Test 2 Flashcards
Nervous system
The body’s system that handles processing info, sending electrochemical signals throughout the body using billions of neurons. It regulates the communication of information
Peripheral nervous system
nerves that connect the central nervous system to organs and muscles
Somatic nervous system
in charge of voluntary actions, it passes commands from CNS to skeletal muscle. As well as conveying sensory information to the CNS.
Autonomic nervous system
in charge of involuntary actions and passes CNS commands to blood vessels, internal organs and glands
Sympathetic system
fight or flight response, used when there is a conflict or threat
Parasympathetic system
rest or digest response, conserves energy and helps with digestion
Spinal cord
relays information between the brain and the PNS and controls spinal reflexes
Spinal reflexes
motor movements made without consulting the brain
Glial cells
helper cells; dispose of dead neurons, feed them, and are in charge of protection. Their insulation is myelin
Neuron
specialized nerve cells that receive and transmit info. Made of; cell body, dendrites, and an axon
Nucleus
contains chromosomes with our DNA
Cell body (Soma)
cell body that keeps the neuron alive. It synthesizes neurotransmitters and coordinates information
Dendrites
branch off soma and pass info to it, receives info from other neurons. It is covered in synapse receptors
Axon
elongated fiber off soma, conducting info from it to neurons, muscles, glands. The neural impulse goes in a one way direction in neuron
Myelin sheath
insulation around some axons, which speeds up signal travel. Made up by glial cells
Axon terminal
knob like endings, end at synapses. Contain vesicles with neurotransmitters that carry info to other neurons/cells
Action potential
an electric signal that sends info along the axon. Only triggered if total strength of all incoming signals from dendrites exceeds a firing threshold (all-or-none)
Demyelinating disease
When the myelin sheath is damaged; neural signals are slowed and distorted, axon deteriorates/is lost, neurological problems arise and movement, sensations, cognitions, internal organs are all impacted.
Synapse
Microscopic junction between axon terminals of the sending neuron and dendrites or soma of the receiving neuron. Transmission of signal between neurons
Neurotransmitters
A chemical messenger that carries the signal across the synaptic gap, to a receiving neuron’s dendrites. Excitatory action boosts the signal, inhibitory does the opposite
Endorphin
Natural pain killer-has a calm drowsy effect
Dopamine
regulates voluntary movement, attention/working memory and motivation
Norepinephrine
involved in fight or flight response. Talks to ANS
Serotonin
stabilizes our mood (well-being) and is important with sleeping and eating
Glutamate
common throughout the NS and help with brain development (learning & memory). Too much can result in seizures
GABA
is an inhibitor and can assist with anxiety (also counteracts glutamate)
Acetylcholine
affects movement in muscles and low levels can cause Alzheimer’s
Direct agonists
Imitate the actions of the neurotransmitters (producing the same effect) e.g. opioids in treating endorphins
Indirect agonists
Enhance the (synthesis, stimuli, removal) action of the neurotransmitter (stronger, longer effect) e.g. cocaine
Agonists
mimic/ enhance neurotransmitter effects
Antagonists
block or inhibit neurotransmitter effects
Direct antagonists
Prevents the actions of the neurotransmitter (block the effect) e.g. naloxone against opioids
Indirect antagonists
Inhibits the actions of the neurotransmitter (stimulus, release, removal) actions creating a weaker shorter effect e.g. botulinum toxin against acetylcholine
Fore brain
the largest structure in the brain, its outer layer is the cerebral cortex. The core of the subcortical structures and has 2 hemispheres divided by corpus callosum
Midbrain
Made of tectum (uses sensory input to orient body with stimuli) and tegmentum (involved in movement and arousal).
