Computational Psychology

at Technische Universität Berlin

We study human visual perception using both experiments and computational modeling. We, humans, explore the visual world with our eyes and visual impressions constitute large parts of our perceptual experience. We still do not understand how perceptual experiences arise from a given sensory stimulation and maybe we never will. Nonetheless we study visual perception with psychophysical experiments. For example, we ask observers whether they perceive depth in images like the one shown on the right. We formulate computational models to account for the perceptual judgments observers make. We also revise and develop experimental techniques to probe observers' perceptual experiences.
Bridget Riley "Disfigured"






News

Joris’, Marianne's and Guillermo's paper "What Fechner could not do: Separating perceptual encoding and decoding with difference scaling" has been published in Journal of Vision

Here you can find Joris', Marianne's and Guillermo's paper on "What Fechner could not do: Separating perceptual encoding and decoding with difference scaling". It has been published in Journal of Vision, May, 2024. You can also find it following this doi:10.1167/jov.24.5.5 .


Lynn’s, Felix' and Marianne's paper "Standard models of spatial vision mispredict edge sensitivity at low spatial frequencies" has been published in Vision Research

Here you can find Lynn’s, Felix' and Marianne's paper on "Standard models of spatial vision mispredict edge sensitivity at low spatial frequencies". It has been published in Vision Research, 222, 2024. You can also find it following this doi .


New group members: Hannah Boldt, Sebastian Keil, Duc Phan Anh Le, Azer Mahjoub, Yiran Sun, Rhea Widmer and Konstantinos Zamanis

We are very happy to welcome our new group members Hannah Boldt , Sebastian Keil , Duc Phan Anh Le , Azer Mahjoub , Yiran Sun , Rhea Widmer and Konstantinos Zamanis to our group. In her Bachelor thesis, Hannah investigates at which point does noise masking cause a layer scission. In his Bachelor thesis, Sebastian studies two models of brightness perception - ODOG and BIWaM. The focus is to identify the differences between them. Duc investigates the noise masks’ effectivity in Großmann’s experiments on edge detection in his Bachelor thesis. Azer studies Weather's Cinematic Influence: Analyzing the Genre Preferences in his Bachelor thesis. In his Bachelor thesis, Yiran investigates edge detection in natural images under various noise masks using a spatiotemporal model. Rhea studies improving trial selection for maximum likelihood conjoint measurement for psychophysical experiments in her Bachelor thesis. In his Bachelor thesis, Konstantinos studies monitor calibration with unstable gamma function due to temperature dependency.


Student Symposium in June 2024

Our BA-students Hannah , Tim H., Tim S. , Philip , Clara , Daniel , Sebastian and Azer proudly present their theses work in our student symposium. If you want to know more about their exciting research topics join us on Friday, June 21, from 9am-3pm in MAR 5.013. If you missed it you can check out the presentations under their names.


New group members: Philip Brozicevic, Daniel Castro Sanchez and Tim Henze

We are very happy to welcome our new group members Philip Brozicevic , Daniel Castro Sanchez and Tim Henze to our group. In his Bachelor thesis, Philip investigates to what extent contour segmentations of different observers are consistent and what role the type of noise plays in this. Daniel studies the investigation of brightness contrast perception: A comparison between e- and traditional paper and monitors in his Bachelor thesis. Tim studies frequency manipulation in complex images and evaluate an algorithm from Marius Krause's bachelor's thesis for controlling image contrast in his Bachelor thesis.


New group members: Navdha Jain, Clara Ollech and Tim Schlesier

We are very happy to welcome our new group members Navdha Jain , Clara Ollech and Tim Schlesier to our group. In her Bachelor thesis, Navdha focuses on measuring the perceptual scales in brightness assimilation effect. Clara studies how different parameters in stimuli influence the performance of computational models and where exactly these models differ in her Bachelor thesis. In his Bachelor thesis, building on an earlier Bachelor thesis by Savas Großmann, Tim studies whether visual perception is more sensitive to edges or differences in brightness.


