Cognitive Psych

Neuron

Cell that is specialised to receive and transmit info in the nervous system

Nerve net

A network of continuously interconnected nerve fibres (as contrasted with neural networks in which fibres are connected by synapses)

Neuron doctrine

The idea that individual cells called neurons transmit signals in the nervous system, and these cells are not continuous with other cells as proposed by nerve net theory

Cell body

The metabolic centre of the neuron; it contains mechanisms to keep the cell alive

Dendrites

Structures that branch out from the cell body to receive electrical signals from other neurons

Axon (nerve fibre)

Part of the neuron that transmits signals from the cell body to the synapse at the end of the axon

Synapse

Space between the end of an axon and the cell body or dendrite of the next axon

Neural circuit

Group of interconnected neurons that are responsible for neural processing

Receptors

Specialised neural structures that respond to environmental stimuli such as light, mechanical stimulation or chemical stimuli

Resting potential

Difference in charge between the inside and outside of a nerve fibre when the fibre is at rest (no other electrical signals are present)

Microelectrodes

Small wires that are used to record electrical signals from single neurons

Reference electrode

Used in conjunction with a recording electrode to measure the difference in the charge between the two

Nerve impulse (action potential)

An electrical response that is propagated down the length of an axon

Principle of neural representation

Everything a person experiences is based on representations in the person's nervous system

Feature detectors

Respond to specific visual features that make up environmental stimuli

Experience-dependent plasticity

Mechanism that causes an organism's neurons to develop so they respond best to the type of stimulation to which the organism has been exposed

Temporal lobe

Contains mechanisms responsible for language, memory, hearing, vision

frontal lobe

associated with reasoning, planning, parts of speech, movement, emotions, and problem solving

parietal lobe

receives sensory input for touch and body position

occipital lobe

visual processing

Hierarchal processing

Occurs in progression from lower to higher brain areas

Problem of sensory coding

Where the sensory code refers to how neurons represent various characteristics of the environment

Specificity coding

Idea that an object could be represented by the firing of a specialised neuron that responds only to that object

Population coding

Neural representation of a stimulus by the pattern of firing of a large number of neurons

Sparse coding

Neural coding based on the pattern of activity in small groups of neurons

Localisation of function

Theory that states that different areas of the brain are responsible for different behaviours, processes or activities

Cerebral cortex

intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body's ultimate control and information-processing center

Subcortical regions

lays underneath cortex - hypothalamus, thalamus, hippocampus, amygdala, basal ganglia

cortical equipotentiality

idea, popular in the early 1800s, that the brain operates as a whole, as opposed to operating based on specialized areas

Broca's area

controls language expression - an area, usually in the left frontal lobe, that directs the muscle movements involved in speech

Broca's aphasia

inability to produce speech

Wernicke's area

controls language reception - a brain area involved in language comprehension and expression; usually in the left temporal lobe

Wernicke's aphasia

inability to comprehend speech

prosopagnosia

inability to recognize faces

double dissociation

A situation in which a single dissociation can be demonstrated in one person, and the opposite type of single dissociation can be demonstrated in another person (i.e., Person 1: function A is present; function B is damaged; Person 2: function A is damaged; function B is present)

Electroencephalography (EEG)

records the electrical activity of the brain via electrodes on the scalp

Magnetoencephalography (MEG)

measures magnetic fields from the brain's natural electrical activity

Near-infrared spectroscopy (NIRS)

measures brain activity by using infrared light to determine changes in blood oxygen levels in the brain

transcranial magnetic stimulation (TMS)

places a powerful pulsed magnet over a person's scalp, which alters neuronal activity in the brain

Diffusion Tensor Imaging (DTI)

produces images of the brain that show connections among different regions

fMRI (functional magnetic resonance imaging)

reveals blood flow and, therefore, brain activity by comparing successive MRI scans. MRI scans show brain anatomy; fMRI scans show brain function

voxel

Small cube-shaped areas in the brain used in the analysis of data from brain scanning experiments

task-related fMRI

fMRI measured as a person is engaged in a specific task

fusiform face area (FFA)

Temporal lobe area specialized for face recognition

parahippocampal place area (PPA)

a region of the medial temporal cortex; involved in the perception of particular places ("scenes")

extrastriate body area (EBA)

responds specifically to pictures of bodies and parts of bodies

distributed representation

occurs when a specific cognition activates many areas of the brain

structural connectivity

the brain's 'wiring diagram' created by nerve axons that connect different brain areas

track-weighted imaging (TWI)

