8 Methods in Neuroscience Free Online FlashCards

What does electrophysiology measure?

Electrophysiology uses electrodes to measure electrical signals in the nervous system.

What can patch-clamp recording measure in a single neuron?

A fine glass pipette measures voltage across one neuron's membrane or current flowing through it, providing detailed information about its electrical properties.

What can arrays of extracellular electrodes record?

They record activity from neurons near the electrode. Arrays can capture spike times from many neurons and slower local field potentials reflecting groups of cells.

What signals do EEG and MEG detect?

EEG records voltage differences at the scalp, while MEG detects magnetic fields produced by brain activity.

What is a key limitation shared by EEG and MEG?

Both are noninvasive and provide excellent temporal information, but their signals combine activity from many neurons and do not directly record individual neurons' spikes.

How do structural MRI and fMRI differ?

Structural MRI depicts anatomy. Functional MRI commonly maps the blood-oxygen-level-dependent (BOLD) signal associated with neural activity.

What does the fMRI BOLD signal indicate, and what can it not prove alone?

BOLD reflects changes in blood oxygenation and flow associated with neural activity. It is indirect and relatively slow, and a task-related signal alone does not prove that a region causes the behavior.

How does calcium imaging indicate neuronal activity?

Fluorescent indicators change brightness with intracellular calcium, which often follows neuronal activity. The signals can track many identified cells but are generally slower than electrical spikes.

What can lesions or inactivation test, and what are two caveats?

Damaging or temporarily suppressing a brain area can test whether it is necessary for a task. Nearby tissue may also be affected, or the brain may adapt.

What is a limitation of electrical stimulation?

Electrical stimulation activates neural tissue, but may recruit multiple cell types and nearby fibers.

How does optogenetics control selected neural cells?

Optogenetics uses genetic tools to make selected cells responsive to light, enabling relatively rapid, targeted activation or inhibition. It commonly requires genetic delivery and light access to tissue.

How does perturbing neural activity strengthen a causal claim?

A change in neural activity alongside a stimulus or behavior shows an association, not necessarily a cause. Changing neural activity and measuring the outcome helps test whether it contributes causally.