Simons & Chabris

Question 1

What is the meaning of change blindness?

Answer 1

• situation where observers often fail to notice large changes to objects, particularly in objects that aren’t the centre of interest

Question 2

What is the meaning of inattentional blindness?

Answer 2

• situation where observers fail to perceive unexpected objects when attention is diverted to another object/task. happens even if the object appears in the centre of the display.

Question 3

What is the background?

Answer 3

• static visual displays -> Mack and Rock (static cross study)
• dynamic visual displays -> Neisser (The Umbrella Woman)

Question 4

What were the aims?

Answer 4

• to build on previous research and investigate the factors that may affect visual detection rates

Question 5

What were the factors that may affect visual detection rates?

Answer 5

1. the visual similarity of the unexpected object and attended ones
2. task difficulty
3. superimposed version of the display versus a live version
4. the nature of the unusual event

Question 6

What were the research methods?

Answer 6

• lab experiment, independent measures design

Question 7

What were the IV’s?

Answer 7

• unexpected event (umbrella woman/gorilla)
• film (transparent/opaque)
• participant followed (black team/white team)
• task (easy/hard)

Question 8

What was the DV?

Answer 8

• number of participants who noticed the umbrella woman/gorilla

Question 9

What was the sample of the study?

Answer 9

• 228 undergrad students, USA, self-selected, rewarded through a candy bar
• final analysis -> 192 (36 were ruled out because they already knew about the video)

Question 10

What was the sample of the control group?

Answer 10

• 12 participants in a controlled observation

Question 11

What materials were used?

Answer 11

• 4x video tapes of 2 teams (3 players each) throwing basketballs
• each tape lasted 75 seconds
• after 44-48 seconds, unexpected event occurred (lasting 5 seconds)
• unexpected person walked from the left to the right
• transparent video (superimposed), opaque video (all filmed at the same time)

Question 12

What was the procedure?

Answer 12

• participants tested individually, told to keep a silent mental count of:
  -> total number of passes (easy)
  -> total number of bounce/aerial passes (hard)
• immediately after, were asked to write down their counts
• surprise series of questions (‘did you notice anything unusual’)
• if ppts said yes, they were asked for details
• observers gave informed consent and were debriefed at the end by replaying the video

Question 13

What were some results?

Answer 13

• 54% of observers did notice the unexpected event
• umbrella woman was noticed more
• no correlation between noticing and poor counting

Question 14

What were some conclusions?

Answer 14

• results shown sustained inattentional blindness for dynamic events
• factors that lead to inattentional blindness:
  -> transparent display
  -> difficulty of primary task
  -> less likely to notice events if event is dissimilar to the event they are paying attention to
  -> there is no conscious perception without attention