine,
serotonin & norepinephrine (because cocaine
blocks re-uptake of dopamine), leading to a
crash of agitated depression within an hour - in aggressive situations, cocaine can heighten
reactions
Methamphetamine
chemically related to its parent drug, amphetamine, but has even greater effects.
- triggers the release of dopamine, which
stimulates brain cells that enhance energy &
mood, leading to 8 hours or so of heightened
energy & euphoria - over time, meth may reduce baseline dopamine
levels, leaving the user with depressed
functioning.
Ecstasy (street name for MDMA)
- type of stimulant
- triggers dopamine release, but its major effect is
releasing stored serotonin & blocking its re-
uptake. This can damage serotonin-producing
neurons leading to permanent depression. - impairs memory, slows thought & disturbs sleep
by interfering with serotonin’s control of
circadan rhythm.
Hallucinogens & list its types
- distorts perceptions & evoke sensory images in
the absence of sensory input which is why these
drugs are also called psychedelics, meaning
“mind-manifesting”. - Lysergic Acid Diethylamide (LSD)
- marijuana
- psilocybin (shrooms or magic mushrooms)
circadian rhythm
the biological clock; regular bodily rhythms that occur on a 24-hour cycle
How does the pineal gland regulate melatonin production in the morning & evening?
morning: decreases (promotes wakefulness)
evening: increases (induces sleep)
NREM-1
- very light sleep
- duration: few minutes
- EEG waves: theta waves
NREM-2
- characterized by periodic sleep spindles –
bursts of rapid, rhythmic brain – wave activity - clearly asleep but can still be awakened easily
- duration: 20 mins
- EEG waves: theta waves w/ sleep spindles
NREM-3
- the deepest stage of sleep
- gets shorter throughout the night
- sleepwalking & sleep talking
- delta waves
- duration: about 30 mins
REM Sleep
- brain waves become rapid & saw-toothed
- eye movements signal the beginning of dreams
- you’re sound asleep, but internally you’re very
much awake - vivid dreaming
- nightmares
REM Rebound
Something that can happen when REM is suppressed by medication or by sleep disorders, when it comes back, it can return stronger than before & even might have nightmares.
Sleep deprivation & its causes
a condition characterized by inadequate or insufficient sleep sustained over a period of time.
It can cause:
- increases in gherlin, a hunger-arousing hormone
- increases in cortisol, a stress hormone that
stimulates the body to make fat & causes
inflammation in the body
Insomnia
a sleep disorder characterized by difficulty falling asleep, staying asleep, or both.
Narcolepsy & its causes
a sleep disorder that disrupts sleep-wake processes.
- this can cause excessive sleepiness & make it
hard for people w/ narcolepsy to stay awake for
long periods of time.
Sleep paralysis
people w/ narcolepsy have a higher rate of sleep paralysis, which is a feeling of being unable to move that occurs while falling asleep or waking up.
Cataplexy
a sudden loss in muscle control
Sleep Apnea
a common sleep disorder that causes frequent pauses in breathing during sleep.
What’s somnabulism?
Sleepwalking
Transduction
conversion of one form of energy into another.
In sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brains can interpret.
Sensation
the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment
Absolute Threshold
the minimum stimulation needed to detect a particular stimulus 50% of the time
Just noticeable difference
difference in stimuli required to detect a difference between the stimuli
Sensory adaptation
diminished sensitivity as a consequence of constant stimulation
Weber’s Law
the principle that, to be perceived as different, 2 stimuli must differ by a constant minimum percentage (rather than a constant amount)
Sensory interaction
our senses all work together to help us make sense of the world
Synesthesia
when 1 sense is working, the other is triggered with it
Retina
the light-sensitive inner surface of the eye, containing the receptor rods & cones plus layers of neurons that begin the processing of visual information
Blind Spot
the point at which the optic nerve leaves the eye, creating a “blind” spot because no receptor cells are located there
Visual nerve
carries the visual impulse out the back of the eye and into the brain for further processing.
