Temporal-frequency tuning of direction selectivity in cat visual cortex

Alan B. Saul, Allen L. Humphrey

Research output: Contribution to journalArticlepeer-review

79 Scopus citations


Responses of 71 cells in areas 17 and 18 of the cat visual cortex were recorded extracellularly while stimulating with gratings drifting in each direction across the receptive field at a series of temporal frequencies. Direction selectivity was most prominent at temporal frequencies of 1–2 Hz. In about 20% of the total population, the response in the nonpreferred direction increased at temporal frequencies of around 4 Hz and direction selectivity was diminished or lost. In a few cells the preferred direction reversed. One consequence of this behavior was a tendency for the preferred direction to have lower optimal temporal frequencies than the nonpreferred direction. Across the population, the preferred direction was tuned almost an octave lower. In spite of this, temporal resolution was similar in the two directions. It appeared that responses in the nonpreferred direction were suppressed at low frequencies, then recovered at higher frequencies. This phenomenon might reflect the convergence in visual cortex of lagged and nonlagged inputs from the lateral geniculate nucleus. These afferents fire about a quarter-cycle apart (i.e. are in temporal quadrature) at low temporal frequencies, but their phase difference increases to a half-cycle by about 4 Hz. Such timing differences could underlie the prevalence of direction-selective cortical responses at 1 and 2 Hz and the loss of direction selectivity in many cells by 4 or 8 Hz.

Original languageEnglish (US)
Pages (from-to)365-372
Number of pages8
JournalVisual Neuroscience
Issue number4
StatePublished - Apr 1992
Externally publishedYes


  • Direction selectivity
  • Lagged cells
  • Lateral geniculate nucleus
  • Temporal frequency
  • Visual cortex

ASJC Scopus subject areas

  • Physiology
  • Sensory Systems


Dive into the research topics of 'Temporal-frequency tuning of direction selectivity in cat visual cortex'. Together they form a unique fingerprint.

Cite this