The following is a summary of “Why Does Tardive Dyskinesia Have Oro-facial Predominance? A Network Analysis” published in the January 2023 issue of Psychiatry by Szalisznyó et al.
Tardive dyskinesia is an involuntary hyperkinetic disorder that typically manifests in elderly patients following prolonged administration of antipsychotic medications. The aforementioned dyskinesias are predominantly irreversible and commonly manifest in the tongue, cheeks, mandible, perioral area, and other facial regions. In this theoretical inquiry, we have asked why tardive dyskinesia frequently exhibits orofacial preponderance. What could be the underlying neural architecture that contributes to this inclination? The analysis of the network structure of the cortico-striato-thalamo-cortical system at a high level indicates the presence of a bottleneck in connectivity. In addition, the substantia nigra pars reticulata (SNr) exhibits a lower count of walks of varying lengths to other vertices and returning cycles, suggesting a heightened vulnerability to damage for this particular node within the network.
An examination was conducted on the published data derived from a recent histological study of high-resolution cortico-striato-thalamo-cortical networks in rodents. Upon conducting a finer network partitioning and adjacency matrices analysis, it has been observed that the SNr exhibits a heterogeneous connectivity structure. Additionally, it has been noted that the number of local walks originating from nodes close to orofacial neural representation is elevated, suggesting the presence of potential early compensatory escape routes. However, in cases of significant damage to the SNr, the compensatory mechanisms of the larger circuit may become restricted. The significance of this field of study lies in its potential for further investigation, as pinpointing critical susceptible anatomical components could lead to more precise therapeutic interventions.
Source: link.springer.com/article/10.1007/s10548-022-00931-y
