[The reticular paradigm of cortical memory]

Recent advances in cognitive neuroscience oblige us to change radically the traditional model of representation of memory in the cerebral cortex. The old -modular- model postulates a separate area for each form of memory (working memory, episodic memory, visual memory, auditory memory, tactile memory, etc.). In the new -reticular- paradigm, memories and items of knowledge are made of widely distributed networks of neuron populations synaptically connected by experience.

Memory networks overlap and interact profusely; a neuron or group of neurons can be part of many networks, thus many memories or items of knowledge. After birth and throughout life, each new experience is etched in the form of those networks or cognits by synaptic associative processes that course from area to area along phylogenetic, ontogenetic, and connective gradients, from sensory and motor areas into associative areas. By self-organization, new cognits distribute themselves within two cortical hierarchies with a sensory and motor base, respectively. The perceptual hierarchy, in posterior cortex, houses cognits defined by sensory parameters in sensory areas and perceptual memories in associative areas. The executive hierarchy, on the other hand, represents concrete movements in frontal motor areas and more complex actions (e.g., plans) in prefrontal cortex.

The reticular memory paradigm has important implications with regard to the cognitive development of the individual, cortical clinical syndromes, and cognitive rehabilitation.