Cognitive Neuroscience Exam 1

Soma

Neuron cell body

Dendrite

Receives synaptic inputs

Axon hillock

Region where membrane potentials are integrated and action potentials can begin

Axon

Carries action potentials away from soma

Axon terminal

Presynaptic ending that releases neurotransmitter

Synapse

Specialized junction where cells communicate

Synaptic cleft

Gap between cells at a chemical synapse

Vesicle

Stores neurotransmitter in presynaptic terminal

Resting membrane potential

Voltage across membrane at rest; ~−70 mV in lecture

Depolarization

Membrane becomes less negative

Hyperpolarization

Membrane becomes more negative

Threshold

Membrane potential that triggers an action potential; ~−55 mV

Action potential

Regenerative electrical signal propagated along an axon

Refractory period

Period following AP when firing is impossible or harder

Myelin

Fatty insulating material surrounding axons

Node of Ranvier

Gap between myelin segments

Saltatory conduction

AP propagation by regeneration at nodes

Neurotransmitter

Chemical messenger released at synapse

Ion channel

Membrane protein allowing selected ions across

Ion pump

Protein actively moving ions against their gradients

Cognitive neuroscience

Study of how the brain enables thought

Localizationism

Particular functions depend disproportionately on particular brain areas

Aggregate field theory

Mental functions are supported by the brain acting as a whole

Phrenology

Invalid theory that skull shape reveals intellectual/personality traits

Topographic organization

Systematic spatial mapping of information, such as body parts across cortex

Syncytium

Continuous mass of tissue sharing cytoplasm

Neuron doctrine

Nervous system consists of individual neurons

Cytoarchitectonics

Studying/dividing brain regions based on cellular structure and organization

Associationism

Experience and learned associations determine mental development

Behaviorism

Psychology should emphasize observable behavior and environmental learning

Empiricism

Knowledge comes from sensory experience

Rationalism

Knowledge can be attained through reasoning

Montreal procedure

Penfield/Jasper epilepsy surgery identifying and destroying seizure-producing tissue

Description

What happened or what did we measure?

Prediction

What will happen?

Explanation

How or why did it happen?

Mechanism

A system in which interacting parts produce a phenomenon.

Pathway

A sequence tracking the flow of something through a system.

Triggering cause

Starts a process.

Structuring cause

Determines how a process unfolds.

fMRI

Measures blood-oxygen changes related to neural activity

EEG

Measures electrical activity of the brain using electrodes on the scalp

Absolute refractory period

Time during which no new action potential can be initiated regardless of stimulus strength

Relative refractory period

Period when a stronger-than-usual stimulus is needed to trigger an action potential

EPSP

Depolarizing postsynaptic potential that makes a neuron more likely to fire

IPSP

Hyperpolarizing postsynaptic potential that makes a neuron less likely to fire

Passive channel vs gated channel

Always open vs opens under specific condition

Ligand-gated vs voltage-gated

Chemical binding vs membrane voltage

Concentration gradient vs electrical gradient

Diffusion force vs charge force

Depolarization vs hyperpolarization

Less negative vs more negative

EPSP vs IPSP

Raises vs lowers probability of firing

Absolute vs relative refractory

Impossible to fire vs harder to fire

Chemical vs electrical synapse

Neurotransmitter/cleft vs gap junction/direct current

Gray vs white matter

Cell bodies vs myelinated axons

CNS vs PNS

Brain/spinal cord vs nerves outside

Sympathetic vs parasympathetic

Fight-or-flight vs rest/digest

Cerebellum

Coordination / smooth movement

Thalamus

Relay for almost all sensory information except olfaction

Hypothalamus

Homeostasis, autonomic + endocrine regulation

Hippocampus

Learning and memory

Amygdala

Emotional processing

Basal ganglia

Action selection, motor control, learning/reward

Brainstem

Sensory/motor nuclei, pathways, widespread neurotransmitter systems

Frontal lobe

Motor control, planning/decision-making/executive functions

Parietal lobe

Somatosensation, spatial processing/attention

Temporal lobe

Auditory processing, object/conceptual processing, language, medial temporal memory structures

Occipital lobe

Vision

Mental representation

Internal representation of information

Independent variable

Variable researcher manipulates

Dependent variable

Outcome researcher measures

Serial processing

Processing items one after another

Parallel processing

Processing multiple things simultaneously

Stroop effect

Automatic word processing interferes with naming ink color

Single dissociation

One function impaired while another is spared

Double dissociation

Opposite selective impairments demonstrating functional independence

Agonist

Mimics/enhances neurotransmitter action

Antagonist

Blocks/dampens neurotransmitter action

Knockout

Preventing a gene from being expressed

DBS

Implanted electrodes stimulate deep brain structures

Optogenetics

Light-sensitive proteins allow neurons to be controlled with light

TMS

Magnetic stimulation of cortical neurons

Virtual lesion

Temporary disruption produced by TMS

tDCS

Constant low electrical current through scalp

tACS

Oscillating electrical stimulation

tFUS

Focused ultrasound used to alter neural activity

CT

X-ray-based 3-D structural imaging

MRI

High-resolution structural imaging using magnetic properties of tissue

DTI

MRI method mapping white-matter pathways

Isotropic diffusion

Equal diffusion in every direction

Anisotropic diffusion

Diffusion that varies by direction

Spatial resolution

Precision in where neural activity is localized

Temporal resolution

Precision in when neural activity occurs

Firing rate

Number of action potentials generated in a given time period

Electroencephalography (EEG)

Electrical recording from scalp

Event-related potential (ERP)

Analysis of EEG activity time-locked to an event

Intracranial EEG (iEEG)

Electrical recording from inside skull

Electrocorticography (ECoG)

Intracranial recording from brain surface

Local field potential (LFP)

Voltage generated by activity of nearby populations of neurons

Magnetoencephalography (MEG)

Measures neural magnetic fields

Functional magnetic resonance imaging (fMRI)

Measures blood-oxygen changes related to neural activity