👁 Phase 2 - Encounter
🧠 Formative Quiz
⏱ 2 minutes
Task 3 - Quick Check!
Four short questions about what you just saw in the slides and the Dress Illusion. No grades - just honest thinking. You get instant feedback after each answer.
🏷️ Ungraded - this is for learning, not marks
1
2
3
4
Question 1 of 4
What are the colour-detecting cells in the human eye called?
💡 Remember from Slide 2: the retina contains two types of light-sensitive cells - one for brightness, one for colour.
Correct! Cones are the colour-detecting cells in your retina. You have three types - each sensitive to a different range of wavelengths (roughly red, green, and blue light). Rods detect brightness, especially in the dark, but they do not detect colour.
Not quite. Rods detect light and dark - cones detect colour. There are 3 types of cone cell (S, M and L), each sensitive to a different wavelength. Your brain compares the signals from all three to produce the full range of colour you see.
Question 2 of 4
Which part of your body actually creates the experience of colour?
💡 Think about Slide 3 - the eye sends signals through the optic nerve. But where does the colour experience actually appear?
Correct! The eye collects light and sends electrical signals - but the brain interprets those signals and constructs the colour experience. That is also why the Dress Illusion works: the image is identical, but different brains interpret the lighting differently and produce different colours.
Not quite. The eye collects light and sends signals through the optic nerve - but the brain is what creates the colour experience. Colour is not "in" the eye. It is constructed in the visual cortex. That is why two people can see the same image as different colours.
Question 3 of 4
What does the Dress Illusion show about colour perception?
💡 Think about your vote in Task 2. Why did your classmates disagree with you - were they wrong?
Exactly right! Colour is not only a property of the object. The same image can look completely different depending on surrounding light and how the brain interprets it. Neither person who disagreed about the dress was wrong - their brains made different but perfectly valid assumptions about the lighting.
Not quite. The Dress Illusion shows that colour is not fixed in an object. It depends on how the brain interprets the surrounding light context. Two people looking at an identical image can see completely different colours - not because either is wrong, but because their brains made different assumptions about the ambient light.
Question 4 of 4
Why did different people see the Dress Illusion in different colours?
💡 The image was identical for everyone who saw it. So the difference must come from inside each viewer - not from the image itself.
Brilliant! The image was identical for everyone - the same pixels, the same colours in the file. What differed was how each brain interpreted the context. Brains that assumed warm ambient light saw blue and black. Brains that assumed cooler light saw white and gold. This is colour perception being actively constructed, not passively recorded.
Not quite. The image was absolutely identical for everyone. The difference was entirely inside each viewer: each brain made different assumptions about the ambient lighting conditions in the scene. That caused the very same pixels to be interpreted as completely different colours.
⭐⭐⭐⭐
4
out of 4 correct
🏷️ Ungraded - saved to your portfolio
Your answers
Key takeaway
What happens in Task 3
A 4-question formative pop quiz that follows the Padlet activity in Task 2. Completely ungraded - instant animated feedback is shown after each answer with a minimum 3-second display time. Results go to the teacher dashboard to identify misconceptions before the Investigation phase begins. Students cannot skip any question.
📋 Quiz questions
Q1 · Auto-marked
What are the colour-detecting cells in the human eye called? [Correct: Cones]
Q2 · Auto-marked
Which part of your body actually creates the experience of colour? [Correct: The brain]
Q3 · Auto-marked
What does the Dress Illusion show about colour perception? [Correct: B - depends on lighting context]
Q4 · Auto-marked
Why did different people see the dress in different colours? [Correct: C - brain interpreted lighting differently]
🔑 Key terms
cones
rods
retina
optic nerve
visual cortex
colour perception
Dress Illusion
♿ SEN Adaptations
- Text-to-speech reads every question and all answer options on request (speaker icon)
- Picture-support icons alongside all text answer options (toggle in accessibility settings)
- Extended time: 1.5× or 2× available per student, set by teacher in dashboard before quiz starts
- All feedback text uses plain language - no jargon without explanation
- Ungraded badge clearly displayed so students know this does not affect their score
🖨️ No-Tech Format
- Teacher reads all 4 questions aloud - students hold up A/B/C/D response cards
- Teacher gives verbal feedback after each question using the same hint text from the screen
- Students record their answers on a printed quiz sheet
- Results reviewed verbally with the class before moving to Phase 3
📊 Teacher Dashboard
- Results saved per student with timestamp immediately after each answer
- Class summary shows % correct per question - highlights misconceptions before Phase 3
- Score visible to teacher only - students see ungraded badge only
- CSV export available after lesson ends