Toward operational architectonics of consciousness: basic evidence from patients with severe cerebral injuries

Abstract

Although several studies propose that the integrity of neuronal assemblies may underlie a phenomenon referred to as awareness, none of the known studies have explicitly investigated dynamics and functional interactions among neuronal assemblies as a function of consciousness expression. In order to address this question, EEG operational architectonics analysis (Fingelkurts and Fingelkurts 2001, 2008) was conducted in patients in minimally conscious (MCS) and vegetative states (VS) to study the dynamics of neuronal assemblies and operational synchrony among them as a function of consciousness expression. We found that in minimally conscious patients and especially in vegetative patients neuronal assemblies got smaller, their life span shortened and they became highly unstable. Furthermore, we demonstrated that the extent/volume and strength of operational synchrony among neuronal assemblies was smallest or even absent in VS patients, intermediate in MCS patients, and highest in healthy fully conscious subjects. All findings were similarly observed in EEG alpha as well as beta1 and beta2 frequency oscillations. The presented results support the basic tenets of operational architectonics theory of brain-mind functioning and suggest that EEG operational architectonics analysis may provide an objective and accurate means of assessing signs of (un)consciousness in patients with severe brain injuries. Therefore, this methodological approach may complement the existing "gold standard" of behavioral assessment of this population of challenging patients and inform the diagnostic and treatment decision-making processes.

Dissociation of Vegetative and Minimally Conscious Patients Based on Brain Operational Architectonics

“…Additionally, patients in VS had a significantly decreased number and strength of functional connections between neuronal assemblies compared to patients in MCS, irrespective of brain damage etiology. Moreover, in the present study decreases and increases coincide precisely with our previous results, 68 where patients with different brain damage etiologies were intermixed (see Figure 1). …”

“…68,69 Therefore, this is a retrospective study, but it is original, since these EEG data had not yet been used for the evaluation of OA indexes of resting EEG as a function of brain damage etiologies; in previous studies the factor of etiology was not considered.…”

“…As in previous work, 68 comparison of the same segment attributes between different group conditions (considering each EEG electrode) was performed using Wilcoxon matched pairs t test.…”

“…At the same time, fluctuating (minimal) awareness in patients in MCS was paralleled by partial restoration of EEG operational architecture (increased size, life span, and stability of neuronal assemblies, together with an increased number and strength of functional connections among them; Figure 1), approaching the level found in healthy fully conscious participants. 68 In light of these results, it is reasonable to assume that EEG operational architecture can be useful for distinguishing patients in VS and MCS. In context of the present article, the previous study 68 had an important limitation: patients in both (VS and MCS) subgroups had mixed etiologies of brain damage.…”

Information Flow in the Brain: Ordered Sequences of Metastable States

“…In this context, the brain operates as a highly dynamic system where large metastable spatial-temporal patterns of stabilized activity (indexed as OMs) formed only for very brief episodes and then quickly dissipated allowing the brain (as a whole) to have more degrees of freedom to form new metastable OMs needed to execute newly immediately-emerged and ever-changing operations of different complexity [22]. This dynamic can be significantly altered during pharmacological influence, neurological or psychiatric pathology or as result of traumatic brain damage when consciousness (including self-awareness) is minimal or lost completely [73][74][75][76]. It may also be intentionally altered through mental training such as meditation [77,78].…”