Teaching at the Summer School 15th Advanced Scientific Programming in Python 2023

Image of Summer school ASPP 2023 at Heraklion

Guillermo taught this August in the Summer School 15th Advanced Scientific Programming in Python (ASPP), in Heraklion, Greece. He lectured on the best practices of data visualization, and on advanced numpy, the most used library for scientific computing in python. The school was a success, hosting 30 students around Europe from diverse scientific disciplines.


Teaching at the 1st Advanced Scientific Programming in Python – Latin America 2023

2023_Guillermo_Aguilar_Teaching_Mexico

Guillermo participated as tutor in the 1ˢᵗ Advanced Scientific Programming in Python (ASPP) - Latin America 2023, in Mexico City. The school taught a selection of advanced programming techniques and best practices to scientists who do not have formal training in programming. Specifically, he lectured on best practices of data visualization and advanced numpy. You can find more information in the school's website here . And here you can find a written news article about the school (in Spanish) .


Student Symposium in June 2023

We are happy that we had our BA student symposium in the middle of the summer semester! Our BA candidates Ji , Hafidz , Felix , Lisa and Jan presented their diverse set of research questions and we were happy to see their progress.



New group members: Hafidz Arifin, Felix Dexel, Ji Hyea Park, Lisa Scheibner, Jarl-Sebastian Sorensen and Jan Zabel

We are very happy to welcome our new group members Hafidz Arifin , Felix Dexel , Ji Hyea Park , Lisa Scheibner , Jarl-Sebastian Sorensen and Jan Zabel to our group. In his Bachelor thesis, Hafidz focuses on two different methods to study human brightness perception - method of adjustment and brightness ratings. Felix studies how the brightness of surfaces is represented in the brain in his Bachelor thesis. In her Bachelor thesis, Ji Hyea studies the difference between real and computer-generated stimuli in the domain of lightness perception. Lisa studies in her Bachelor thesis what perceptual scales for simultaneous brightness contrast look like and how to compare them with those of White's effect. Jarl workes with us as a Student research assistant. He studies the influence of noise on human edge perception in natural images and Jan studies how to optimize data acquisition for scaling methods, in particular for MLCM in his Bachelor thesis.


Student Symposium in January 2023

We are happy to finish the winter semester with our BA student symposium! Our BA candidates Savas , Sam , Marius, Marc and Filipe presented their diverse set of research questions and we were happy to see their progress.


New group members: Filipe Borges, Sam Chamani, Savas Großmann, Marius Krause, Karol Rogoza and Marc Tukendorf

We are very happy to welcome our new group members Filipe Borges , Sam Chamani , Savas Großmann , Marius Krause , Karol Rogoza and Marc Tukendorf to our group. In his Bachelor thesis, Filipe studies surface segmentation through adaptation. Sam studies perception of transparency and contrast in variegated checkerboards with transparent media of low luminance values in his Bachelor thesis. In his Bachelor thesis, Savas studies if the human visual system is more sensitive to edges or luminance differences and if we do get similar results from experiments on these two stimuli. In his Bachelor thesis, Karol studies visual perception of depth through different illuminations of 3d generated scenes on the computer screen. And Marc focuses on replicability and reproducibility: Translating and evaluating a camouflage detection algorithm in his Bachelor thesis.


Marianne’s and Lynn’s paper "Fixational eye movements enable robust edge detection" has been published in Journal of Vision (JOV)

Maertens and Schmittwilken (2022

Here you can find Marianne’s and Lynn’s paper on "Fixational eye movements enable robust edge detection". It has been published in Journal of Vision (JOV).


Student Symposium in July 2022

We are happy to finish the summer semester with our BA student symposium! Our BA candidates Anas , Enis , Marius, Karol, Eduardo, Hendrik and Jarl presented their diverse set of research questions and we were happy to see their progress.


