title: An integrative model of auditory phantom perception: tinnitus as a unified percept of interacting separable subnetworks.
abstract: Tinnitus is a considered to be an auditory phantom phenomenon, a persistent conscious percept of a salient memory trace, externally attributed, in the absence of a sound source. It is perceived as a phenomenological unified coherent percept, binding multiple separable clinical characteristics, such as its loudness, the sidedness, the type (pure tone, noise), the associated distress and so on. A theoretical pathophysiological framework capable of explaining all these aspects in one model is highly needed. The model must incorporate both the deafferentation based neurophysiological models and the dysfunctional noise canceling model, and propose a 'tinnitus core' subnetwork. The tinnitus core can be defined as the minimal set of brain areas that needs to be jointly activated (=subnetwork) for tinnitus to be consciously perceived, devoid of its affective components. The brain areas involved in the other separable characteristics of tinnitus can be retrieved by studies on spontaneous resting state magnetic and electrical activity in people with tinnitus, evaluated for the specific aspect investigated and controlled for other factors. By combining these functional imaging studies with neuromodulation techniques some of the correlations are turned into causal relationships. Thereof, a heuristic pathophysiological framework is constructed, integrating the tinnitus perceptual core with the other tinnitus related aspects. This phenomenological unified percept of tinnitus can be considered an emergent property of multiple, parallel, dynamically changing and partially overlapping subnetworks, each with a specific spontaneous oscillatory pattern and functional connectivity signature. Communication between these different subnetworks is proposed to occur at hubs, brain areas that are involved in multiple subnetworks simultaneously. These hubs can take part in each separable subnetwork at different frequencies. Communication between the subnetworks is proposed to occur at discrete oscillatory frequencies. As such, the brain uses multiple nonspecific networks in parallel, each with their own oscillatory signature, that adapt to the context to construct a unified percept possibly by synchronized activation integrated at hubs at discrete oscillatory frequencies.
authors.affiliation: TRI Neurostimulation Workgroup; Unit of Neurosurgery, Department of Surgical Sciences, Dunedin School of Medicine, University of Otago, New Zealand. Electronic address: dirk.deridder@otago.ac.nz.
authors.forename: Dirk
authors.initials: D
authors.lastname: De Ridder
authors.affiliation: TRI Neurostimulation Workgroup; Department of Translational Neuroscience, University Antwerp, Belgium.
authors.forename: Sven
authors.initials: S
authors.lastname: Vanneste
authors.affiliation: TRI Neurostimulation Workgroup; Center for Mind/Brain Sciences (CIMeC), University of Trento, Italy.
authors.forename: Nathan
authors.initials: N
authors.lastname: Weisz
authors.affiliation: TRI Neurostimulation Workgroup; Service ORL et Chirurgie Cervico-faciale, Hôpital Européen G. Pompidou, Paris, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Londero
authors.affiliation: TRI Neurostimulation Workgroup; Clinical and Biological Psychology, Institute of Psychology and Education, University of Ulm, Germany.
authors.forename: Winnie
authors.initials: W
authors.lastname: Schlee
authors.affiliation: TRI Neurostimulation Workgroup; Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, CONICET and Departamento de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Argentina.
authors.forename: Ana Belen
authors.initials: AB
authors.lastname: Elgoyhen
authors.affiliation: TRI Neurostimulation Workgroup; Interdisciplinary Tinnitus Clinic, Department of Psychiatry and Psychotherapy, University of Regensburg, Germany.
authors.forename: Berthold
authors.initials: B
authors.lastname: Langguth
mesh_terms: D001307:Auditory Perception / Q000502:physiology*; D001921:Brain; D004594:Electrophysiology; D006801:Humans; D008959:Models, Neurological; D010591:Phantom Limb / Q000523:psychology*; D014012:Tinnitus / Q000473:pathology* / Q000503:physiopathology*
keywords: Deafferentation; EEG; MEG; Neuromodulation; Phantom sound; TMS; Tinnitus; tDCS