Simon and Chabris (1999): Inattentional blindness

Question 1

Background of study

Answer 1

Previous studies showed interest in visual representation; in these studies observers would engage in a task which required them to focus on a visual scene whilst ignoring others. At one point an unexpected event would happen. Results showed the majority of observers didn’t report seeing the UEE.

-Previous research didn’t consider the difficulty in detection and no comparisons were made.

Question 2

Research method

inc IV and DV

Answer 2

Lab experiment using IMD
Ivs: Transparent/Opaque, Umbrella woman/Gorilla, Balck/White, Easy/Hard

DV: Number of ps saw the UEE

• There were 16 conditions
• A controlled observation was conducted in which ps watched a different video (easy/white task)

Question 3

MAterials used ins study

Answer 3

• 4 video tapes, each 75 -secs each
• Each tape showed 2 teams of 3 , 1 team wearing white shirts, the other wearing black
• Players moved around in random way in front of lift doors
• Players passed in this order: 1-2-3-1
• After 44-48 secs the UEE would happen:Either a woman holding an umbrella or a woman dressed up as a gorilla
• There was a transparent and opaque style of video.
• Filmed on a SVHS video camera

Question 4

Sample

Answer 4

228 ps= all undergrads

• Each p volunteered or paid a single fee for taking part in a larger testing session
• Data from 36 ps were discarded, using results from only 192 ps

For controlled observation: 12 different ps watched a video, in which a gorilla thumped his chest

Question 5

Procedure

Answer 5

• 21 experimenters tested the ps. To ensure standardised procedure they made a written protocol.
• All ps tested individually and gave informed consent
• They were told to either pay attention to the team in white (white condition) or black (black condition)
• Told to either keep a mental count o the number of passes (easy) or the number of bounces and ariel passes (hard)
• After watching video ps were asked questions as to whether they saw anything unusual. If ‘yes’ they would give details on what they saw
• Ps were debriefed
• Each testing sesh lasted 5-10 mins

Question 6

Key findings

Answer 6

• Out of all 192 ps across all conditions only, 54% noticed the UEE and 46% failed to notice it.
• More ps noticed the UEE in the opaque con (67%) than in transparent con (42%)
• 33% of those in OC failed to report the event, despite its visability and repeated questions about it.
• More people noticed it in easy (64%) than hard (45%) con
• Difficulty greater in TC (Easy 56% Hard 27% per condition) than in OC (E 71% H 62% per condition)
• UW (65%) noticed more than G(44%) overall
• G noticed more in black team (58%) than white (27%)

Controlled Obs: Only 50% noticed the UEE

Question 7

Conclusions

Answer 7

• Individuals have sustained inattentional blindness
• Individuals fail to notice an event if engaged in a primary task
• Level of inattentional blindness depends on the difficulty of primary task
• Individuals more likely to notice UEE, if similar to primary event
• There is no conscious perception without attention