New group members: Burak Kiran, Iris Özkaya, Eduardo Luiz Rhein and Enis Can Simsek

We are very happy to welcome our new group members Burak Kiran , Iris Özkaya , Eduardo Luiz Rhein and Enis Can Simsek to our group. In his Bachelor thesis, Burak will focus on the relationship between discrimination and scaling methods in the domain of contrast perception. In her Bachelor thesis, Iris studies the effect of background contrast on perceived contrast and perceived transparency. In his Bachelor thesis, Eduardo studies implementing and analyzing content-adaptive subsampling for image compression. Enis studies contrast constancy with supra-threshold contrast using MLCM in his Bachelor thesis.


MODVIS 2022

Marianne , Guillermo and Joris have attended MODVIS 2022!! Here you can find Marianne’s, Guillermo’s and Joris’ talk on "Constraining computational models of brightness perception: what’s the right psychophysical data?" And here you can find the slides .


Preprint of Marianne’s and Lynn’s paper "Fixational eye movements enable robust edge detection" (will be published soon in JOV)

Here you can find the preprint of Marianne’s and Lynn’s paper on "Fixational eye movements enable robust edge detection". It will be published soon in Journal of Vision (JOV).


Annual meeting of the Vision Science Society 2022

Marianne , Guillermo , Lynn and Joris have attended the VSS annual meeting 2022!! Here you can find Marianne’s, Guillermo’s and Joris’ poster and here is Marianne’s and Lynn’s poster .


Codary job advertisement

Codary Logo

The TU alumni startup Codary is currently looking for motivated students (Werkstudenten) to teach children programming online. The position can be done completely remotely and the hourly wage is 13EUR/h. More information can be found here .


New group members: Jarl-Sebastian Soerensen, Hendrik Schulze Bröring and Anas Allaham

We are very happy to welcome our new group members Jarl-Sebastian Soerensen , Hendrik Schulze Bröring and Anas Allaham to our group. In his Bachelor thesis, Jarl wants to investigate the influence of noise on human edge perception in natural images. Hendrik explores in his Bachelor thesis how size reduction of input stimuli affects the output of multiscale spatial filtering models. In his Bachelor thesis, Anas focuses on the study of brightness and its entangled relationship with perceptual phenomena in a practical setting.


New publication in Journal of Vision

Aguilar and Maertens (2022)

Marianne's and Guillermo's paper entitled "Conjoint measurement of perceived transparency and perceived contrast in variegated checkerboards" was published in the February's 2022 issue of Journal of Vision. You can find it following this link.


New group members: Yasin Mehmet Cifci, Poulami Ghosh, Jakob Grünwald, Tom Ravid Hausmann, Marie-Elisabeth Makohl and Annalena Katharina Schillen

We are very happy to welcome our new group members Yasin Mehmet Cifci , Poulami Ghosh , Jakob Grünwald , Tom Ravid Hausmann , Marie-Elisabeth Makohl and Annalena Katharina Schillen to our group. Yasin Mehmet works for us as a Student research assistant. He works on brightness perception models. Poulami is a Master student. As part of her lab rotation she does experiment to investigate whether human brightness perception can be done with online experimental tools. Jakob is a Bachelor student. In his Internship Jakob studies stochastic dependencies in scaling methods, in particular MLDS. Ravid is a Bachelor student. He works on expanding and refactoring the multyscale package for greater transparency in brightness perception modelling. Marie-Elisabeth works for us as a Student research assistant. She studies easy evaluation and comparison of brightness perception models. Annalena is a Bachelor student.


Nov, 4, 2021: Teaching live again!!! TU students are the best ;-)

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We congratulate Lynn for winning the ECVP 2021 poster award

We are happy to congratulate Lynn that the ECVP 2021 poster award sponsored by PeerJ goes to Lynn for her work entitled "An active model of human edge sensitivity: Extracting edges via fixational eye movements". You can find Lynn's poster here Please find here the blog post, i.e. the interview with Lynn


ECVP 2021

Joris Lynn and Matko are happy to present their posters at virtual ECVP 2021!! Here you can find Joris poster and You can find Lynn's poster here and Matko's poster here


New group member: Nico Kestel

On June 2021, Nico Kestel joined us in our group. In his Bachelor thesis, Nico wants to explore how CNNs might benefit from using dynamic images derived from fixational eye movements instead of static images to recognize objects in naturalistic scenes.


