Cognitive and computational Unit test

Hippocampus

• episodic memory encoding and retrieving

• spatial navigation

• contextual representation

Thalamus

gates information flow based on attentional state and arousal

Pulvinar

filters and routes information based on tasks and commands

Amygdala

• emotional evaluation

• salience detection

• social cognition

Caudate

Computes action values given current goals

Putamen

Associates stimuli with responses based on learned context

Nucleus Accumbens

integrates motivational state with action selection

Substantia Nigra

Signals prediction errors—what's unexpected given current expectations

Cortico-subcortical Loops

Information relay process that has information flow bidirectionally

The Canonical Equation: R

The neural response— how active the neuron becomes

The Canonical Equation: γ (gamma)

a scaling factor for overall response magnitude

The Canonical Equation: D

The driving input, the stimulus the neuron is turned to

The Canonical Equation: σ (sigma)

the “transition point” controlling when context dominates

The Dendritic Equation: V_m

Membrane potential— the neuron’s output voltage

The Dendritic Equation: g_E, g_L, g_I

Conductances— how open each channel is (excitatory, inhibitory, leak)

The Dendritic Equation: E_I, E_L, E_E

Reversal Potentials—the voltage each channel type pulls towards

The Dendritic Equation: Numerator

• weighted sum of reversal potentials

• each input’s vote on where the membrane potential should go

• weighted by how open its channels are

The Dendritic Equation: Denominator

• The sum of all open channels and how open each one is

• The Divisor

LFP (Local Field Potential)

• Electrical fields from nearby neurons

• measured with electrodes inside brain

EEG (Electroencephalography)

• measures summed electrical dipoles through he scalp

• Non-invasive millisecond timing

MEG (magnetoencephalography)

• magnetic fields outside head

• non-invasive, excellent localization

BOLD Signal (Blood Oxygen Level Dependent)

• Measure of changes in the ratio of oxygenated to deoxygenated hemoglobin in the blood near neural tissue

• reflects the input to neurons