Reduced visual acuity and stereopsis are common symptoms of amblyopia. Previous studies have demonstrated that motor function is also impaired in patients with amblyopia. Binocular training methods may improve not just visual acuity of the amblyopic eye, but stereopsis and motor function. This pilot study investigated how a binocular contrast discrimination training method may improve these functions in patients with amblyopia, and compared their thresholds to a control group. Furthermore, the differences between amblyopic patients with alternate fixation and those without it were investigated. Patients with amblyopia underwent five sessions of training, each lasting around 90 min. Participants viewed a dichoptic stimulus through a stereoscope, forcing them to fuse the images and use both eyes co-operatively. Participants saw Gabor patches in two successive trials, with a target Gabor shown in only one interval for the non-dominant eye. The dominant eye saw a mask Gabor patch for both intervals. Participants continually were tasked with determining which had the higher contrast until a threshold was reached. Results varied depending on the type of amblyopia, as two of the four patients had alternating fixation. Some patients showed improvements in visual acuity and/or stereopsis, but there were no overall improvements in motor function. This training may be beneficial, even for patients with strabismus who have difficulties with consistent fusion.

We investigated whether visual processing in two-dimensional (2D) space also works in three-dimensional (3D) space using virtual reality (VR) on head-mounted displays, to examine the feature integration theory. In Experiment 1, participants performed a visual search task using 3D items in VR. The search gradients were flat for color-feature search and steep for shape-feature and conjunctive searches. In Experiment 2, two objects with the same visual angle were presented at different distances in VR, and participants from Experiment 1 performed a distance discrimination task using binocular depth cues. Results showed that the shorter the observing distance and the larger the distance difference between the two objects, the more accurately participants discriminated, suggesting 3D perception in VR. In Experiment 3, to investigate whether the inefficiency in shape-feature search in VR was due to retinal heterogeneity among the distractors, other participants performed a visual search task using 3D items on a 2D monitor and showed more efficient shape-feature search. We discussed this result within the framework of the guided search model and concluded that visual processing revealed in 2D also works in 3D.

The Concealed Information Test (CIT), a unique polygraph method used in Japanese criminal investigations, is based on “memory detection” rather than “lie detection.” CIT utilizes autonomic nervous system responses to distinguish between a crime-relevant and irrelevant questions, demonstrating high effectiveness with low false-positive rates. The theoretical framework has evolved from orienting response theory to response fractionation theory, which proposes two distinct mechanisms: a “recognition process” and a “concealment process” involving arousal inhibition. Brain functional measurement techniques have gained attention for investigating these cognitive processes. A temporally-synchronized measurement system combining functional near-infrared spectroscopy (fNIRS) with autonomic indicators was developed. Experimental results using mock crime paradigms confirmed crime-relevant response patterns, with synchronized skin conductance elevation and significant increases in oxygenated hemoglobin concentration in the right inferior frontal gyrus. Temporal region activity preceded prefrontal activity, supporting the sequential cognitive processing flow predicted by response fractionation theory. This research contributes to CIT’s theoretical foundation while representing an important step toward establishing more scientifically-grounded criminal investigation methods.

With significant advances in neuroimaging research, the neural basis underlying decision-making in unethical behavior is gradually being elucidated. In particular, studies on individuals diagnosed with antisocial personality disorders, specifically psychopathy, provide valuable evidence regarding the neural mechanisms of unethical behavior. This conference paper presents an overview of the psychological and neuroscientific characteristics of psychopathy reported in previous research and introduces the author’s study on the neural basis of unethical behavior, conducted with incarcerated individuals diagnosed with psychopathy in the United States. Furthermore, the limitations of recent research on psychopathy are examined, and future directions for studies on neuroscience and criminology are discussed.

Severe traumatic experiences—particularly those involving criminal victimization—can trigger a range of stress responses and, in more serious cases, lead to the development of post-traumatic stress disorder (PTSD). The diverse symptoms of PTSD have been increasingly understood as forming distinct clusters, each associated with unique neural substrates. Based on these findings, the concept of a “dissociative subtype” of PTSD has been introduced in the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition) by the American Psychiatric Association. In dissociative PTSD, excessive inhibition of the amygdala by the ventromedial prefrontal cortex (vmPFC) is observed—markedly different from the hyperactivity of the amygdala typically seen in conventional PTSD. While conventional PTSD symptoms can be characterized as a “fear ON” state, dissociative symptoms can be viewed as a “fear OFF” state. These antagonistic symptom profiles should be conceptualized not as separate clusters, but rather as opposing patterns within a unified framework. To capture this structure, we have adopted a dimensional approach, organizing symptoms along a small number of key axes. In this article, we examine the neural and biological bases underlying these dimensions and their dynamics, with a particular focus on the “Reciprocal Inhibition Model” proposed by the author. Finally, we discuss how comparisons between the neural dynamics of offenders and those with PTSD may shed light on the intergenerational cycle of abuse and the propagation of criminal behavior.

Prof. Moshe Bar (Bar-Ilan University) gave a lecture titled “Our Wander-Full Minds” in a hybrid event on October 20, 2024 as the 2nd Forum of the Japanese Psychonomic Society. Prof. Bar is an internationally renowned cognitive neuroscientist whose innovative research has made revolutionary contributions to the understanding of perceptual, cognitive, and psychiatric issues. His book “Mind Wandering” (2022), a Japanese translation of his major research findings, was published in December 2023. In his lecture, he not only explained the contents of “Mind Wandering,” but also looked back on the history and development of his research over the years, and explained it from the perspective of the underlying brain information processing. The essence of many of the findings mentioned in his book “Mind Wandering” was conveyed in this lecture. We hope that this lecture will help members of this Society to understand how to position and develop “Mind Wandering” from the viewpoint of psychonomic sciences.

This note provides a brief overview of the activities undertaken by the Young Researchers Committee of the Japanese Psychonomic Society (JPS) during the 2023–2024 academic year. The committee’s main activity in this period was holding oral sessions at the JPS annual meeting to present the Young Psychonomic Scientist of the Year award. We also organized a social networking event at the annual meeting where young researchers could get to know each other better. Furthermore, we are currently involved in an initiative to connect with branches of other societies for young researchers, with the aim of facilitating their activities. We will continue to develop new activities targeting a broader range of young and early-career researchers.