Cognitive Neuroscience Ch 3

Cognitive psychologists seek to identify

internal processes that underlie observable behavior

Key concept of experimental designs used to test mental operations

information processing depends on mental representations

Key concept of experimental designs used to test mental operations

mental representations undergo internal transformation

Mental representation

a representation of information in the mind such as an idea image or concept

Mental representation examples

belief, thoughts, concepts, desires, and perception

Stages of memory

Sensory memory, short-term memory, long-term memory

Sternberg’s memory task steps 1-4

1. Encoding 2. comparing 3. deciding 4. responding

Word superior effect

People recognize letters better when they are presented within words than when they are presented with non-word strings

Stroop task

tests how fast someone can name a color that is a different color font

Task-specific constraints

people can perform only a limited amount of internal processing at any given time which leads to this

Double dissociation

provides neuropsychological evidence that a patient has a selective deficit in a particular cognitive function

Single dissociation

When one brain lesion impairs something that disrupts a specific task but it doesn’t lead to failure of the entire process.

Agonist

A chemical substance that binds to and activates a receptor, producing a response

Antagonist

a chemical substance that binds to a receptor and blocks its activation, reducing a response

Behavioral genetics

a field that studies how genetic factors and environmental facts influence behavior

Knockout procedure

a technique used to inactivate or disable a specific gene to examine its effects on behavior or other biological functions

Deep brain stimulation

a surgical procedure where electrodes are implanted in specific areas of the brain to deliver electrical stimulation and alter neural activity

optogenetics

a technique that uses light to selectively manipulate neuronal activity

Viral transduction

a harmless engineered viral used to deliver a specific piece of DNA into target neurons

Opsins

light-sensitive proteins

what happens when opsin are exposed to a specific wavelength of light?

the opsin proteins open or close ion channels allowing researchers to activate or inhibit neuronal activity

Transcranial Magnetic Stimulation

applies a magnetic field to a specific region of the scalp to temporarily alter neural activity in the underlying brain region (virtual lesion)

Repetitive Transcranial magnetic stimulation

repeated low frequency of 1Hz bursts over 15 minutes (inhibitory effect)

Continuous-theta burst stimulation

High frequency (10Hz) for 40 seconds (excitatory effect)

Transcranial magnetic stimulation has the greatest impact on what areas

surface cortical areas

Transcranial Direct Current Stimulation

constant, low electrical current

Transcranial Alternating current stimulation

alternating electrical current

Transcranial static magnetic stimulation

strong static magnetic field

Transcranial focused ultrasound

focused, low intensity low frequency ultrasound waves

Magnetoencephalography

measures the magnetic fields produced by electrical activity in the brain

TorF

magnetic fields are more strongly detected when neural currents flow tangentially to the scalp

Positron Emission Tonography

measurement of metabolic activity by monitoring the distribution of an injected radioactive tracer as it decays

Functional Magnetic Resonance Imaging

measure of blood oxygenation level-dependent (BOLD) signal; it is indirect and only sees changes in local blood flow and oxygen consumption

Blood oxygenation level dependent signal

the ratio of oxygenated vs deoxygenated hemoglobin

Magnetic resonance spectroscopy

measures the chemical composition of brain tissue in vivo and estimates the concentrations of specific neurochemicals and metabolites within brain regions

Connectomes

structural or functional connections with the brain

structural connectome

describes physical connections between brain regions

functional connectomes

describes patterns of correlated activity between brain regions

computational neuroscience

an interdisciplinary field that develops, stimulates, and analyzes models and theories of neural function across multiple levels (from molecules and neurons to neural networks, cognition, and behavior)

Computational neuroscience develops

explicit, testable theories of cognition and neural function