Hindbrain “reptilian”
in charge of basic life functions and coordinates info passing to and from the spine. Involuntary visceral things
Medulla (hindbrain)
Extension of the spinal cord, an controls all vital functions (breathing, HR, BP). Damage to this area will kill you
Reticular formation (RF) (hindbrain)
Regulates sleep and wakefulness
Cerebellum “little brain” (hindbrain)
Controls fine motor skills and coordination of movement (intoxication affects this part)
Pons “bridge” (hindbrain)
relays info between the cerebellum and the rest of the brain. Involved in movement
Basal ganglia (forebrain)
a set of structures that directs intentional movements an posture. Interfaces with motor cortex, midbrain, cerebellum
Thalamus (forebrain)
filters and transmits sensory information to various parts of the cortex (decides what is passed on)
cerebral cortex
sheet of neural tissue that is outermost to both hemispheres, each hemisphere has 4 lobes in charge of the most complex behaviours
Hypothalamus (forebrain)
Connects the brain to the endocrine system via pituitary gland. Regulates biological needs and controls the ANS
Limbic system
a loose network of structures and is involved in motivation, emotion, learning and memory. It is where subcortical structures interface with cortex
Hippocampus (forebrain)
is in charge of learning and memory. Consolidates new factual memories into long-term storage
Amygdala (forebrain)
in charge of emotional processes and attaches significance to previously neutral events (learning fear/reward responses)
Motor cortex (frontal lobe)
controls initiation of voluntary movement. Sends commands to; basal ganglia, midbrain, pons, cerebellum and spinal cord
prefrontal cortex (frontal lobe)
executive control system, it; monitors, organizes, integrates and directs. It is in charge of higher-order mental functions
Parietal lobe
It processes inputs from the skin via the thalamus
Temporal lobe
Makes sense of primary information (hearing, language, etc). Primary auditory cortex
Occipital lobe
Primary visual cortex. Makes sense of other primary info (interpretation, recognition) and is located at the back of the brain
Sensory homunculus (parietal lobe)
each area of somatosensory cortex maps onto a specific part of the body (opposite side)
Wernicke’s area (left temporal lobe)
damage can make one lose their ability to understand spoken language. Sentences can be formed but are incoherent
Right temporal lobe
lose ability to recognize different types of sounds. Speech is flat but language comprehension is not impaired
Contralateral control
each hem. controls functions on the opposite side of the body
Corpus callosum
band of nerve fibers that passes info across hem.’s
Lateral specialization
differential functions of the left and right hem.’s
Neuroplasticity
the ability of the brain to re-write itself in response to experience
Hebb’s learning rule
neural circuits that are repeatedly activated become stronger, faster and more sensitive
Behaviourism
all behaviour is learned through interactions with the environment (mostly animal test subjects)
Associative learning
learning that 2 events are linked together.
Classical conditioning (Ivan Pavlov)
when a neutral stimulus produces a response after being paired with a stimulus that naturally produces a response
Unconditioned stimulus (US)
natural trigger that reliably produces UR (not learned)
Unconditioned response (UR)
natural reflexive reaction to US (not learned)
Neutral stimulus (NS)
initially elicits no response by itself
Conditioned Stimulus (CS)
learned trigger for CR (formerly known as NS)
Conditioned response (CR)
learned response to CS (similar to UR) even without US
Stimulus generalization
when CR is extends other stimuli to the original CS without explicit paring
Stimulus discrimination
when CR is not generalized to other similar stimuli
Extinction
when CS is repeatedly experienced alone (no pairing with US), it will gradually stop eliciting CR
Operant conditioning (B.F. Skinner)
learning to associate behaviours with consequences (applies to voluntary responses)
Law-of-effect (Thorndike)
Behaviours followed by satisfying consequences will be strengthened(repeated)
and behaviours followed by unpleasant consequences will be weakened(not repeated)
Reinforcement
wanted behaviours, will be strengthened
Punishment
unwanted behaviours, will be weakened
Shaping
stepwise process of acquiring complex (unnatural) behaviours. Rewarding each small step, then only rewarding the final step
Reinforcement schedules
patterns that define when and how the correct response will be reinforced
Positive reinforcement
increases likelihood of behaviour by added something wanted
Negative reinforcement
increases likelihood of behaviour by removing something unwanted
Positive punishment
decreases likelihood of behaviour by adding something unwanted
Negative punishment
decreases likelihood of behaviour by adding something wanted
Exposure therapy
confronting the feared CS and prevent avoidance. With repeated exposure, subject will learn that CS is tolerable
Psychophysics
the study of how external stimuli are detected and translated into internal experiences
Absolute threshold
the smallest amount of stimulation needed to detect a stimulus at least half the time
Sensory adaptation
sensory systems become gradually less sensitive to constant/unchanging stimulus (allows to divert attention to other stimuli)
Just noticeable difference (difference threshold)
the smallest difference in stimulation needed to detect the change at least half the time
Signal detection theory
there is no 100% detection accuracy because it depends on external and psychological factors (how effectively the perceptual system represents sensory events)
Selective attention
attention is a limited mental resource. selective spotlight on one thing at a time (focus only on relevant things)
Context effect
different contexts yield different perceptions of the same stimulus
Sensation
