Cinematic Operation of the Cerebral Cortex Interpreted via Critical Transitions in Self-Organized Dynamic Systems

Abstract

Measurements of local field potentials over the cortical surface and the scalp of animals and human subjects reveal intermittent bursts of beta and gamma oscillations. During the bursts, narrow-band metastable amplitude modulation (AM) patters emerge for a fraction of a second and ultimately dissolve to the broad-band random background activity. The burst process depends on previously learnt conditioned stimuli (CS), thus different AM patterns may emerge in response to different CS. This observation leads to our cinematic theory of cognition when perception happens in discrete steps manifested in the sequence of AM patterns. Our article summarizes findings in the past decades on experimental evidence of cinematic theory of cognition and relevant mathematical models. We treat cortices as dissipative systems that self-organize themselves near a critical level of activity that is a non-equilibrium metastable state. Criticality is arguably a key aspect of brains in their rapid adaptation, reconfiguration, high storage capacity, and sensitive response to external stimuli. Self-organized criticality (SOC) became an important concept to describe neural systems. We argue that transitions from one AM pattern to the other require the concept of phase transitions, extending beyond the dynamics described by SOC. We employ random graph theory (RGT) and percolation dynamics as fundamental mathematical approaches to model fluctuations in the cortical tissue. Our results indicate that perceptions are formed through a phase transition from a disorganized (high entropy) to a well-organized (low entropy) state, which explains the swiftness of the emergence of the perceptual experience in response to learned stimuli.

Nondual Awareness: Consciousness-as-such as non-representational reflexivity

“…Neural activity hierarchically organized via cross-frequency coupling, at theta-gamma or alpha-gamma bands has been proposed as signature of thalamo-cortical or hippocampal-cortical integration . Only one global workspace can operate at any given time, broadcasting one unified content, at the rate of approximately ten such broadcasts per second, that is in alpha range, further supporting the idea that the thalamocortical alpha binds contents (Kozma and Freeman, 2017). The integration of information within the global workspace that makes contents conscious also involves progressively increased conceptual abstraction, and binding by semantic schemas (Ricard and Singer, 2017).…”

Is conscious perception a series of discrete temporal frames?

“…An analogy is sometimes taken with film projection, originally by and , and by others since, including Craig (2009a), Freeman (2006), Hogendoorn (2016), Kozma and Freeman (2017), McComas and Cupido (1999), and Pockett, Brennan, Bold, and Holmes (2011). In this analogy, the frame of conscious perception is equivalent to a single frame of a film in the gate of the projector, and the subjective fluency of conscious perception is equivalent to the continuity of the film as projected on the screen.…”

“…And there is no proof that any oscillation, whether endogenous or stimulus-triggered, goes on everywhere and all the time in the waking state. The oscillations observed by Pockett et al (2011) and by Freeman and colleagues(Kozma & Freeman, 2017) may go on all the time and may be specific to the waking state, but it has not been established that they are connected with conscious perception, and they could relate to some function outside of conscious perception. There could be local, transient discrete frames associated with particular processes or functions, although again there is no clear evidence for such a thing.…”

“…Finally, if attentive processing does proceed in oscillations, this does not entail that conscious perception does the same. Percepts may be maintained continuously but modified periodically (and locally), and it is not clear that modifications of different perceptual features are temporally co-ordinated.3.2: The cinematic theory of cognitionThe cinematic theory of cognition was developed in several papers by Freeman and colleagues (principallyFreeman, 2004Freeman, , 2006Kozma & Freeman, 2017). Here I shall focus mainly on the most recent version, byKozma and Freeman (2017).…”

“…Percepts may be maintained continuously but modified periodically (and locally), and it is not clear that modifications of different perceptual features are temporally co-ordinated.3.2: The cinematic theory of cognitionThe cinematic theory of cognition was developed in several papers by Freeman and colleagues (principallyFreeman, 2004Freeman, , 2006Kozma & Freeman, 2017). Here I shall focus mainly on the most recent version, byKozma and Freeman (2017). The basis for the theory is the observation of large-scale co-ordination in cortical activity, manifested as cyclical periods of high amplitude (about 100 -200 ms in duration) separated by brief episodes (~20 ms) of low analytic power, called null spikes.…”