Our 1st (Annual?) Global Lab Meeting

The entire lab, except for Dr Elisa Infanti who for practical reasons already visited New Zealand in 2018, got together for the first time in Auckland. We were joined by Dr David Carmel of Victoria University of Wellington. We started off the day with short presentations by all the students, followed by longer discussions. After that we went to have lunch in a café in the heights of the Waitakere Ranges. OLYMPUS DIGITAL CAMERA

Then we drove through the clouds out west to Karekare Beach for a walk leaving people to discuss freely (David and Sam talked at great length about replications and open reviewing).

As good vision scientists, we checked out the waterfall there for another real-life demonstration of the motion aftereffect. This successfully replicated the work of Kalpadakis-Smith, Schwarzkopf & Greenwood (2018) at ARVO.

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These two people are randomers and probably had no useful insight into the replication crisis or open reviewing whatsoever

To conclude, we all went to Sam’s place to have drinks on the deck until late in the night, where we were joined at some point by a possum visitor (nasty invasive species bent on destroying the local wildlife but still bloody cute).

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Again, very sorry Elisa and other postdoc incarnations, Christina, Ben, and Nonie couldn’t join us. But we need to have more gatherings like this in the future!

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Elisa visiting Auckland

Dr Elisa Infanti is the first person from the London lab visiting the Auckland lab for about three weeks. We have already attended the ACNS 2018 conference in Melbourne. This coming Friday the two of us will be giving the Cognitive Neuroscience seminar in the Science Centre of the University of Auckland.

Elisa-in-Auckland

Strange case of unexplained vision loss

Dr Christina Moutsiana and a team of collaborators published a case study of a person who has suffered unexplained vision loss. Despite showing no evidence of any problems or dysfunction in her early visual pathway and pretty much normal retinotopic maps in the visual cortex, she has progressively lost her vision. The scotoma grew mostly in a clockwise fashion across her visual field without respecting the meridians, which would typically be a sign of a cortical source of the vision loss. In addition, she has severe deficits with visual processing, especially any visual functions that involve spatial integration, such as contour integration, illusory shapes, or detecting global motion. We cannot explain this pattern of results but it is a very interesting case that should be part of the scientific literature.

CW-Visual-Fields

Moutsiana, C, Soliman, R, de-Wit, L, James-Galton, M, Sereno, MI, Plant, GT, & Schwarzkopf, DS (2018). Unexplained progressive visual field loss in the presence of normal retinotopic maps. Frontiers in Psychology 9: 1722.

Optimal design for MAPS experiments

Dr Nonie Finlayson published a series of experiments in which we explore the optimal design for experiments using our Multiple Alternatives Perceptual Search (MAPS) task for estimating perceptual biases at several visual field locations. We show that the MAPS task does not tend to result in a decision bias to select the middle of the candidate range but that feedback after every trial modulates estimates of perceptual biases.

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Finlayson, NJ, Manser-Smith, K, Balraj, A, de Haas, B, & Schwarzkopf, DS (2018). The optimal experimental design for Multiple Alternatives Perceptual Search. Attention, Perception & Psychophysics

Thatcher illusion and facial features

Dr Benjamin de Haas published a study in the Journal of Vision in which he followed up his previous work on retinotopic priors in face perception. We are used to seeing eyes in the upper visual field and mouths in the lower visual field. His experiments suggest that this could explain at least some of the Thatcher illusion. This argues against a strict role of holistic processing in that illusion.

Thatcher Illusion
The Thatcherized face (top right) appears grotesque but when inverted (bottom left) it is far less so

 

de Haas, B, & Schwarzkopf, DS (2018) Feature-location effects in the Thatcher illusion. Journal of Vision 18(4): 16.

Escher Chairs illusion

Nick Scott-Samuel, George Lovell, Hiroshi Ashida, and Sam published a (very) little article on the Stacking Chairs illusion in iPerception. This was all mainly Nick’s work who discovered that stacking those kinds of chairs produces a very confusing and seemingly geometrically impossible percept:

EscherChairs

Note, a reviewer didn’t like that we called this stimulus Escher Chairs but I will stubbornly continue calling them that. They are very Escherial. Or perhaps Penrosian would be more appropriate?

Scott-Samuel, NE, Ashida, H, Lovell, PG, Meese, TS, & Schwarzkopf, DS (2018). Stacking Chairs: Local Sense and Global Nonsense. i-Perception 9(1).

pRF study on illusory contours

Dr Benjamin de Haas and Sam recently published a study in Scientific Reports using illusory contour and amodal completion (occlusion) stimuli to map population receptive fields in early visual cortex. The signals are very weak but they correspond spatially very well to normal retinotopic maps. We suspect that what these experiments were really mapping is spatially selective attention cued to the position of the mapping stimuli. We thank Rebecca Tyrwhitt-Drake who did the original experiments for her student research project.

Kanizsa

de Haas B, & Schwarzkopf DS (2018). Spatially selective responses to Kanizsa and occlusion stimuli in human visual cortex. Scientific Reports 8: 611.

End of an era

Last photo of the lab before Sam’s move to New Zealand. I hope we can all meet again soon on the same spot of earth wherever it may be!

 

LabBeforeNZ

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