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selective attention test

Daniel Simons
Demos
YouTube
3 HN users recommended this demo3 months2011–2025 score 3.5
Years with an HN recommendation, 2007–2026

HN uses it constantly as the classic demonstration that attention is selective, in threads on driving, motorcycles, AI and perception.

The original invisible gorilla awareness test by Daniel Simons and Christopher Chabris, in which viewers count basketball passes and often miss a gorilla crossing the scene. It demonstrates inattentional blindness.

“a longer but more relevant "motorcycle invisibility training" video” (HN, 2019)

1 strong recommendations · 2 recommendations · 16 citations · 1 jokes · Demos

20 Hacker News comments

From the HN archive; up to 20 kept per video, favoring different commenters. Recommendations first.

@chrisweekly Oct 2019 Strongly recommends
on HN thread Lethal memory fail: Why drivers see, and then forget motorcyclists
As a motorcyclist -- and lifelong learner w/ a degree in cognitive psychology -- I really appreciate demonstrations like this one^1 from Daniel Simons. It's a short video (< 90s), but for many first-time viewers, it's an eye-opening experience. ^1. [this video] Edit: just saw @elosarv's link to a longer but more relevant "motorcycle invisibility training" video ( [link]
Short demonstration that is eye-opening for first-time viewers
@crispyambulance Sep 2018 Recommends
on HN thread A Fighter Pilot’s Guide to Surviving on the Roads
Read more
This is sound advice. The only time I've made contact with a moving car as a cyclist was when I was going past an off-ramp. The weird thing was that I thought the driver "saw me". It was late morning, no problem with visibility. From my POV, she was looking right at me. In fact, she was looking "through" me. She simply was expecting other cars and a person on a bike was not what she was looking for. Human attention is very much selective. Check out this shocking video: [this video] After that, I ride with a bright flashing headlight at all times, even daylight. It gives some measure of protection, I think.
Demonstrates selective attention relevant to drivers missing cyclists
@meowster Aug 2024 Recommends
on HN thread Massachusetts 'Reviewing' Kei Car Ban After Uproar over Canceled Registrations
It's called Selective Attention which explained in another comment: > Notably, people tend to see what they expect to see. > When they are looking for cars, they tend not to see motorcycles, even when they are in plain view. Watch/take this Selective Attention test (1 min 22 sec): [this video]
Short test showing people see what they expect

