TTL response accuracy

[duindain]

the keypress version works instantly it must be a problem with the ttl code part

[jarvis24]

That is very odd. Can you send me a sample log data file with say 5-10 trials where you respond consistently--say at around 300ms or so? Maybe once via TTL and once via keyboard? I would like to see what is being saved as the display and RT data for those extra images in the TTL version.