a bottom-up(based on experiences) process where sensory systems register raw stimuli from the world “out there”
Perception
a top-down(based on facts) process where the brain organizes, identifies and interprets the incoming sensation to form a mental representation
Transduction
physical stimuli registered by sensory receptors are converted into neural signals
Retina
neural tissue with millions of photoreceptors
Rods (retina)
a type of receptor cell which concentrates on periphery, grayscale and motion, and functioning in dark conditions
Cones (retina)
a type of receptor which concentrates on fine details, detecting colour and functioning in light conditions
Trichromatic theory of colour vision
3 types of cones with different sensitivities to different wavelengths L, M and S(perceived colour is a different mix of L,M and S cones)
Colour vision deficiency
reduced colour discrimination. one cone type is defficient/missing (dichromatic vision)
Opponent process theory of colour vision
3 pairs of neurons in the retina that work in opposition to each other
Perceptual hypothesis
assumptions the brain uses to make quick and automatic extrapolations
Gestalt principles
we perceive things as a unified whole (vs. as separate bits)
Figure and ground rule
an object is perceived as separate from its background
Proximity (grouping rule)
objects close to each other are perceived as belonging together
Similarity (grouping rule)
features that are similar are perceived as belonging together
Closure rule
completing a familiar form when it appears to have gaps
Depth perception
retinal images are in 2D but we see objects in 3D (depth and distance are not perceived)
Binocular disparity (binocular cue)
each eye receives slightly different retinal image (brain compares the two images to to judge distance)
Motion parallax based on motion (monocular cue)
objects that are closer to us move faster across projects farther in the distance
Pictorial cues from a flat picture (monocular cue)
cues about distance in a flat picture (many factors)
Spinning dancer illusion
absence of overlap cues direction of rotation appears to alternate
Ponzo illusion
identical objects appear different in size due to background
Sensory neurons
receive information from the external world and convey this information to the brain via the spinal cord.
Motor neurons
carry signals from the spinal cord to the muscles to produce movement
Interneurons
connect sensory neurons, motor neurons, or other interneurons.
conduction
the movement of an electric signal within neurons, from the dendrites to the cell body, then throughout the axon.
transmission
the movement of a signal from one neuron to another as a result of chemical signalling across the synapse.
electrochemical action
conduction and transmission together
resting potential
the difference in electric charge between the inside and outside of a neuron’s cell membrane
refractory period
the time following an action potential during which a new action potential cannot be initiated.
Nodes of Ranvier
breakpoints in the myelin sheath
saltatory conduction
the current jumps from each node of Ranvier to the next (slows down)
terminal buttons
knoblike structures at the end of an axon
Receptors
parts of the cell membrane that receive neurotransmitters and either initiate or prevent a new electric signal
Synaptic transmission
the sending and recieving of chemical neurotransmitters
reuptake
when neurotransmitters are absorbed by the terminal buttons of the presynaptic neuron’s axon or by neighbouring glial cells
enzyme deactivation
in which specific enzymes break down specific neurotransmitters
diffusion
occurs when neurotransmitters drift out of the synapse and can no longer reach receptors
autoreceptors
Neurotransmitters can also bind to receptor sites on the presynaptic neuron called
central nervous system
composed of the brain and spinal cord
reflex arc
a neural pathway that controls reflex actions
tectum (midbrain)
orients an organism in the environment.
tegmentum (midbrain)
involved in movement and arousal
endocrine system
a network of glands that produce and secrete into the bloodstream chemical messages known as hormones, which influence a wide variety of basic functions, including metabolism, growth, and sexual development
Pituitary gland
the “master gland” of the body’s hormone-producing system, which releases hormones that direct the functions of many other glands in the body
Gyri (singular: gyrus)
the smooth raised surfaces on the cerebral cortex
Sulci (singular: sulcus)
indentations or fissures on the cerebral cortex
contralateral control
your right cerebral hemisphere perceives stimuli from and controls movements on the left side of your body (vice-versa)
Commissures
bundles of axons that make possible communication between parallel areas of the cortex in each half
corpus callosum
connects large areas of the cerebral cortex on each side of the brain and supports communication of information across the hemispheres
somatosensory cortex
a strip of brain tissue running from the top of the brain down to the sides that is in charge of receiving/processing sensory info
association areas
composed of neurons that help provide sense and meaning to information registered in the cortex
mirror neurons (found in frontal lobe)
active when an animal performs a behaviour, such as reaching for or manipulating an object, and are also activated when another animal observes that animal performing the same behaviour
gene
the major unit of hereditary transmission
chromosomes
strands of DNA wound around each other in a double-helix configuration
epigenetics
the study of environmental influences that determine whether or not genes are expressed, or the degree to which they are expressed, without altering the basic DNA sequences that constitute the genes themselves
epigenetic marks
chemical modifications to DNA that can switch genes on or off
DNA methylation
adding a methyl group to DNA (high levels are correlated with stressful situations)
