Ferret LGN


    1. Do ferret LGN cells exhibit orientation or direction selectivity for the stimuli we use in cortex? For their optimal temporal and spatial frequencies?

    2. What is the latency/reliability of LGN cells?

    3. What is the receptive field shape of these cells?

    4. With motion training, how do these quantities change? (Bidirectional or unidirectional??? Darn it, both are interesting.)

      1. Bidirectional motion is most "natural"

      2. There is some concern that unidirectional training might alter the retina; this would be the perfect test

    5. Test Glider stims for James Fitzgerald

    6. What device should we use to record cells?

      1. Tetrodes??

      2. 32 channel Neuronexus probes?? Cris Niel's group did this in mouse

      3. Some Swadlow thing??


    1. Stimuli for assessing orientation/direction selectivity

      1. Direction tuning curve (spatial frequency 0.08 and temporal frequency 4Hz), 5 reps, 30 degree steps

      2. Spatial frequency tuning (using optimal orientation from above)

      3. Temporal frequency tuning

      4. Direction tuning curve (optimal spatial and temporal frequency), 5 reps, 30 degree steps

      5. OR, direction tuning curve at a few spatial frequencies and temporal frequencies?

    2. Receptive field shape:

      1. Reverse correlation (dense noise)

    1. Latency/reliability

      1. Spots of different sizes, contrast (white or black), flashed at different spots on the screen (250ms each spot), 30 reps each (this is a long stimulus)

      2. OR, spatial phase tuning, square wave grating w/ square wave animation (1-d search space, but would it give good responses??)

      3. OR, spatial phase tuning with a sinusoidal grating (would allow identification of X and Y cells)

        1. Spatial phase tuning at optimal SF

        2. Spatial phase tuning at 2x optimal SF

        3. Spatial phase tuning at 3x optimal SF

    1. Glider stimulation