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Frequency Responses of Rat Retinal Ganglion Cells.

Hadjinicolaou AE, Cloherty SL, Hung YS, Kameneva T, Ibbotson MR - PLoS ONE (2016)

Bottom Line: The least responsive cells were the B2 and C3 types (peaks: 2-5 Hz, cutoffs: 8-11 Hz).We found no difference between cells stratifying in the inner and outer IPL (i.e., ON and OFF cells) or between cells with large and small somas or dendritic fields.Intrinsic physiological properties (input resistance, spike width and sag) had little impact on frequency response at low frequencies, but account for 30-40% of response variability at frequencies >30 Hz.

View Article: PubMed Central - PubMed

Affiliation: National Vision Research Institute, Australian College of Optometry, Carlton, Victoria, Australia.

ABSTRACT
There are 15-20 different types of retinal ganglion cells (RGC) in the mammalian retina, each encoding different aspects of the visual scene. The mechanism by which post-synaptic signals from the retinal network generate spikes is determined by each cell's intrinsic electrical properties. Here we investigate the frequency responses of morphologically identified rat RGCs using intracellular injection of sinusoidal current waveforms, to assess their intrinsic capabilities with minimal contributions from the retinal network. Recorded cells were classified according to their morphological characteristics (A, B, C or D-type) and their stratification (inner (i), outer (o) or bistratified) in the inner plexiform layer (IPL). Most cell types had low- or band-pass frequency responses. A2, C1 and C4o cells were band-pass with peaks of 15-30 Hz and low-pass cutoffs above 56 Hz (A2 cells) and ~42 Hz (C1 and C4o cells). A1 and C2i/o cells were low-pass with peaks of 10-15 Hz (cutoffs 19-25 Hz). Bistratified D1 and D2 cells were also low-pass with peaks of 5-10 Hz (cutoffs ~16 Hz). The least responsive cells were the B2 and C3 types (peaks: 2-5 Hz, cutoffs: 8-11 Hz). We found no difference between cells stratifying in the inner and outer IPL (i.e., ON and OFF cells) or between cells with large and small somas or dendritic fields. Intrinsic physiological properties (input resistance, spike width and sag) had little impact on frequency response at low frequencies, but account for 30-40% of response variability at frequencies >30 Hz.

No MeSH data available.


Related in: MedlinePlus

Temporal responses to sinusoidal stimulus currents.(A–C) Probability of observing a spike plotted against time (i.e., cycle count) within each stimulus presentation for stimulus frequencies of 15 Hz, 30 Hz and 60 Hz, respectively. Spike probability curves have been smoothed with a five-point moving average. Error bars indicating plus/minus one standard error have been included for cell types with n ≥ 4. Retinal ganglion cells exhibit a progressive decline in their ability to respond to the depolarizing phase of the stimulus over the course of the trial. This decline is more dramatic for some morphological cell types than for others, and becomes more pronounced as the stimulus frequency is increased.
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pone.0157676.g004: Temporal responses to sinusoidal stimulus currents.(A–C) Probability of observing a spike plotted against time (i.e., cycle count) within each stimulus presentation for stimulus frequencies of 15 Hz, 30 Hz and 60 Hz, respectively. Spike probability curves have been smoothed with a five-point moving average. Error bars indicating plus/minus one standard error have been included for cell types with n ≥ 4. Retinal ganglion cells exhibit a progressive decline in their ability to respond to the depolarizing phase of the stimulus over the course of the trial. This decline is more dramatic for some morphological cell types than for others, and becomes more pronounced as the stimulus frequency is increased.

Mentions: While most cells exhibited either low-pass or band-pass frequency responses, some cells (particularly within the A2 class) exhibited high-pass responses over the range of frequencies tested (see Fig 3A). The 3 dB cut-off frequency for the mean response of each subtype is shown in Fig 3J. The A2i and A2o cell types are most responsive to high frequency stimulation and have the greatest bandwidth, with 3 dB cut-off frequencies of 68 Hz and 56 Hz, respectively. The spiking frequency of these cells plateaued to a rate greater than that of every other cell type for 60 Hz stimuli, responding to ~17% of stimulus cycles at this frequency (Fig 4C). Notably, the C1 and C4o cell types maintain their response to sinusoidal stimulation more reliably than any other cell type within the 15–30 Hz frequency band (Fig 3I; also see Fig 4A and 4B).