Histone modification
adding chemical modifications to proteins called histones that are involved in packaging DNA
Heritability
a measure of the variability of behavioural traits among individuals that can be accounted for by genetic factors
Broca’s area
area in the upper-left temporal lobe
electroencephalograph
a device used to record electrical activity in the brain
computerized axial tomography scan
a scanner rotates a device around a person’s head and takes a series of X-ray photographs from different angles showing different tissue densities
Magnetic resonance imaging
strong magnetic field to line up the nuclei of specific molecules in the brain tissue. Brief but powerful pulses of radio waves cause the nuclei to rotate out of alignment. When a pulse ends, the nuclei snap back in line with the magnetic field and give off a small amount of energy in the process
diffusion tensor imaging
visualize white matter pathways, which are fibre bundles that connect both nearby and distant brain regions to each other. DTI measures the rate and direction of diffusion or movement of water molecules, which reveal where a white matter pathway goes
positron emission tomography
radioactive substance is injected into subjects bloodstream. The brain is then scanned by radiation detectors as the person performs perceptual or cognitive tasks (more radiation=greater blood flow=use that area more)
functional magnetic resonance imaging
detects the difference between oxygenated hemoglobin and deoxygenated hemoglobin when exposed to magnetic pulses
resting state functional connectivity
the relationship of brain regions with each other
default network
a group of interconnected regions in the frontal, temporal, and parietal lobes that is involved in internally focused cognitive activities
transcranial magnetic stimulation
a benign technique, a way to mimic brain damage. Delivers a magnetic pulse that passes through the skull and deactivates neurons in the cerebral cortex for a short period
learning
acquisition, from experience, of new knowledge, skills, or responses that results in a relatively permanent change in the state of the learner
habituation
a general process in which repeated or prolonged exposure to a stimulus results in a gradual reduction in responding
sensitization
presentation of a stimulus leads to an increased response to a later stimulus
acquisition
the phase of classical conditioning when the CS and the US are presented together
second-order conditioning
a type of learning whereby a CS is paired with a stimulus that became associated with the US in an earlier procedure
biological preparedness
a propensity for learning particular kinds of associations over other kinds
Skinner box (operant conditioning chamber)
allows a researcher to study the behaviour of small organisms in a controlled environment
Primary reinforcers
Things that help satisfy biological needs or desires
Secondary reinforcers
things that derive their effectiveness from their associations with primary reinforcers through classical conditioning
Interval schedules
based on the time intervals between reinforcements
Ratio schedules
based on the ratio of responses to reinforcements
Fixed-interval schedule
reinforcers are presented at fixed time periods, provided that the appropriate response is made
Variable-interval schedule
a behaviour is reinforced on the basis of an average time that has expired since the last reinforcement
Fixed-ratio schedule
reinforcement is delivered after a specific number of responses have been made
Continuous reinforcement
presenting reinforcement after each response
Variable-ratio schedule
the delivery of reinforcement is based on a particular average number of responses
intermittent reinforcement
whereby only some of the responses made are followed by reinforcement
intermittent reinforcement effect
the fact that operant behaviours that are maintained under intermittent reinforcement schedules resist extinction better than those maintained under continuous reinforcement
Latent learning
something is learned, but it is not manifested as a behavioural change until sometime in the future
Cognitive map
a mental representation of the physical features of the environment
pleasure centers
The nucleus accumbens, medial forebrain bundle, and hypothalamus
observational learning
an organism learns by watching the actions of others
Diffusion chain
individuals initially learn a behaviour by observing another individual perform that behaviour, and then become models from which other individuals learn the behaviour
enculturation hypothesis
Being raised in a human culture has a profound effect on the cognitive abilities of chimpanzees
implicit learning
learning that takes place largely independent of awareness of both the process and the products of information acquisition (best demonstrated in people with amnesia and ASD)
sensitivity
how responsive we are to faint stimuli
Acuity
how well we can distinguish two very similar stimuli
webers law
for every sense domain, the change in a stimulus that is just noticeable is a constant ratio of the standard stimulus, over a range of standard intensities
Visual acuity
the ability to see fine detail
Cornea
Light that reaches the eyes passes first through a clear, smooth outer tissue
Pupil
after cornea bends light it is sent to a hole in the coloured part of the eye
Iris
a translucent, doughnut-shaped muscle that controls the size of the pupil and therefore the amount of light that can enter the eye
Retina
a layer of light-sensitive tissue lining the back of the eyeball
Accommodation
the process by which the eye maintains a clear image on the retina. (muscles change lens shape for different distances)
Nearsightedness (myopia)
eyeball is too long, images are focused in front of the retina
Farsightedness (hyperopia)
eyeball is too short, images are focused behind the retina
Photoreceptor cells
contain light-sensitive proteins that absorb light and transduce it into electrical signals.