Accommodation
the process by which the eye’s lens changes shape to focus near or far objects on the retina
Lens
the transparent structure behind the pupil that changes shape to help focus images on the retina
Nearsightedness (Myopia)
A refractive error where far-away objects appear blurry. Light focuses in front of the retina.
Farsightedness (Hyperopia)
A refractive error where nearby objects appear blurry. Light focuses behind the retina.
Color Blindness
A condition where individuals see colors differently than most people.
Prosopagnosia (Face Blindness)
Inability to recognize faces.
Blindsight
Neurological condition where a person can perceive the location of objects despite being cortically blind.
Monochromatism
seeing colors as shades of grey due to the absence of functional cone pigments.
Dichromatism
Partial color blindness where the eye has only 2 types of cone photopigments.
Protanopia
A type of red-green color blindness where there’s a deficiency in perceiving red.
Deuteranopia
A type of red-green color blindness where there’s a deficiency in perceiving green.
Tritanomaly
A type of blue-yellow color blindness where there’s a deficiency in perceiving blue.
Photoreceptors
Specialized light-sensitive neurons in the retina that convert light into neural impulses; includes rods and cones
Tritanopia
A type of blue-yellow color blindness where there’s a deficiency in perceiving yellow.
Rods
retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don’t respond
Cones
retinal receptor cells that are concentrated near the center of the retina & that function in daylight or in well-lit conditions.
The cones detect fine detail & give rise to color sensations.
Trichromatic theory
theory of color vision that proposes 3 types of cones: red, blue, and green
Opponent-Process theory
the theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision.
For example, some cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green
Afterimages
images that occur when a visual sensation persists for a brief time even after the original stimulus is removed
Ganglion Cells
In the retina, the specialized neurons that connect to the bipolar cells; the bundled axons of the ganglion cells form the optic nerve.
Wavelength
the distance from the peak of one light or sound wave to the peak of the next.
Pitch
a tone’s experienced highness or lowness; depends on frequency
Amplitude
the intensity or amount of energy of a wave, reflected in the height of the wave; determines a sound’s loudness.
loudness
a sound’s intensity
Pitch perception
the aspect of hearing that allows us to tell how high or low a given tone is
Place theory
presumes that we hear different pitches because different sound waves trigger activity at different places along the cochlea’s basilar membrane.
Volley theory
the ear converts sound into nerve signals for frequencies by using group of neurons. These neurons fire in turns, slightly out of sync, to create a stream of impulses faster than any single neuron could.
- this is like a group of archers taking turns shooting arrows, so they hit the target more frequently than 1 archer could alone.
Sound localization
the process by which the location of sound is determined
conduction deafness
An inability to hear resulting from damage to structures of the middle or inner ear.
sensorineural deafness
deafness that results from damage to the auditory nerve
Olfactory system
the sensory system for smell
Phantom-limb pain
this happens when amputees experience pain in the limb that no longer exists.
gate control theory
the theory that the spinal cord contains a neurological “gate” that blocks pain signals or allows them to pass on to the brain.
The “gate” is opened by the activity of pain signals traveling up small nerve fibers & is closed by activity in larger fibers or by information coming from the brain.
What’s 1 way to treat chronic pain?
to stimulate (by massage, electric stimulation, or acupuncture) “gate-closing” activity in the large neural fibers.
List 5 taste sensations
sweet, salty, sour, bitter, umami, oleogustus
supertasters
people with heightened sensitivity to all tastes and mouth sensations
medium tasters
50% of people have this level of taste sensitivity
nontasters
people who cannot detect bitter compounds except at very high concentrations
When we eat, how does smell & taste work together?
Food releases chemicals that reach our taste buds & olfactory receptors, combining to form the perception of flavor.
Important sensors in your joints, tendons & muscles enable your kinesthesia. What’s meant by the latter?
kinesthesia keeps you aware of your body parts’ position & movement.
Vision interacts with kinesthesia. This works with the vestibular sense. What’s meant by the latter?
The vestibular sense monitors the head’s position & movement.
Semicircular canals
fluid-filled structures in the inner ear that detect head movement
