k-Means clustering by using the calculated Z-scores from QEEG data of children with dyslexia

Abstract

Learning the subtype of dyslexia may help shorten the rehabilitation process and focus more on the relevant special education or diet for children with dyslexia. For this purpose, the resting-state eyes-open 2-min QEEG measurement data were collected from 112 children with dyslexia (84 male, 28 female) between 7 and 11 years old for 96 sessions per subject on average. The z-scores are calculated for each band power and each channel, and outliers are eliminated afterward. Using the k-Means clustering method, three different clusters are identified. Cluster 1 (19% of the cases) has positive z-scores for theta, alpha, beta-1, beta-2, and gamma-band powers in all channels. Cluster 2 (76% of the cases) has negative z-scores for theta, alpha, beta-1, beta-2, and gamma-band powers in all channels. Cluster 3 (5% of the cases) has positive z-scores for theta, alpha, beta-1, beta-2, and gamma-band powers at AF3, F3, FC5, and T7 channels and mostly negative z-scores for other channels. In Cluster 3, there is temporal disruption which is a typical description of dyslexia. In Cluster 1, there is a general brain inflammation as both slow and fast waves are detected in the same channels. In Cluster 2, there is a brain maturation delay and a mild inflammation. After Auto Train Brain training, most of the cases resemble more of Cluster 2, which may mean that inflammation is reduced and brain maturation delay comes up to the surface which might be the result of inflammation. Moreover, Cluster 2 center values at the posterior parts of the brain shift toward the mean values at these channels after 60 sessions. It means, Auto Train Brain training improves the posterior parts of the brain for children with dyslexia, which were the most relevant regions to be strengthened for dyslexia.

Keywords:

• Auto Train Brain
• clustering
• developmental dyslexia

Acknowledgments

We are especially grateful to the families who participated in this study; without their dedication and support, we may not have completed it.

Ethics approval and consent to participate

All the participants gave their informed consent after the experimental procedure was explained to them by guidelines set by the research ethics committee of Sabancı University, the protocol of the study was approved by the Ethics Committee of Yeditepe University and the clinical trial was registered to the Turkey Pharmaceuticals and Medical Devices Agency (Nbr: 71146310-511.06,2.11.2018).

Disclosure statement

The authors declare the following financial interests which may be considered as potential competing interests. Auto Train Brain has been developed at Sabancı University laboratories. This work has led to the formation of a company aimed to make Auto Train Brain available to users (www.autotrainbrain.com).

Data availability statement

The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.