Masticationpedia

Complex Systems Abstract

Complex Systems

Masticationpedia
Masticationpedia
Article by: Gianni Frisardi

Abstract
This chapter introduces the concept of Connectivity as a key interpretive lens for understanding Complex Systems, and clarifies why the term—although widely used across disciplines—becomes fragile when treated as universally transferable without constraints. Connectivity is not a generic synonym for “connection”: it describes how distinct units exchange information, how that flow organizes into stable or unstable architectures, and how such architectures generate properties that cannot be reduced to single elements taken in isolation. To avoid an imprecise use of the term, the chapter establishes four methodological steps: (1) defining the fundamental unit of connectivity (node, subsystem, function, signal); (2) clearly separating structural connectivity (anatomical, physical, topological) from functional connectivity (dynamic, operational, context-dependent); (3) explaining the meaning of emergent behavior, i.e., global outcomes that are not predictable from a simple sum of parts; (4) proposing criteria by which connectivity can be measured, avoiding the confusion between narrative descriptions and verifiable parameters.

This framework is then applied to the masticatory function, traditionally interpreted as a peripheral activity limited to chewing and phonation, and therefore approached through a mainly reductionist clinical model: diagnosis and rehabilitation focused on the maxillae, occlusal relationships, and tests that describe movements or muscle activation without interrogating the system as a whole. The chapter argues instead that mastication should be treated as a complex system in the full sense, because it interacts with a multitude of centers and circuits within the Central Nervous System, including structures that are functionally distant from the stomatognathic periphery. In this view, the masticatory “organ” is not defined by mechanics alone: it is a node within a broader neurophysiological network, where function emerges from multiple, non-linear interactions that are often stochastic.

In biological systems, the clinically relevant output is not always directly readable: it may appear as Emergent Behavior, produced by the interaction of heterogeneous constituents across time and space. For this reason, it is insufficient to analyze a single element (a muscle, a joint, an EMG trace) to understand the system’s state. A conceptual shift is required: the masticatory function must be treated as an indeterministic network that can be “interrogated” through external stimulation, and interpreted through evoked responses capable of revealing the internal organization of the network.

To support this approach, the chapter recalls evidence of interactions between the trigeminal system and other systems, including effects on perfusion and neurophysiological connections with vestibular pathways, showing that mastication is intertwined with postural, sensory, and central regulation. The consequence is a need for interdisciplinary diagnostic models, in which neurophysiological data—such as those obtained through trigeminal evoked potentials and related methods—become tools to translate complexity into more robust clinical criteria. In this sense, the expression “Neuro-Gnathological Functions” is introduced, marking the transition from a mechanistic gnathology to an integrated functional analysis, and setting the conceptual base for subsequent neurophysiological and clinical chapters.

Figure: EMG trace representing a vestibular evoked potential recorded on the masseter muscles. Note that p11 and n21 indicate the potential latency at 11 and 21 ms from the acoustic stimulus
Figure: EMG trace representing a vestibular evoked potential recorded on the masseter muscles. Note that p11 and n21 indicate the potential latency at 11 and 21 ms from the acoustic stimulus

🧠 Three guiding questions (with essential answers)

1️⃣ Why is the concept of connectivity insufficient if treated as a generic notion of “connection” in complex systems? — Because connectivity does not simply describe the presence of links between elements, but defines how information flows between specific units, how those flows organize into functional architectures, and how such architectures generate emergent properties that cannot be inferred from isolated components.

2️⃣ Why is a reductionist clinical approach inadequate for interpreting the masticatory function? — Because mastication operates as a complex and stochastic system interacting with multiple central nervous system structures, and its clinically relevant behavior emerges from non-linear, system-level interactions rather than from isolated mechanical or local anatomical parameters.

3️⃣ What methodological shift is required to correctly diagnose complex biological systems such as mastication? — A shift from descriptive and static measurements toward an integrated system logic that distinguishes structural from functional connectivity, investigates emergent behavior, and uses external stimulation with evoked responses to reveal the internal organization of the neurophysiological network.

🔒 Access to the full chapter
👤 Approved users
If you already have an approved account, click on your profile icon and return to the Book Index to read the complete chapter.
🔑 New readers
To access the full content, you must sign in via LinkedIn and request approval.

Bibliography & references

  • Viggiano A, Manara R, Conforti R, Paccone A, Secondulfo C, Lorusso L, Sbordone L, Di Salle F, Monda M, Tedeschi G, Esposito F, «Mastication induces long-term increases in blood perfusion of the trigeminal principal nucleus», in Neuroscience, 2015».
    PMID:26477983
    DOI:10.1016/j.neuroscience.2015.10.017 
  • Florio T, Capozzo A, Cellini R, Pizzuti G, Staderini EM, Scarnati E, «Unilateral lesions of the pedunculopontine nucleus do not alleviate subthalamic nucleus-mediated anticipatory responding in a delayed sensorimotor task in the rat», in Behav Brain Res, 2001».
    PMID:11704255
    DOI:10.1016/S0166-4328(01)00248-0 
  • Kondo K, Niino M, Shido K, «Dementia: A case-control study of Alzheimer's disease in Japan – significance of life-styles», 1994».
    PMID:7866485
    DOI:10.1159/000106741 
  • Shirasu M, Takahashi T, Yamamoto T, Itoh K, Sato S, Nakamura H, «Direct projections from the central amygdaloid nucleus to the mesencephalic trigeminal nucleus in rats», in Brain Res, 2011».
    PMID:21640334
    DOI:10.1016/j.brainres.2011.05.026 
Estratto da "https://staging.masticationpedia.org/index.php?title=Complex_Systems_Abstract&oldid=5685"