Citations, criticism and jokes

@brisance Mar 2011 Cites it
on HN thread Multitasking
However, the argument that multitasking on computers is bad because humans can’t multitask is flawed. That was right in the article itself. I believe the author's point is that focus/attention is more important than being able to "multi-task". Refer to Daniel Simons's experiment (the invisible gorilla) on selective attention. [this video]
Selective attention experiment supporting focus over multitasking
@Someone Mar 2014 Cites it
on HN thread Gunshot victims to be suspended between life and death
I am not sure we even know that normal consciousness is continuous. We experience it that way, but that says nothing. We think our vision is continuous, too, but it isn't ( [this video] . More info at [link] (had to use a shortener because the URL gives information away for those who don't know this experiment))
Shows vision is not as continuous as it feels
@cooper12 Jan 2016 Cites it
on HN thread A Canvas Made of Pixels
Your video reminded me of this selective attention test: [this video] . This Wikipedia article also seems to be related to the phenomenon and talks about the video too: [link] .
Selective attention test related to discussion
@JadeNB May 2017 Cites it
on HN thread At The Dawn Of Recorded Sound, No One Cared
Read more
> The notion of not knowing why recording sound could be useful to me is hard to grasp as someone who has always been around it. This seems like (from their point of view) the Blub paradox ( [link] ), and (from our point of view) something of its converse. From their point of view, they couldn't see the importance of sound recording because they didn't have any existing mechanisms to make use of it. From our point of view, we can't not see the importance of sound recording, because we have so many ways of making use of it. (Kind of like how, once you know the effect being demonstrated in [this video] , you not only no longer experience it, but find it hard to believe that you ever did.)
Analogy: once you know the effect you cannot unsee it
@tmh88j Feb 2020 Cites it
on HN thread Tesla's self driving algorithm's overlay [video]
> You see a handful of lines and text across the screen and it's sufficient to make you go ":o"? Enough to conclude it must be better than a brain? I think he's referring to selective attention. Can't comment on the validity of this "study", but I recall it catching me off guard the first time I saw it. [this video]
Selective attention can catch viewers off guard
@jfim Feb 2020 Cites it
on HN thread Tesla's self driving algorithm's overlay [video]
Oh definitely. The selective attention test [0] really shows how humans can perceive certain things in a way that's different from how computers perceive them. The research on GANs also shows how computers can be fooled by things that wouldn't confuse humans. [0] [this video]
Shows humans perceive differently from computers
@aaron695 Mar 2021 Cites it
on HN thread Drivers new to level 2 driving assistance had lower awareness of on-road events
The moonwalking bear/gorilla comes to mind for this. Gorillas in our midst: sustained inattentional blindness for dynamic events - [this video] / [link] But I'm not sure what that means, is it good or bad to see the bear. You are driving not looking at pretty things. You want to reduce dimensions. It's a 1 tonne vehicle, color shouldn't matter.
Inattentional blindness study related to driver awareness
@sankyo Jun 2023 Cites it
on HN thread Invisibility Training for Motorcyclists [video]
This old psychology video comes to mind. [this video] Also, in San Francisco a lot of the "paint" in the crosswalks is little plastic pellets melted. I have had my rear wheel slide out going over the thick white crosswalk bars. Best to keep off the throttle and roll over them. Same for the giant metal plates they use to cover up ongoing construction projects. They can be very slippery.
Classic psychology video relevant to motorcycle invisibility
@BoppreH Dec 2023 Cites it
on HN thread Three Things That LLMs Have Made Us Rethink
Read more
> it doesn't understand its own limitations, ie it has no self awareness. And how much self awareness do humans have, exactly? We walk around with heads filled with false memories[1], accidentally ignore surprisingly prominent stimuli[2], and struggle to understand things as simple as material color[3]. And people are mostly unaware of these limitations, or those examples would not be considered surprising! I think we plan around the limitations we observe, not our real limitations. If that's the case, then LLMs simply lack training data to notice those limitations. [1] [link] [2] [this video] (old selective attention test) [3] [link]
Example of humans ignoring prominent stimuli
@Retr0id Mar 2024 Cites it
on HN thread Chess puzzle, but you are what you capture
Yup, you can't move to them. Weirdly I didn't notice them at all until several attempts in (and was getting confused as to why certain moves weren't allowed), in a way that reminded me of the Selective Attention Test[0]. Once I'd clocked them I was able to solve it pretty quickly. [0] [this video]
Analogy for missing obstacles in a puzzle
@jetrink Oct 2024 Cites it
on HN thread Meta Movie Gen
Read more
A friend who lives in North Carolina sent me a video of the raging floodwaters in his state- at least that's what the superimposed text claimed it was. When I looked closer, it was clearly an Indian city filled with Indian people and Indian cars. He hadn't noticed anything except the flood water. It reminded me of that famous selective attention test video[1]. I won't ruin it for those who haven't seen it, but it's amazing what details we can miss when we aren't looking for them. I suspect this is made even worse when we're casually viewing videos in a disjointed way as on social media and we're not even giving one part of the video our full attention. 1. [this video]
Famous example of missing details when not looking
@nyrikki Jan 2025 Cites it
on HN thread Allstate used GasBuddy and other apps to track driving behavior: lawsuit
Never made that claim, but dawn and dusk are the most risky. Mine happened on a lunch break, can't see through rock either. But you only see a fraction of the wildlife that is there. If your sole stratagy is to see them you may be surprised how many deer hit the sides of cars. Complacency and selective attention are very real human problems. The classic basketball game example of selective attention if you don't buy it. [this video]
Classic basketball example of selective attention
@Joel_Mckay Jul 2025 Cites it
on HN thread How Tesla is proving doubters right on why its robotaxi service cannot scale
It is true most humans can not track more than 5 objects concurrently. However, lidar data sets tend to produce sparse unambiguous point cloud data that is a lot more feasible to process. For example, a picture/reflection of a road on a bus is not a viable option with 3D data. Cheers =3 [this video]
Shows human limits tracking multiple objects

Video list and Hacker News comment labels from HackerTube (prompted by @karpathy), released under ODC-By 1.0, built on the open-index/hacker-news archive. Hacker News data is provided by Y Combinator; comments remain the work of their authors. Video titles, channel names and thumbnails belong to their creators and are shown via YouTube. HackerTube Watch is an unofficial edition. Data export of 2026-10-31.

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