- Latencies decrease with age in the nonlagged population. This trend is not evident in the entire population because immature nonlagged cells overlap in latency with lagged cells.
- Lagged cells develop stronger inhibition late in postnatal development, giving them their characteristic absolute phase lag.
- ON/OFF cells may exist in the A-layers of kittens. It is often difficult to tell whether cells are lagged ON (OFF) or nonlagged OFF (ON) as well.
- Despite the difficulties in classifying cells, some neurons are clearly lagged or nonlagged even in 5 week old kittens. Relatively mature cells exist early in development, but are much less common.
- Predictions from these data are that cortical direction selectivity:
- is less prominent at low temporal frequencies in young kittens, because the variance in absolute phase is so low; and
- is ubiquitous at higher temporal frequencies, because of the huge variance in latencies in these kittens.
Back to index
Date created: November 5, 1997
Last modified: November 5, 1997
Copyright © 1997, Alan Saul
Maintained by: Alan Saul