Welcome to Cognitive Psychology!

Ever been so focused on a text message that you walked right into a lamp post? Or perhaps you've been looking for your keys only to realize they were in your hand the whole time? This chapter is all about inattentional blindness—the surprising way our brains can "miss" something right in front of our eyes when we are busy focusing on something else.

In the OCR A Level curriculum, this study by Simons and Chabris (1999) is the contemporary study for the Cognitive Area, specifically under the key theme of Attention. It builds on the work of Moray (1959), who looked at auditory (hearing) attention, by exploring how we process visual information.

The "Big Idea": Background

Before this study, researchers like Neisser had shown that people could miss unexpected events when watching overlapping videos (a technique called "selective looking"). Simons and Chabris wanted to see if this happened in more "real-life" looking scenarios and what factors made us more or less likely to notice an unexpected visitor—like a person in a gorilla suit!

Key Term: Inattentional Blindness

This is the failure to notice a fully visible, but unexpected, object because your attention is focused on another task, event, or object.

The "Story" of the Study: Method

The Participants (The Sample)

The researchers recruited \( 228 \) "observers" (mostly undergraduate students). Some were volunteers, while others received a small payment or a chocolate bar. However, data from only \( 192 \) participants were used in the final results to ensure all conditions had an equal number of people.

The Design

This was a Laboratory Experiment using an Independent Measures Design. This means each participant only took part in one of the many conditions.

There were four Independent Variables (IVs) that created \( 16 \) different conditions in total:

  1. The Unexpected Event: Did a tall woman with an umbrella walk across the screen, or a shorter person in a gorilla suit?
  2. The Film Type: Was the video Transparent (the two teams were superimposed over each other so you could see through them) or Opaque (a normal-looking video)?
  3. Task Difficulty: Was it Easy (counting the total number of passes) or Hard (keeping separate mental counts of "bounce" passes and "aerial" passes)?
  4. Attended Team: Was the participant told to follow the team wearing White shirts or the team wearing Black shirts?
The Procedure

1. Participants watched a \( 75 \)-second video of two teams of three players passing a basketball.
2. After about \( 44 \)–\( 48 \) seconds, the "unexpected event" (Umbrella Woman or Gorilla) walked across the screen for \( 5 \) seconds.
3. Participants were asked to write down their count of passes immediately.
4. Then came the "surprise" questions: "Did you notice anything unusual?" or "Did you see anyone other than the six players?"
5. If they said "yes," they had to describe what they saw. They were also asked if they had ever seen a study like this before (if they had, their data was discarded to avoid demand characteristics).

What Did They Find? (Results)

The results were quite shocking to many people! Overall, only \( 54\% \) of participants noticed the unexpected event. This means \( 46\% \) failed to see a gorilla or an umbrella woman walking right through the game!

Key Findings:

  • Opaque vs. Transparent: Participants were much more likely to notice the event in the Opaque (normal) video (\( 67\% \)) than in the Transparent video (\( 42\% \)).
  • Easy vs. Hard Task: More people noticed the event during the Easy task (\( 64\% \)) than the Hard task (\( 45\% \)). This shows that as the primary task gets harder, we have less "mental energy" left to spot unexpected things.
  • Similarity Effect: Participants following the Black team were more likely to notice the Gorilla (who was also black) than those following the White team. This suggests we are more likely to notice unexpected objects if they look like what we are already looking for.
  • The Umbrella Woman: She was noticed more often than the Gorilla overall (\( 65\% \) vs \( 44\% \)).

Quick Review Box:
If you are working really hard on a difficult task (Hard Task) and something happens that doesn't look like what you're focusing on (e.g., following the White team but a Black Gorilla appears), you are very likely to miss it!

Conclusions

Simons and Chabris concluded that:

  • Inattentional blindness occurs for dynamic (moving) events.
  • The level of inattentional blindness depends on the difficulty of the task.
  • We are more likely to notice unexpected objects if they are visually similar to the objects we are attending to.
  • There is no conscious perception without attention—just because something enters our field of vision doesn't mean we "see" it.

Linking to Themes and Areas

The Cognitive Area

This study belongs to the Cognitive Area because it investigates the internal mental process of attention. It demonstrates how our brain filters information and that our perception of the world is not a perfect recording, but a selective process.

Key Theme: Attention

This study changes our understanding of attention by showing that it is multimodal. While Moray (1959) showed we filter out sounds in a busy room (auditory attention), Simons and Chabris show we do the exact same thing with sight (visual attention).

Contemporary vs. Classic Study
  • Similarities: Both Moray and Simons & Chabris were highly controlled laboratory experiments. Both showed that we can "block out" significant information when we are focused.
  • Differences: Moray used auditory stimuli, while Simons & Chabris used visual stimuli. Simons & Chabris also looked at how the nature of the task (difficulty/similarity) affected attention, whereas Moray focused on specific cues (like hearing your own name).

Evaluating the Study (AO3)

Strengths:

  • High Internal Validity: The use of a standardized video and specific instructions meant the researchers could be sure that the IV (e.g., task difficulty) was affecting the DV (noticing the gorilla).
  • Large Sample: With \( 192 \) participants, the results are more likely to be representative and reliable.
  • Practical Applications: This research is very useful. It helps explain why pilots might miss another plane on the runway if they are focused on their controls, or why drivers might miss a cyclist if they are looking for cars.

Weaknesses:

  • Low Ecological Validity: Watching a video of people passing a ball in a lab isn't exactly like real life. In reality, unexpected events are often accompanied by noise or other sensory information.
  • Sampling Bias: Using students might be a problem as they are often young and might have better cognitive/attentional skills than the general population.

Common Mistake to Avoid:
Don't confuse "Inattentional Blindness" with "Change Blindness." Inattentional blindness is missing something that is there because you are focused elsewhere. Change blindness is failing to notice a difference between two scenes (like a person changing their shirt).

Key Takeaway:
Our brains have a limited capacity for attention. When we "pay" attention to one thing, we might be going "bankrupt" for everything else happening around us!