Metastability and Eye Movements: A Dynamical‑Systems Interpretation

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  1. Why metastability is a natural language for gaze behavior The idea that perception, attention, and neural activity evolve through transiently stable states has deep roots in cognitive science and neuroscience. Concepts such as attractors , basins , noise‑induced transitions , and escape times appear in work on perceptual switching, decision‑making, and neural population dynamics (Kelso, 1995; Rabinovich et al., 2008; Deco & Jirsa, 2012). Eye movements, especially the alternation between fixations and saccades ,   fit remarkably well into this metastable picture. The Freidlin–Wentzell theory of rare events (Freidlin & Wentzell, 2012) provides a rigorous mathematical language for these intuitions. 2. Fixations as metastable states  Consider the gaze position X t as the state of a stochastic dynamical system. During a fixation the  gaze remains confined to a small region, microsaccades and noise generate small fluctuations, and the gaze tends to return...
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A Continuous Semantic Space Describes the Representation of Thousands of Object and Action Categories across the Human Brain

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"Humans can recognize thousands of categories. Given the limited size of the human brain, it seems unreasonable to expect that every category is represented in a distinct brain area,”

says first author Alex Huth, a graduate student working in Dr. Jack Gallant’s laboratory at the University of California, Berkeley.

In a video diplayed at the web page of NEURON [link to the  article], the author reports how 
objects and action categories are organized within the brain according to a continuous  semantic space throughout the cortical surface.


Dr. A.P. Masucci (Research fellow at the Centre for Advanced Spatial Analysis CASA, University College of London.) defines [here] the semantic space as: 

 "the space of meaning, where the dynamics of meaning keep place. Where is it? It is in our heads!! Language is a collective phenomena and it resides in all our heads. As a natural phenomena language follows its natural laws and self-organises in structures and hierarchies."



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