SignificanceA shared understanding of terminology is essential for clear scientific communication and minimizing misconceptions. This is particularly challenging in rapidly expanding, interdisciplinary domains that utilize functional near-infrared spectroscopy (fNIRS), where researchers come from diverse backgrounds and apply their expertise in fields such as engineering, neuroscience, and psychology.AimThe fNIRS Glossary Project was established to develop a community-sourced glossary covering key fNIRS terms, including those related to the continuous-wave (CW), frequency-domain (FD), and time-domain (TD) NIRS techniques.ApproachThe glossary was collaboratively developed by a diverse group of 76 fNIRS researchers, representing a wide range of career stages (from PhD students to experts) and disciplines. This collaborative process, structured across five phases, ensured the glossary’s depth and comprehensiveness.ResultsThe glossary features over 300 terms categorized into six key domains: analysis, experimental design, hardware, neuroscience, mathematics, and physics. It also includes abbreviations, symbols, synonyms, references, alternative definitions, and figures where relevant.ConclusionsThe fNIRS glossary provides a community-sourced resource that facilitates education and effective scientific communication within the fNIRS community and related fields. By lowering barriers to learning and engaging with fNIRS, the glossary is poised to benefit a broad spectrum of researchers, including those with limited access to educational resources.

Every day we combine and switch between body-centered (egocentric) and object-centered (allocentric) spatial representations. Several studies so far have reported a greater difficulty to switch from an allocentric reference frame to an egocentric one than vice-versa. To clarify this effect, the present work measured the cognitive load underlying switching vs. non-switching processes between reference frames through cognitive pupillometry. Participants performed a custom-designed visuo-spatial memory task, while pupil dilation variations were measured with eye-tracking. After memorizing triads of objects, participants provided judgments of relative distance in non-switching (only-egocentric, only-allocentric) and switching (from-ego-to-allo, from-allo-to-ego) conditions. The results showed a larger pupil dilation in switching judgments from-allocentric-to-egocentric reference frames than from-egocentric-to-allocentric ones. Moreover, pupil evoked-responses were also larger in allocentric- than egocentric-based non-switching conditions. Overall, the results showed that, for both non-switching and switching visuo-spatial processes, starting from an allocentric-based representation elicits a higher cognitive load than starting from an egocentric-based one. Thus, the disproportional effort in visuo-spatial switching processes seems to be determined by the first reference frame adopted that, in turn, contaminates also the following one.

Pouring water from a bottle into a glass requires representing their relative spatial positions (spatial information) and knowing that such objects are found together, or one by one (temporal dynamics), in typical contexts, such as a kitchen (semantic information).While spatial information is encoded using egocentric (body-centered) or allocentric (object-centered) reference frames, semantic knowledge is organized in context frames, which help predict object–context associations. This study investigates whether daily-like semantic contexts and temporal dynamics affect egocentric and allocentric spatial representations. Participants were immersed in semantically meaningless (abstract) or meaningful (bathroom, kitchen) virtual environments. They memorized triads of objects presented either simultaneously (static condition) or sequentially (dynamic condition) and then provided egocentric or allocentric spatial judgments. Results revealed an improvement of allocentric accuracy in meaningful rather than meaningless environments, whereas no differences emerged for egocentric spatial judgments. Crucially, this semantic benefit for allocentric encoding emerged only in the dynamic condition, where spatial information had to be integrated over time. These findings show that semantic context selectively facilitates allocentric spatial representations, particularly when perceptual input unfolds dynamically. The results support the interaction between semantic and spatial memory to shape how we perceive the surrounding world.

Significance A shared understanding of terminology is essential for clear scientific communication and minimizing misconceptions. This is particularly challenging in rapidly expanding, interdisciplinary domains that utilize functional near-infrared spectroscopy (fNIRS), where researchers come from diverse backgrounds and apply their expertise in fields such as engineering, neuroscience, and psychology. Aim The fNIRS Glossary Project was established to develop a community-sourced glossary covering key fNIRS terms, including those related to the continuous-wave (CW), frequency-domain (FD) and time-domain (TD) NIRS techniques. Approach The glossary was collaboratively developed by a diverse group of 76 fNIRS researchers, representing a wide range of career stages (from PhD students to experts) and disciplines. This collaborative process, structured across five phases, ensured the glossary's depth and comprehensiveness. Results The glossary features over 300 terms categorized in six key domains: analysis, experimental design, hardware, neuroscience, mathematics, and physics (https://openfnirs.org/standards/fnirs-glossary-project). It also includes abbreviations, symbols, synonyms, references, alternative definitions, and figures where relevant. Conclusions The fNIRS glossary provides a community-sourced resource that facilitates education and effective scientific communication within the fNIRS community and related fields. By lowering barriers to learning and engaging with fNIRS, the glossary is poised to benefit a broad spectrum of researchers, including those with limited access to educational resources.