Neural Mechanisms of Organism-Dependent Affordances: The XPLR-XPLT Movement Spectrum

Abstract Affordances face definitional chaos. Ecological psychologists disagree about their ontological status (dispositional properties vs. organism-environment relations) and about their processing mechanisms (direct perception vs. representational inference). The only characteristics researchers agree on are that affordances are organism-dependent and action-related, yet actions escape definitions across ecological psychology, philosophy, and neuroscience. After reviewing definitions of actions across these three fields, this article operationalises actions as observable movements varying systematically from exploratory (XPLR) to exploitative (XPLT). Behavioural evidence shows that movements become automated across training, with decreasing reaction times and reduced variability. Neural evidence reveals cortical and subcortical networks that correlate with the automation of movements with training. The movement spectrum accommodates both dispositional and relational ontologies by specifying how organism-dependence operates through neural reorganisation. Orthogonally, the XPLR-XPLT spectrum applied to movements at immediate timescales addresses the sensorimotor perception-movement loop. Whether this is direct or representational remains an open question. This work provides a mechanistic specification for organism-dependence compatible with competing camps.