Fovea
an area of the retina where vision is clearest and there are no rods at all.
Bipolar cells
top layer of neurons that collect electrical signals from the rods and cones and transmit them to the outermost layer of the retina
Retinal ganglion cells
top layer of neurons organize the signals and send them to the brain (optic nerve)
Blind spot
a location in the visual field that produces no sensation on the retina
Area V1
the part of the occipital lobe that contains the primary visual cortex.
Colour-opponent system
pairs of cone types (channels) work in opposition: the L-cone channel against the M-cone channel and the S-cone channel against the M-cone channel
Visual receptive field
the region of the visual field to which each neuron responds
Ventral stream (lower) “what” pathway
travels across the occipital lobe into the lower levels of the temporal lobes and includes brain areas that represent an object’s shape and identity
Dorsal stream (upper) “where”/”perception for action” pathway
travels up from the occipital lobe to the parietal lobes (including some of the middle and upper levels of the temporal lobes) and includes brain areas that identify where an object is and how it is moving
Binding problem
how the brain links features together so that we see unified objects in our visual world rather than free-floating or miscombined features
parallel processing
the brain’s capacity to perform many activities at the same time
Illusory conjunction
a perceptual mistake whereby the brain incorrectly combines features from multiple objects
Feature-integration theory
which holds that focused attention is not required to detect the individual features that make up a stimulus
Modular view
specialized brain areas, or modules, detect and represent faces or houses, body parts, and even other objects (b/c they differ in properties)
perceptual consistancy
even as aspects of sensory signals change, perception remains constant.
perceptual contrast
although the sensory information from two things may be very similar, we perceive the objects as different
Perceptual organization
process of grouping and segregating features to create whole objects organized in meaningful ways
Gestault perceptual grouping principles
simplicity, continuity, common fate, closure, similarity, proximity
Monocular depth cue
aspects of a scene that yield information about depth when viewed with only one eye
spatial acuity
ability to distinguish two features that are very close together in space
temporal acuity
ability to distinguish two features that are very close together in time
Change blindness
when people fail to detect changes to the visual details of a scene
Inattention blindness
failure to perceive objects that are not the focus of attention
Pinna
visible part of the ear on the outside of the head
eardrum
an airtight flap of skin that vibrates in response to sound waves gathered by the pinna and channelled into the auditory canal
Hammer (ossicle)
named for appearance the ossicles fit together into a lever that mechanically transmits and amplifies vibrations from the eardrum to the inner ear
Anvil (ossicle)
named for appearance the ossicles fit together into a lever that mechanically transmits and amplifies vibrations from the eardrum to the inner ear
Stirup (ossicle)
named for appearance the ossicles fit together into a lever that mechanically transmits and amplifies vibrations from the eardrum to the inner ear
Cochlea
fluid-filled tube containing cells that transduce sound vibrations into neural impulses
basilar membrane
structure in the inner ear that moves up and down in time with vibrations relayed from the ossicles, transmitted through the oval window
Inner hair cells
specialized auditory receptor neurons embedded in the basilar membrane
Area A1
the primary auditory cortex in the temporal lobe
Place code
the brain uses information about the relative activity of hair cells across the whole basilar membrane to help determine the pitch you hear
Temporal code
the brain uses the timing of the action potentials in the auditory nerve to help determine the pitch you hear
Haptic perception
active exploration of the environment by touching and grasping objects with our hands
Tactile receptive field
Each receptor is sensitive to a small patch of skin
referred pain
sensory information from internal and external areas converges on the same nerve cells in the spinal cord
gate-control theory
signals arriving from pain receptors in the body can be stopped, or gated, by interneurons in the spinal cord via feedback from the skin or from the brain
proprioception
your sense of body position
vestibular system
three fluid-filled semicircular canals and adjacent organs located next to the cochlea in each inner ear
Olfactory receptor neurons
receptor cells that transduce odourant molecules into neural impulses (in olfactory epithelium)
olfactory bulb
a brain structure located above the nasal cavity beneath the frontal lobes
pheromones
biochemical odourants emitted by other members of an animal’s species that can affect its behaviour or physiology
Direct criterion
(signal detection theory-if something is present or not) hit, miss, false alarm and correct rejection
Frontal lobe
performs tasks that help make us fully human: thinking, planning, judging, perceiving, and behaving purposefully and voluntarily.
