Identifying Cell Class Specific Losses from Serially Generated Electroretinogram Components
Figure 4
Previous approaches to determine “downstream effects”: ratio analysis ((a) and (b)) and percentage change relative to a normal cohort ((c) and (d)) of ω-3 dietary deficiency. Panels (c) and (d) are reproduced with permission from Nguyen et al. [28]. Asterisks (*) indicate a statistically significant direct loss at the respective cell (P < 0.05). (a) Ratio analysis of amplitudes indicates no dietary change (ω-3+ white bars, ω-3− black bars) in the nor ratio but a significant decrease in the ratio. (b) Ratio analysis of implicit times indicates an increase in the ratio and a decrease in the pSTRit/PIIit ratio and ratio. (c) Percentage change analysis relative to the average control value (±95% CI, grey shaded area) indicates that ω-3 deficiency (average ± SEM, filled circle) exhibits greater dysfunction in the pSTR than the PIII, PII, or nSTR (d) Percentage analysis also indicates a greater delay in timing in the PII than the PIII, pSTR, or nSTR. Thus when comparing the ratio and percentage change analysis with the gain analysis (Figure 3) differences can be noted. Ratio and percentage change analyses indicate that all inner retinal timing changes are direct effects (PIIit, pSTRit, and nSTRit), whereas by taking into account gain between ERG components the timing delays of inner retinal components are attributable to the initial photoreceptoral change. Coincidentally, the amplitude changes are in agreement between the 3 analyses techniques.
