Can focusing our attention make us completely miss an obvious, unexpected event right in front of us?
Contemporary study: Simons and Chabris (1999), Gorillas in our midst: sustained inattentional blindness. Aim, method, results and conclusions, evaluation, and links to the cognitive area and Moray.
An OCR A-Level Psychology answer to the contemporary cognitive study, Simons and Chabris (1999) on sustained inattentional blindness (the invisible gorilla). Covers the aim, the basketball-counting method, the gorilla and umbrella-woman conditions, the noticing rates, evaluation, and links to Moray and the cognitive area.
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What this dot point is asking
Simons and Chabris (1999) is the contemporary study in the cognitive area for the theme "attention", paired with Moray. You must know its aim, method, results and conclusions, evaluate it, and explain what it adds to the cognitive area and how it compares with Moray.
The answer
Aim and method
The design manipulated four things: the unexpected event (an umbrella woman or a gorilla); the video as transparent (superimposed) or opaque (one continuous scene); and the counting task as easy or hard. The unexpected event walked through the scene for about 5 seconds.
Results and conclusions
Evaluation
- Control and reliability. A highly standardised procedure (the same videos, instructions and timing) gives strong internal validity and replicability.
- Sample. Large (228), improving generalisability, with a real, striking effect.
- Ecological validity. Low: counting basketball passes is an artificial demand and the video task has no real consequences, unlike everyday attention.
- Demand characteristics. Participants who guessed the aim were excluded, but some demand effects may remain.
- Application. Real-world value: it helps explain why eyewitnesses, drivers or radiologists can miss the unexpected when concentrating.
Examples in context
Example 1. Why this study defines the cognitive area. The cognitive area treats perception as active processing rather than passive recording. Simons and Chabris show that what reaches conscious awareness is shaped by where attention is directed, so half of viewers can miss a person in a gorilla suit. This demonstration of selective attention shaping perception is squarely a cognitive-area finding.
Example 2. The contrast with Moray. Moray studied auditory attention (how much of an unattended message we process), finding most is filtered out but salient information can break through. Simons and Chabris study visual attention, showing focused attention can make an obvious event invisible. Together they reveal selective attention across senses, the classic-contemporary comparison the exam asks for in the cognitive area.
Try this
Q1. State the percentage of participants who failed to notice the unexpected event. [1 mark]
- Cue. About 46 per cent overall.
Q2. Explain what is meant by sustained inattentional blindness. [2 marks]
- Cue. Failing to consciously perceive an obvious, unexpected object that is in full view because attention is focused on a demanding task.
Q3. Explain one real-world implication of Simons and Chabris's findings. [3 marks]
- Cue. People concentrating on a task (such as drivers, eyewitnesses or radiologists) may miss an obvious unexpected event (a hazard, an incident, an abnormality), because focused attention reduces the capacity to perceive the unexpected.
Exam-style practice questions
Practice questions written in the style of OCR exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
OCR 202010 marksDescribe the method and results of Simons and Chabris's (1999) study of inattentional blindness. [10 marks]Show worked answer →
A description item testing method and results (AO1).
Method: a laboratory experiment in which 228 participants watched a short video of two teams (one in white, one in black) passing basketballs. Participants counted the passes made by one team. Conditions varied four things: the unexpected event (a woman with an umbrella, or a person in a gorilla suit), whether the video was "transparent" (superimposed images) or "opaque" (one continuous scene), and whether the counting task was easy (count total passes) or hard (count bounce and aerial passes separately). About 5 seconds into the video the unexpected event walked through the scene for about 5 seconds.
Results: overall, about per cent of participants failed to notice the unexpected event (inattentional blindness). The gorilla was noticed less than the umbrella woman, the opaque condition produced more noticing than the transparent condition, and the harder counting task reduced noticing.
Markers reward the basketball-counting task, the gorilla and umbrella-woman events, the opaque/transparent and easy/hard manipulations, and the key result that about 46 per cent missed the unexpected event.
OCR 202212 marksDiscuss what Simons and Chabris's (1999) study tells us about attention, including its strengths and weaknesses. [12 marks]Show worked answer →
Tests interpretation plus evaluation (AO1 and AO3).
What it tells us: when attention is focused on a demanding task, people can fail to consciously perceive an obvious, unexpected object in plain view (sustained inattentional blindness). This shows perception is not a simple recording of the visual field but depends on where attention is directed, and that the harder the attended task, the more is missed.
Strengths: high control and standardisation (the same videos, instructions and timing) give strong internal validity and replicability; a large sample (228) improves generalisability; and clear quantitative data on noticing rates.
Weaknesses: the lab video task is artificial and unlike real-world attention (where consequences matter), limiting ecological validity, and counting passes is an unusual demand; participants who guessed the aim were excluded, but demand characteristics remain possible.
A strong answer concludes that the study robustly demonstrates inattentional blindness with real implications (for example, eyewitnesses or drivers missing the unexpected), while its artificiality limits how far the exact rates generalise. Markers reward interpretation plus balanced evaluation.
Related dot points
- Classic study: Moray (1959), Attention in dichotic listening. Aim, method, results and conclusions, evaluation, and links to the cognitive area and theories of attention.
An OCR A-Level Psychology answer to the classic cognitive study, Moray (1959) on attention in dichotic listening. Covers the aim, the three dichotic-listening experiments, the shadowing and own-name findings, the link to Broadbent's filter model, evaluation, and links to Simons and Chabris and the cognitive area.
- Classic study: Loftus and Palmer (1974), Reconstruction of automobile destruction. Aim, method, results and conclusions, evaluation, and links to the cognitive area and eyewitness memory.
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- Contemporary study: Grant et al. (1998), Context-dependent memory in the learning and retrieval of meaningful material. Aim, method, results and conclusions, evaluation, and links to the cognitive area and Loftus and Palmer.
An OCR A-Level Psychology answer to the contemporary cognitive study, Grant et al. (1998) on context-dependent memory. Covers the aim, laboratory-experiment method with matching and mismatching noise conditions, the context-dependency findings, evaluation, real-world application, and links to Loftus and Palmer and the cognitive area.
- Research methods and techniques: experiments, self-report, observation and correlation; variables and operationalisation; experimental designs; hypotheses; and the strengths and weaknesses of each method.
An OCR A-Level Psychology answer to research methods and design, covering laboratory, field and quasi-experiments, self-report, observation and correlation, independent and dependent variables, operationalisation, experimental designs, directional and non-directional hypotheses, and the strengths and weaknesses of each technique for Component 1.
- Sampling methods, ethical considerations, reliability and validity, levels of measurement, and recording, analysing and presenting data.
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Sources & how we know this
- OCR Level 3 Advanced GCE in Psychology (H567) specification — OCR (2015)