Sam Schwarzkopf

Coming to APCV & EPC from outside of Auckland, New Zealand? Here is some more information about Student Travel Awards.

More available on our website:
visualneuroscience.auckland.ac.nz/epc-apcv-2026/

The Australasian Experimental Psychology Conference (EPC) and Asia Pacific Conference on Vision (APCV) are holding a joint meeting in 2026, to be held at the University of Auckland from July 1-4. Abstract submissions now open!
visualneuroscience.auckland.ac.nz/epc-apcv-2026/

📢 Workshop announcement.

We are super excited to announce the workshop Perceptual Inferences, from philosophy to neuroscience, organized by Alexander Schütz and Daniel Kaiser.

📍 Rauischholzhausen Castle, near Marburg, Germany
🗓️ June 8 to 10, 2026.
1/4

Three days left to submit symposium, workshop, and satellite ideas for EPC-APCV in Auckland in July.

Symposia will run alongside talk sessions during the conference, and workshops/satellites will run on the first day, before the welcome ceremony.

Come to Auckland in July 2026 for the joint meeting of the Australasian Experimental Psychology Conference and the Asia Pacific Conference on Vision!!

STUDENTS: there will be 40 travel support awards of $500 to help you attend, so don't let the distance stop you from attending.

Very proud and pleased that Poutasi Urale, the first PhD student I supervised since starting in Auckland has now graduated! Good way to start the holidays! 🙂🎓
(And no, this is not my academic gown...)

Mistakes happen. All the time. To err is human etc. But I strive to make fewer stupid mistakes. If anyone has any good ideas how to do that, let me know... All I know is that checking your work apparently isn't enough 😏

Be that as it may. This issue has been dealt with & hopefully no harm was done. But I'd bet there are many such errors in the literature. I know I have made mistakes in descriptions or equations before. And I know some stats papers where the authors told me the published equation was wrong...

As it happens, I know that in at least one of our papers we did this but then had a reviewer tell us to explain the NC calculation. I can't say if it was one of these two or another paper, but the reason the offending sentences were in it are definitely because of this. Which is a bit annoying...

That said, given we didn't create these methods for these studies, there was no real reason to explain them in detail. We could have simply cited the earlier studies. The way I see it, this would've been better. Not only would it avoid stupid mistakes but it would make the methods more concise.

Of course, there are good reasons to have a verbal description (or mathematical notation) of the methods. It makes it more future proof, because some code won't run anymore on future computers etc. And you could rightly say that people need to pay more attention to how they write their methods...

But this makes me wonder - in this digital age in which we share our code & data - wouldn't it be better to avoid describing our methods in prose altogether? Methods sections exist to permit independent replication but that technically would involve running our code, not translating text to code.

As senior author of both studies, I take the ultimate responsibility for the error (& there is a good chance I wrote the offending sentence in the first place). Yes, everyone in the know should theoretically be able to spot it - but clearly this is not always how it works...

Another & more detailed explanation can be found in van Bree et al.'s excellent preprint - so I'll leave it at that.
But on a general note: The erroneous statements in our articles slipped past all the authors & reviewers & editors of 2 papers. It is easy to miss even stupid mistakes...

I won't go into detail on how this textual error arose - that would only confuse matters further. Instead I'll note that when we first introduced the noise ceiling in our toolbox, we explained the calculation in a publication by Catherine Morgan & myself: f1000research.com/articles/8-1...

Correction to: ‘Perceiving object size in pictures involves high-level processing’ (2025), by Altan et al. Proc. R. Soc. B292, 20242967 (Published online 14 May 2025). (https://doi.org/10.1098/rspb.2024.2967).

However, in 2 recent publications from the lab we incorrectly described what our code does. It was a stupid oversight but it's important. To prevent people making a mistake based on this, both these articles have now been officially corrected:
doi.org/10.1098/rspb...
doi.org/10.7554/eLif...

I'm slightly annoyed (& embarrassed) because recently we inadvertently added to this confusion. I hasten to point out that we did -not- make this error. Our pRF analysis toolbox calculates the NC & our calculation is correct. In fact, to avoid confusion our analysis code explicitly states this...

If you calculated noise ceilings (NC) based on split-half reliability - e.g. to compare models - this one is important!
Seems many published studies miscalculated it, overestimating model performance. First, let's make this crystal clear:

NC = 2*r / (1+r)

where r is split-half correlation.

🤣

Deadline for Symposia & Workshop submissions: 31 January 2026
General abstracts: Rolling acceptance until 30 April 2026

This year we will offer up to 40 travel awards (500AUD) to help students attend the conference, given on basis of need. Applicants must submit abstracts by 27 February 2026.

It is our great honour to announce the APCV Keynote at #epc-apcv-2026: Prof. Hakwan Lau from the Institute for Basic Science in Korea!
The call for member-initiated symposia & abstracts is now open: visualneuroscience.auckland.ac.nz/epc-apcv-2026

#psychscisky #visionscience #neuroskyence

Auditory illusions: new research discovers how our ears play tricks on us Without visual clues, our ears mishear sounds produced in front of us. Knowing more about why this happens will give new insights into how the brain works.

Here is a short piece in the Conversation about the Spoon Illusion: doi.org/10.64628/AA....

#psychscisky #neuroskyence but not-really #visionscience

😏

I attempted an experiment on this during my Bedford Way days actually (in a sound-proof room no less!) but that turned out too complicated. I realised that for this we would first need to 1) replicate the late-night-goofing-around conditions and 2) have some dedicated students to do the work 🙂

Let me present the Spoon Illusion 🙂🥄

This has been in the works for over a decade when we were just goofing around testing sound localisation in my in-laws' kitchen... But we finally managed to do some reasonably controlled experiments on this. #psychscisky #neuroskyence
doi.org/10.1177/0301...

In this preprint, we concurrently fit the HRF alongside pRF parameters doi.org/10.1101/2025...

- HRF varies between visual areas
- HRF also varies with pRF stimulus designs (due to nonlinearities?)
- Esp. when fitting complex models this can skew results a lot!

#visionscience #neuroskyence

Hiroshi Ashida just suggested that to me too - you're both right. The effect appears to be due to a depth order effect so has nothing to do with the implied perspective. When the lines both extend across the triangle borders (and thus look like they are in front of it) the depth percept disappears:

Yes that's how it looks to me anyway. Although perhaps it's less strong in the latter examples than with the triangles? We'd need to test this properly to know for sure of course.

...or even triangles in a classical Ponzo illusion. The whole thing is even more mysterious than I initially thought! 🤔🧐