A version of the talk I originally gave to the Auckland Web Meetup - where I show a couple of strange perceptual phenomena that may explain the lack of usability in some websites.

1. ti ne
J us
ac ti
s e rf
U
on

2. Users are dumbl
b in
d

3. a n d in c r e d ib ly
w ha t w e do n’ t s e e
bus y

4. Inattentional blindness

5. change blindness

12. spot the error message

17. b e fo re a fte r o r n e x t
to

18. w ha t w e do s e e
http://flickr.com/photos/naoh

19. Pre-attentive processing

20. Colour is pre-attentive

21. Shape is pre-attentive

22. Where’s the red circle now?

28. Preattentive Processing

30. www.lisarienermann.com
t h e w h o le is m o r e t h a n
t h e s u m o f it s p a r t s

31. Which way to the toilets?
Thisisbroken.com

32. gestalt principles

33. .
From moonbird's Flickr stream

34. page elements create lines &
shapes

39. http://flickr.com/photos/morgantepsic
s o c o m m o n it
b e c o m e s in v is ib le

40. alerts

41. what the user sees

42. to s u m u p …