Anyone watching Horizon on BBC4 looking at human perception? Here's a good one.They just showed a clip of 6 guys playing basketball, 3 in yellow, 3 in blue, and we're asked to count the number of times the guys in yellow pass the ball. Ok, thought, this should be easy. I counted 13 passes. At the end of the clip the guy says 'did anyone notice anything strange there?' So we were then invited to watch the clip as you would normally.And a bloke in a gorilla suit walked through the middle of the basketball game, stopped, stood bang centre in the middle of the picture and waved.I didn't see it when I was counting the passes. Absolutely stunning that you can miss something as obvious as that.You want the answer to why SMIDSY's happen, it's visual perception problems .. ..