Things I'm interested in...
My primary interest lies in visual perception and in its underlying brain mechanisms. Specifically, I'm interested in the neural correlates of high-level vision, such as face, object and scene processing. I mainly use fMRI, M/EEG and behavioral approaches to investigate the organization and functional properties of high-level visual cortex. Below you can find a selection of specific projects.
Real-world structure and efficient natural perception
Visual information in real-world environments is structured. The world around us consists of separable objects that do not appear in random positions in space, but adhere to recurring regularity structures, which depend on physical constraints, an object’s functional properties, and by typical relationships between multiple objects. Using a combination of M/EEG recordings and functional MRI, the project aims for a better understanding for how such regularity structures shape object and scene processing in the visual system. Combining these neural data with behavioral experiments, the project will reveal how visual perception in everyday situations benefits from the regularities contained in real-world scenes.
Relevant Publications:
Kaiser, Quek, Cichy, Peelen. (2019) Trends Cogn Sci.
Kaiser, Cichy. (2018) Cognition.
Kaiser, Cichy. (2018) J Neurophysiol.
Kaiser, Moeskops, Cichy. (2018) Neuroimage.
Kaiser, Peelen. (2018) Neuroimage.
Kaiser, Haselhuhn. (2017) J Neurosci.
Stein, Kaiser, Peelen. (2015) J Vis.
Kaiser, Stein, Peelen. (2015) Psychon Bull Rev.
Kaiser, Stein, Peelen. (2014) Proc Natl Acad Sci USA.
Attentional Selection in Natural Scenes
Despite the cluttered nature of real-world scenes, humans are strikingly efficient in selecting behaviorally relevant objects over irrelevant, distracting objects (e.g., when driving on the road). Using visual detection tasks and multivariate decoding of MEG data, we have related this efficiency to a rapid prioritization of task-relevant object category information in visual cortex. This early attentional enhancement of visual information forms a neural correlate of successful selection behavior in everyday environments.
Relevant Publications:
Battistoni, Kaiser, Hickey, Peelen. (in press) Cortex.
Kaiser, Oosterhof, Peelen. (2016) J Neurosci.
Hickey, Kaiser, Peelen. (2015) J Exp Psychol Gen.
Organization of High-Level Visual Cortex
Regions in high-level visual cortex have been associated with preferential processing of visual category information. It is a debated question whether such visual category representations reflect category-associated visual features (e.g., shape properties that are typical for a specific category), or whether these representations are genuinely categorical, and thus somewhat detached from visual properties. Using fMRI and MEG decoding approaches, we showed that category representations cannot be reduced to visual (shape) similarity and that shape- and category-representations co-exist in high-level visual areas.
Relevant Publications:
Proklova, Kaiser, Peelen. (2019) Neuroimage.
Kaiser*, Azzalini*, Peelen. (2016) J Neurophysiol.
Proklova*, Kaiser*, Peelen. (2016) J Cogn Neurosci.
Person Perception
Perceiving the people around us is key for our everyday lives, from recognizing individuals to understanding social interactions. Person perception is mediated by a set of specialized cortical mechanisms. In my research, I try to understand how these mechanisms support the extraction of meaningful person characteristics (e.g., whether we see a man or a woman, or whether we know a specific person or not) from sensory signals, and how this information varies across brain regions and across temporal scales.
Relevant Publications:
Ambrus*, Kaiser*, Cichy, Kovács. (in press) Cerebral Cortex.
Kaiser*, Strnad*, Seidl, Kastner, Peelen. (2014) J Neurophysiol.
Kaiser, Walther, Schweinberger, Kovács. (2013) J Neurophysiol.
Walther, Schweinberger, Kaiser, Kovács. (2013) Cortex.
Kovács, Kaiser, Kaliukhovich, Vidnyánszky, Vogels. (2013) J Neurosci.