Octopus sentience: Three criteria

Analyzing octopus movements using three-dimensional reconstruction.

Octopus arms, as well as other muscular hydrostats, are characterized by a very large number of degrees of freedom and a rich motion repertoire. Over the years, several attempts have been made to elucidate the interplay between the biomechanics of these organs and their control systems. Recent developments in electrophysiological recordings from both the arms and brains of behaving octopuses ma...

Sentience Everywhere

Philosophical understandings of consciousness divide into emergentist positions (when the universe is sufficiently organized and complex it gives rise to consciousness) vs. panpsychism (consciousness pervades the universe). A leading emergentist position derives from autopoietic theory of Maturana and Varela: to be alive is to have cognition, one component of which is sentience. Here, reflectin...

A Theory of Sentience

Distribution of three retinal proteins in developing octopus photoreceptors.

The expression of proteins unique to plasma membrane domains of developing photoreceptors is used as a marker for retinal differentiation in vertebrates. Invertebrate photoreceptors are also compartmentalized, but little information is available on the development of these compartments or the expression of retinal proteins specific to these cellular regions. Using routine electron microscopy te...

Sentience and Pain in Invertebrates