Simons and Chabris Flashcards
Aim?
To investigate the influence of several factors on inattentional blindness. One of these was looking at the effect of superimposition compared to live events within the video recording, another was measuring the impact of task difficulty and a third considered whether the unusualness of the unexpected event had an impact on detection rates
Research method?
Lab experiment
Experimental design?
Independent measures
How many conditions were there?
16 conditions-
4 conditions of the unexpected event and 4 possible combinations of easy/hard and white team/black team
Sample?
228 participants recruited using volunteer sampling. Most were undergraduate students who were offered a reward of a candy bar or a single fee for their participation in this and other unrelated studies
Procedure?
The researchers created 4 videotapes using the same camera, each lasting 75 seconds. Each tape showed 2 teams of 3 players, one team wearing white shirts and the other wearing black shirts. The members of each team moved randomly around a small space, passing an orange basketball to one another in a set order, either as an aerial pass or a pass with a bounce. 21 experimenters tested the participants individually. They used a standardised script to deliver instructions on the task and carefully followed a written protocol outlining how and when to present the video and collect data each trial. The videos were presented on a variety of television monitors ranging in size between 13-36 inches. After performing the task, observers were immediately asked to write down their count of passes then verbally answered a surprise set of questions. Details of any ‘yes’ responses were noted. Observers were then asked whether they had previously heard of/participated in an experiment like this before. Lastly, they were debriefed and given the opportunity to re-watch the video
IV’S?
One IV was the two 5 second unexpected events, which appeared after 44-48 seconds into the videos. In one condition, known as the ‘Umbrella Woman’ condition, a tall woman holding an open umbrella walked across the picture from left to right. In the ‘Gorilla’ condition a shorter woman wearing a full gorilla costume walked through the action in the same way
The 2nd IV was the 2 styles of video; in the ‘Transparent’ condition, each of the teams and the unexpected event were all filmed separately, made partially transparent then superimposed on one another using digital techniques. In the ‘Opaque’ condition, all 7 actors were filmed at the same time which required careful rehearsal to avoid collision
The 3rd IV was the team colour that the participants were asked to follow (black or white). Participants were instructed to keep either a silent mental count (easy condition) or seperate mental counts of the number of bounce passes and aerial passes made by theteam (hard condition)
The 4th IV was the difficulty of the task (easy or hard)
Surprise set of questions?
1) While you were doing the counting, did you notice anything unusual on the video?
2) Did you notice anything other than 6 players?
3) Did you see anyone else appear on the video?
4) Did you see a gorilla/woman with umbrella walk across the screen
Results?
For a number of reasons, some participant data had to be discarded because ppts admitted to having heard of inattentional blindness, or that they had lost count of the number of passes. The remaining 192 ppts were distributed equally across the 16 conditions of the 2x2x2x2 design (12 per condition)
Out of the 192 participants across all conditions, 54% noticed the unexpected event and 46% failed to notice the unexpected event. This key finding supports existing research findings, with participants demonstrating a substantial level of inattentional blindess for a dynamic avent.
Participants were more likely to notice the unexpected event in the opaque condition (67%) compared to the transparent condition (42%) however this still leaves a significant proportion of ppts in the opaque condition who failed to detect the event.
As expected, more participants noticed the unexpected event in the easy condition (64%) than the hard (45%)
More participants noticed the umbrella woman (65%) than the gorilla (44%)
When participants were attending to the black team were more likely to notice the gorilla (58%) than when attending to the white team (27%) but there was little different in noticing the women between the black team (62%) and the white team (69%)
Instead of the gorilla being noticed by standing out against the white team, ppts were more likely to notice an event that shares basic features with the object they are observing (same colours)
Research method evaluation?
Controls- timings of presentations were identical for each participant and the moves in ‘opaque’ condition were carefully rehearsed so that the videos for the black and white teams were the same
Data evaluation?
Quantitative data in the form of ‘yes/no’ responses following the video- easy to analyse and not open to interpretation and allowed for comparison between conditions
Ethical considerations
Consent was obtained
Although design required that ppts were not fully aware of the true aim, the video and questioning were unlikely to cause distress and they were fully debriefed and allowed to watch the video again- this is important as finding out there had been a gorilla/umbrella woman they had not seen might have been frustrating
Validity?
Low ecological validity because completed task watching a video not in real life. In real life even when we concentrate carefully on tasks requiring our attention there would be a number of other environmental distractions furthermore the task of counting ball passes does not fully reflect our typical visual attention tasks
This findings were consistent with previous research, including computerised trails of inattentional blindness, increasing the likelihood that we can generalise the findings to other situations however roughly only half noticed the unexpected event so inattentional blindness is not a universal visual experience
Reliability?
A large number of researchers were conducting the individual trials which needed a range of television screen sizes (13-36 inches) which could have introduced inconsistencies which could raise reliability issues however this was controlled through the use of a standardised script
Sampling bias?
May be difficult to generalise as was mainly undergraduate students as they are likely to be more vigilant than average as they are young people
However the researchers controlled for participant variables such as knowledge of the phenomenon being investigated which would remove bias
