Flashcards in L11 - Retina 3 Parallel Pathways Deck (12):
CASE STUDY: Monica
-65 year old
-Saw water splashing in front of her left eye
-Grade 3 Melanoma excised 4 years ago
What's her problem?
Melanoma Associated Retinopathy - antibodies produced targeting against ON BP (mGluR6 or TRPM1 channels) and loses ON BP function
-Patient loses B-wave
-Patient treated with oral prednisolone
Where does splitting of information occur first?
At the first synapse (Ph->BCs)
Two types of GC
M-GC (5-10% of all GC): motion, LARGE receptive fields -> low spatial res
P-GC: colour, visual acuity, small receptive fields -> high spatial res
iGluR are excit/inhibit? mGluR6 are excit/inhibit?
iGluR - excit
mGluR6 (only found in retina) - inhibit
OFF cells are de/hyperpol by light? What R?
ON cells are de/hyperpol by light? What R?
What is the difference when comparing the synapses of Ph -> BPs and BP->GCs?
BP-> GC ONLY uses iGluRs (NMDA, AMPA, Kainate)
What channel is important in ON BP?
TRPM1 (transient receptor potential melanocyte) channel
Receptive field of GC has a centre and an antagonistic surround. What does this mean?
Centre of GC does one thing, surround does opposite
What creates the "surround" response?
Why are edges so important to GC?
Red and green GC communicate edges to the brain - they only fire when there are edges present