Publications
A collection of my peer-reviewed research publications in neuroscience and cognitive science.
The role of mental imagery in visual ambiguitity: A multi-lab collaborative online test battery. PCI- REGISTERED REPORT
Christodoulou, K., Monzel, M., Krempel, R. A., van Leeuwen, T. M., & Reeder, R. R. • OSF • 2026
Visual perception is a subjective experience that is shaped by cues from the environment,overlearned sensory expectations, and interpretive processes. The theory of divergentpredictive perception states that three factors can predict individual differences in perception:sensory sensitivity likely influences “filling-in” processes such as Gestalt processing, schizotypylikely influences the propensity to see patterns where there are none, and mental imagery – themental simulation of sensory information in the absence of a relevant external stimulus – isproposed to contribute to a richer sensory experience when environmental cues are weaker. Toinvestigate the role of these factors, and particularly mental imagery, in processing visualsensory information with different levels of ambiguity, we will conduct a largescale, multi-lab,online study, with participants spanning across the spectrum of imagery ability – fromaphantasia (absent or weak imagery) to hyperphantasia (superlative imagery). We will presentstimuli with different levels of environmental cues, from Gestalt patterns (strong cues) to randomnoise (weak cues), and account for sensory sensitivity and schizotypy in a high-powered, rapidexperimental design. This study will elucidate the role of mental imagery, sensory sensitivity,and schizotypy in individual differences in perception
The impact of different priors on visual perception: the role of mental imagery and sensory sensitivity. PREREGISTRATION.
Katerina Christodoulou, Reshanne R Reeder, Emiel Krahmer , Tessa M van Leeuwen • OSF • 2025
The present study seeks to investigate how different levels of top-down input affect visual processing in individuals with varying levels of mental imagery ability and sensory processing sensitivity (SPS). Using a multi-paradigm approach, participants will perform tasks that include Mooney stimuli, Müller-Lyer and Ebbinghaus illusions, and the illumination bias. These tasks respectively probe high-level contextual (cognitive) priors and low-level structural (perceptual) priors. By examining these diverse tasks, we aim to elucidate how individual differences in mental imagery and sensory sensitivity influence reliance on prior information and processing of sensory inputs. This research contributes to understanding the nuanced roles of cognitive and sensory factors in visual perception across different populations..
Prolonged grief symptoms and lingering attachment predict approach behavior toward the deceased.
Maarten C. Eisma, Thomas A. de Lang, Katerina Christodoulou, Lara O. Schmitt, Paul A. Boelen, Peter J. de Jong • Journal of Traumatic Stress • 2024
Following the death of a loved one, both approach behaviors related to the deceased (i.e., engagement with feelings, memories, and/or reminders of the deceased) and the avoidance of reminders of the death are theorized to precipitate severe and persistent grief reactions, termed prolonged grief. The “approach-avoidance processing hypothesis” holds that these behavioral tendencies occur simultaneously in prolonged grief disorder (PGD). We tested this hypothesis using a novel free-viewing attention task. Bereaved adults (N = 72, 81.9% female) completed a survey assessing prolonged grief symptoms, depressive symptoms, and lingering attachment and a free-viewing task assessing voluntary attention toward pictures of the deceased and combinations of the deceased with loss-related words (i.e., loss-reality reminders). A main finding was that participants with higher prolonged grief symptom levels, ρ(70) = .32, p = .006, and more lingering attachment, ρ(70) = .26, p = .030, showed stronger attentional focus toward pictures of the deceased. No significant association emerged between either prolonged grief symptom levels or lingering attachment and attention toward loss-reality reminders. The findings suggest that higher prolonged grief symptom levels may be characterized by persisting approach tendencies toward the deceased. Countering excessive proximity-seeking to the deceased in therapy could be beneficial for bereaved adults who show severe and persistent grief reactions.
Time perception in film viewing: A modulation of scene’s duration estimates as a function of film editing. Acta Psychologica.
Lydia Liapi a, Elpida Manoudi b, Maria Revelou a, Katerina Christodoulou a, Petros Koutras c, Petros Maragos c, Argiro Vatakis a • Journal of Neuroscience • 2023
Filmmakers and editors have empirically developed techniques to ensure the spatiotemporal continuity of a film's narration. In terms of time, editing techniques (e.g., elliptical, overlapping, or cut minimization) allow for the manipulation of the perceived duration of events as they unfold on screen.