PsyCo goes Lange Nacht der Wissenschaften!

Interested in a fun evening with Science of Intelligence as part of the Lange Nacht der Wissenschaften 2021? Then sign up here for the Science Pub Quiz this Saturday, June 5th from 7.30-10 pm!

What is intelligence? Do beets float in water? Why should you pet your basil? Aravind Battaje and our lab member Lynn Schmittwilken will tell us about their latest research and answer your most burning questions about how humans and computers can perceive the world. The event will be held in English and German and is aimed at scientists and non-scientists alike. We are looking forward to seeing you!


Annual meeting of the Vision Science Society 2021

Joris Lynn Marianne and Max are happy to present their posters at virtual VSS!! We are looking forward to the annual meeting of the Vision Science Society! Here you can find Joris poster and here is Lynn’s poster and Marianne’s and Max poster


New group member: Wenwen Zhang

On April 2021, Wenwen Zhang joined us in our group. Wenwen studies the relationship between apparent contrast (supra-threshold discriminability) and contrast sensitivity (contrast discrimination thresholds) in human observers in her Bachelor thesis.


Carolin Brunn sucessfully defended her Bachelor thesis

We congratulate Carolin Brunn!! She successfully defended her Bachelor thesis on The Crispening Effect: An Artefact of a Method or a Feature of the visual System and moves on to her Master studies in Computer Science and to teaching computing to students. For more information about the program please click here


New group members: Amanda Maiwald, Christian Wohlhaupt and Matti Zinke

On April 2021, Amanda Maiwald Christian Wohlhaupt and Matti Zinke joined us in our group. Amanda explores gamification in the context of programming education in her Master thesis. Christian researches in his Bachelor thesis potential differences in the aesthetic perception of sunset-pictures by people of different geographic origin for marketing purposes. Matti Zinke is a Bachelor student at the TU Berlin.


PsyCo goes Girls' Day!

Have you ever wondered what the everyday worklife of a vision scientist might look like? One of our lab members, Lynn Schmittwilken, will talk about exactly this topic with a group of young girls during this year's Girls' Day on 22 April 2021 to encourage more girls to become vision scientists. For more information about the event, have a look here !


New group member: Marcus Bindermann

On April 2021, Marcus Bindermann joined us in our group to work on his Bachelor thesis project. Marcus is a Bachelor student in Computer Sciences at the TU Berlin.


Lynn Schmittwilken has been awarded a 2021 FoVea Travel and Networking Award!

We are happy to congratulate our lab member, Lynn Schmittwilken, for being awarded a 2021 FoVea Travel and Networking Award !


On 18 March 2021, Scholar Minds will talk about "Becoming aware through mindfulness" during the Brain Awareness Week 2021.

On Thursday, 18th of March, at 5pm Scholar Minds invites you to an online event about mindfulness and mental helath during the doctorate. Scholar Minds is a PhD initiative based in Berlin with the mission to help other PhD students to achieve a better mental health and work-life balance. Pursuing a doctorate is an exceptional time with great opportunities like investigating a phenomenon no one ever did before or discussing your research with new people from all over the world. But are you aware that this exceptional time also harbors exceptional dangers to your mental health? Are you aware that you as a PhD student are six times more likely to suffer from anxiety and depression? During the event, we will talk about mental health struggles related to the doctorate and introduce you to a tool to become more resilient: mindfulness. Mindfulness is a simple meditation tool that can help you to increase your mental well-being.

During the event, the mindfulness expert Dr. Simon Guendelman will present the concept of mindfulness and latest findings from (neuroscientific) research. On top, he will take us onto a little journey to become more aware about ourselves through mindfulness.

