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Physiology & Science: Neuroscience I > Information processing in the NS > Flashcards

Flashcards in Information processing in the NS Deck (14)
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1

Are the things we see 100% real?

What you see is a reconstruction of what MIGHT be out there, it's your brain's best guess of all that incoming neural activity. Neural activity has meaning.

2

Which parts of the brain encode information for:
i) object movement
ii) colour
iii) obejct identity 

  1. movement - parietal visual areas
  2. colour processing - cortical area
  3. identity - inferotemporal visual areas

3

What determines the firing pattern of an individual cell?

Synaptic integration

4

What is pre-synaptic inhibition and its effects?

When an inhibitory neurone terminates on a pre-synaptic bouton of an excitatory neurone. - if excitatory alone activates -> EPSP - if inhibitory activates (on excitatory) as well -> smaller EPSP

5

What 3 types of neuronal inputs are there on post-synaptic boutons on a dendrite?

- inhibitory - excitatory - modulatory all determine whether an action potential is triggered

6

What is convergence?

many presynaptic cells converge onto one single nerve cell (or fewer) to give input. 

7

What is divergence?

one nerve cell to synapse upon many other cells. The postsynaptic target could be within a single structure or widely separated. 

8

What is the role of modulation?

Modulatory inputs use metabotropic receptors, typically change size of response without changing message. They control the state of the system.

9

What is an example of modulation within the primary visual cortex?

Serotonin -> fewer action potentials (at diff times) ACh -> more action potentials (at diff times) Changes the VOLUME - not on-off like excitatory or inhibitory.

10

What is meaningful neural activity associated with?

SPECIFIC pathways - eg. motor, sensory, cognitive etc.

11

What do specific pathways depend on, in terms of signals?

- fast (ligand-gated) - precisely localised (topographic organisation) - time-dependent signals - highly selective responses - information-rich activity

12

What are some features of modulatory pathway signals?

- slow (g protein couple) - diffuse (not localised/precise) - not time-dependent - linked to changes in arousal (sleep-wake cycle) - linked to changes in attention - linked to changes in mental state

13

What happens when we are awake?

Thalamic cells relay sensory info to cortex - transmits signal as it is.

14

What happens when we are asleep?

Thalamic cells become insensitive to their sensory input - withdrawal of modulatory (sensory) input leads to spontaneous bursts of activity being fired by thalamic cells.