Controlling neural circuits

Question 1

The primary visual pathway – and the modulatory inputs that control it

arise from
form what?

example?

Answer 1

modulatory inputs arising primarily from the brainstem
forming widespread, sparse connections

e.g. Modulatory pathways control the sleep-wake cycle

Question 2

AWAKE

what relay visual info? to where?
supported by?

Answer 2

Thalamic cells relay visual information to the cortex

supported by brainstem inputs hence modulatory pathway

Question 3

Falling Asleep

Answer 3

Modulatory inputs turn down and switch off

Question 4

Asleep

Answer 4

Thalamic cells become insensitive to retinal input

Question 5

Modulatory inputs and attention and memory

what does modulation control?
use what receptors?

Answer 5

Modulation controls how neurones respond to specific inputs, without altering the information being processed

The modulatory inputs use metabotropic receptors

Question 6

Key characteristics of modulatory pathways

Modulatory pathways depend on signals that have (3)

Answer 6

Modulatory pathways depend on signals that have:
Diffuse, imprecise connections
Slow, persistent synapses (use metabotropic receptors)
Non-time-dependent, information-poor signals
Activity that is linked to:
changes from sleep to waking
changes in the level of concentration and attention
mental state

** Think of modulatory pathways as volume controls **