A technique for determining connectivity in the brain that is based on detection of how water diffuses along the length of nerve fibers

connectome

Comprehensive map of all structural connectivity (the physical wiring) in an organism's nervous system

functional connectivity

extent to which multiple brain regions function at the same time, which improves during adolescence

resting-state fMRI

fMRI response recorded when a person is at rest

resting-state functional connectivity

measures the extent to which spontaneous activity in different brain regions is correlated over time

seed location

brain location associated with carrying out a specific task

time-series response

indicates how fMRI response changes over time

test location

Resting-state fMRI measured at a location other than the seed location

Default Mode Network (DMN)

a circuit that is active during periods of unfocused thought

sensation

stimulation of sense organs

perception

becoming aware through the senses

machine learning

type of artificial intelligence that leverages massive amounts of data so that computers can improve the accuracy of actions and predictions on their own without additional programming

deep learning

type of machine learning that uses multiple layers of interconnections among data to identify patterns and improve predicted results. Deep learning most often uses a set of techniques known as neural networks and is popularly applied in tasks like speech recognition, image recognition, and computer vision

inverse projection problem

determining the object responsible for a particular image on the retina

occlusion

closure of a blood vessel due to blockage

viewpoint invariance

ability to recognize an object regardless of the viewpoint

bottom-up processing

analysis that begins with the sensory receptors and works up to the brain's integration of sensory information

top-down processing

use of preexisting knowledge to organize individual features into a unified whole

speech segmentation

ability to tell when one word ends and another begins

transitional probabilities

chances that one sound will follow another sound

statistical learning

process of learning about transitional probabilities and about other characteristics of language (occurs for vision too)

likelihood principle

we perceive the object that is most likely to have caused the pattern of stimuli we have received

unconscious inference

perceptions are the result of unconscious assumptions, or inferences, that we make about the environment

Gestalt psychologists

proposed principles governing perception, such as laws of organization, and a perceptual approach to problem solving involving restructuring

apparent movement

perception that a stationary object is moving

perceptual organisation

process of integrating sensations into meaningful perceptual units

principle of good continuation

Law of perceptual organization stating that points that, when connected, result in straight or smoothly curving lines are seen as belonging together. In addition, lines tend to be seen as following the smoothest path

Law of Pragnanz

perceptual organization will always be as regular, simple, and symmetric as possible

Principle of similarity

similar things appear to be grouped together

regularities in the environment

characteristics of environment that occur frequently

physical regularities

regularly occurring physical properties

oblique effect

people can perceive horizontals and verticals more easily than other orientations

light-from-above assumption

assumes light usually comes from above, which influences our perception of form in some situations

semantic regularities

characteristics associated with the functions carried out in different types of scenes

scene schema

knowledge of what a given scene typically contains

Bayesian inference

idea that estimation of the probability of an outcome is determined by prior probability and likelihood

prior probability

initial belief about the probability of an outcome

theory of natural selection

Darwin's theory that characteristics that enhance an animal's ability to survive and reproduce will be passed on to future generations

brain ablation

the study of the effect of removing parts of the brain in animals

object discrimination problem

task of remembering something based on shape and choosing it when presented with another item

landmark discrimination problem

task of remembering an object's location and choosing that location after a delay

'what' pathway

pathway leading from the striate cortex to the temporal lobe

'where' pathway

pathway leading from the striate cortex to the parietal lobe

perception pathway

from visual cortex to temporal lobe

action pathway

from occipital lobe to parietal lobe

mirror neurons

frontal lobe neurons that fire when performing certain actions or when observing another doing so. The brain's mirroring of another's action may enable imitation, language learning, and empathy

Mirror Neuron System (MNS)

network of cells that the brain uses to interpret and produce motor actions and emotion-related behavior

size-weight illusion

when two similar objects have the same weight but different sizes, the larger one seems lighter when they are lifted together

What approach involves research at both behavioral and physiological levels?

Levels-of-analysis approach.

Who conducted research that led to the neuron doctrine?

Ramon y Cajal.

What does the neuron doctrine state?

Individual cells called neurons transmit signals in the nervous system.

What technique can be used to record signals from neurons?

Microelectrodes.