Frequency Responses of Rat Retinal Ganglion Cells.

Hadjinicolaou AE, Cloherty SL, Hung YS, Kameneva T, Ibbotson MR - PLoS ONE (2016)

Temporal responses to sinusoidal stimulus currents.(A–C) Probability of observing a spike plotted against time (i.e., cycle count) within each stimulus presentation for stimulus frequencies of 15 Hz, 30 Hz and 60 Hz, respectively. Spike probability curves have been smoothed with a five-point moving average. Error bars indicating plus/minus one standard error have been included for cell types with n ≥ 4. Retinal ganglion cells exhibit a progressive decline in their ability to respond to the depolarizing phase of the stimulus over the course of the trial. This decline is more dramatic for some morphological cell types than for others, and becomes more pronounced as the stimulus frequency is increased.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4920367&req=5

pone.0157676.g004: Temporal responses to sinusoidal stimulus currents.(A–C) Probability of observing a spike plotted against time (i.e., cycle count) within each stimulus presentation for stimulus frequencies of 15 Hz, 30 Hz and 60 Hz, respectively. Spike probability curves have been smoothed with a five-point moving average. Error bars indicating plus/minus one standard error have been included for cell types with n ≥ 4. Retinal ganglion cells exhibit a progressive decline in their ability to respond to the depolarizing phase of the stimulus over the course of the trial. This decline is more dramatic for some morphological cell types than for others, and becomes more pronounced as the stimulus frequency is increased.
Mentions: While most cells exhibited either low-pass or band-pass frequency responses, some cells (particularly within the A2 class) exhibited high-pass responses over the range of frequencies tested (see Fig 3A). The 3 dB cut-off frequency for the mean response of each subtype is shown in Fig 3J. The A2i and A2o cell types are most responsive to high frequency stimulation and have the greatest bandwidth, with 3 dB cut-off frequencies of 68 Hz and 56 Hz, respectively. The spiking frequency of these cells plateaued to a rate greater than that of every other cell type for 60 Hz stimuli, responding to ~17% of stimulus cycles at this frequency (Fig 4C). Notably, the C1 and C4o cell types maintain their response to sinusoidal stimulation more reliably than any other cell type within the 15–30 Hz frequency band (Fig 3I; also see Fig 4A and 4B).

Bottom Line: The least responsive cells were the B2 and C3 types (peaks: 2-5 Hz, cutoffs: 8-11 Hz).We found no difference between cells stratifying in the inner and outer IPL (i.e., ON and OFF cells) or between cells with large and small somas or dendritic fields.Intrinsic physiological properties (input resistance, spike width and sag) had little impact on frequency response at low frequencies, but account for 30-40% of response variability at frequencies >30 Hz.

View Article: PubMed Central - PubMed

Affiliation: National Vision Research Institute, Australian College of Optometry, Carlton, Victoria, Australia.

ABSTRACT
There are 15-20 different types of retinal ganglion cells (RGC) in the mammalian retina, each encoding different aspects of the visual scene. The mechanism by which post-synaptic signals from the retinal network generate spikes is determined by each cell's intrinsic electrical properties. Here we investigate the frequency responses of morphologically identified rat RGCs using intracellular injection of sinusoidal current waveforms, to assess their intrinsic capabilities with minimal contributions from the retinal network. Recorded cells were classified according to their morphological characteristics (A, B, C or D-type) and their stratification (inner (i), outer (o) or bistratified) in the inner plexiform layer (IPL). Most cell types had low- or band-pass frequency responses. A2, C1 and C4o cells were band-pass with peaks of 15-30 Hz and low-pass cutoffs above 56 Hz (A2 cells) and ~42 Hz (C1 and C4o cells). A1 and C2i/o cells were low-pass with peaks of 10-15 Hz (cutoffs 19-25 Hz). Bistratified D1 and D2 cells were also low-pass with peaks of 5-10 Hz (cutoffs ~16 Hz). The least responsive cells were the B2 and C3 types (peaks: 2-5 Hz, cutoffs: 8-11 Hz). We found no difference between cells stratifying in the inner and outer IPL (i.e., ON and OFF cells) or between cells with large and small somas or dendritic fields. Intrinsic physiological properties (input resistance, spike width and sag) had little impact on frequency response at low frequencies, but account for 30-40% of response variability at frequencies >30 Hz.

No MeSH data available.


Related in: MedlinePlus