The human focal electroretinogram as a function of stimulus area

Pierangelo Errico, Benedetto Falsini, Vittorio Porciatti, Francesco Maria CefalÁ

Research output: Contribution to journalArticlepeer-review

7 Scopus citations


Focal electroretinograms to on-off luminance modulation (2.7 Hz) of uniform fields with a different area (144-2.25 deg2) centered on the fovea were recorded in two young normal subjects. The electroretinogram responses typically consisted of an a-wave, a b-wave, a PIII component and a d-wave. The concentric reduction of the test field size caused progressive amplitude decrement of all components, while their response density increased. The spatial summation properties of the b-wave differed from those of the a-wave, PIII component and d-wave so that the relative contribution of the b-wave to the electroretinogram waveform depended on the stimulus area. For a critically small field size, the electroretinogram was dominated by the PIII and d-wave components. Only these two electroretinogram components displayed a density profile that could be compared with that of cone distribution.

Original languageEnglish (US)
Pages (from-to)41-48
Number of pages8
JournalDocumenta Ophthalmologica
Issue number1
StatePublished - Aug 1990
Externally publishedYes


  • b-wave
  • d-wave
  • electroretinogram components
  • PIII component
  • spatial summation

ASJC Scopus subject areas

  • Ophthalmology

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