Register here: https://forms.gle/YpwcfRBkGGxy6Yhu5


New group member: Matko Matic

On March 2021, Matko Matic joined us in our group. Matko is a Master student in Information Systems and Signal Processing at KU Leuven. Currently, he is doing an Erasmus at the TU Berlin. He will support us as a research assistant (HiWi).


On 26 November 2020, Professor Michele Rucci (University of Rochester) gave a talk at the SCIoI Distinguished Lecture Series.

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Establishing a representation of space is a major goal of sensory systems. Spatial information, however, is not always explicit in the incoming sensory signals. In most modalities it needs to be actively extracted from cues embedded in the temporal flow of receptor activation. Vision, on the other hand, starts with a sophisticated optical imaging system that explicitly preserves spatial information on the retina. This may lead to the assumption that vision is predominantly a passive spatial process: all that is needed is to transmit the retinal image to the cortex, like uploading a digital photograph, to establish a spatial map of the world. However, this deceptively simple analogy is inconsistent with theoretical models and experiments that study visual processing in the context of normal motor behavior. In his talk, Michele argued that, as with other senses, vision relies heavily on sensorimotor strategies to extract and represent spatial information in the temporal domain.

You can find an overview on his scientific work here


Yiqun Xiao sucessfully defended Master thesis

Perceived contrast in Chubb et al. (1989) compared to variegated checkerboards.

We congratulate Yiqun Xiao!! She successfully defended her Master thesis titled "Perceived Contrast in Variegated Checkerboards". In her thesis she studied the contrast-contrast effect (Chubb, Sperling & Solomon, 1990) in variegated checkerboards (left image) and compared it to the original effect (right image). Click here if you want to find out more details about her work.


Codary Project

Codary Logo

We congratulate Amanda, Antonia & Nikolaj that their project Codary is supported by one of the coveted Berlin Startup Scholarships since October 2020. Codary is based at the Centre for Entrepreneurship at the Technische Universität Berlin.


New publication in Journal of Vision

JOV animated icon

Marianne's and Guillermo's paper entitled "Towards reliable measurements of perceptual scales in multiple contexts" has published in the April's 2020 issue of Journal of Vision. You can find it following this link.


New group member: Maximilian Pohlmann

On March 2020 Maximilian Pohlmann. joined us in our group. Maximilian is a Bachelor student and will support us as a research assistant (HiWi).


On 12 December 2019, Professor William H. Warren (Brown University) kicked off the SCIoI Distinguished Lecture Series.

SciOI logo

William Warren earned his undergraduate degree at Hampshire College (1976), his Ph.D. in Experimental Psychology from the University of Connecticut (1982), did post-doctoral work at the University of Edinburgh, and has been a professor at Brown ever since.

His research focuses on the visual control of action – in particular, human locomotion and navigation. On the one hand, he wants to understand how motor behavior such as gait and other rhythmic movements are dynamically organized. On the other, he seeks to explain how such behavior is adaptively regulated by visual information in complex environments. Using virtual reality techniques, William H. Warren's research team investigates problems such as the visual control of steering, obstacle avoidance, pedestrian interactions, and collective crowd behavior.


New group members: Joris Vincent, Lynn Schmittwilken, Bernhard Lang and Bianca del Mestre

On November Joris joined us in our group. Joris joined us as a Post-doc. He is from the University of Pennsylvania, Dept. of Neurology. His contact details can be found in People.

On October three new members joined us in our group. Lynn joined us as a Ph.D. student, and she is part of the Science of Intelligence's Doctoral Programm. Bernhard is co-supervised as a Ph.D. student in our lab. And Bianca is our new secretary. Their contact details can be found in People.


ECVP19: we organized a Symposium and contributed with a talk

ECVP 2019 animated logo

Marianne Maertens co-organized the Symposium Maximum Likelihood Difference Scaling (MLDS): Applications and challenges for the European Conference on Visual Perception (ECVP) held last August in Leuven, Belgium. One of the five talks was given by Guillermo Aguilar with the title "Lightness scales measured with MLDS and MLCM in multiple contexts". The abstracts can be found here.