The concept of induced components in multifocal electroretinograms

PURPOSE: In the late period of a multifocal electroretinogram (mfERG) waveform, higher order-kernels copy themselves. These images are called projection components(or induced components), and contribute to the particular waveform of mfERG. I describe this feature, which the developer of the multifocal technique was fully aware of. METHOD: Inter-kernel comparisons were made of mfERGs, focusing on the characteristics and influence of induced components. RESULTS AND DISCUSSION: Even though induced components have never been described or discussed in detail in Japan, they are certainly one of the key elements in learning how the multifocal technique works and what the difference is between multifocal and conventional ERGs.