Higuchi fractal dimension is a unique indicator of working memory content represented in spiking activity of visual neurons in extrastriate cortex

• Published in: Mathematical biosciences and engineering : MBE Vol. 20; no. 2; pp. 3749 - 3767
• Main Authors: Vivekanandhan, Gayathri, Mehrabbeik, Mahtab, Rajagopal, Karthikeyan, Jafari, Sajad, Lomber, Stephen G, Merrikhi, Yaser
• Format: Journal Article
• Language: English
• Published: United States AIMS Press 01-01-2023
• Subjects: Brain; dimensionality; Fractals; higuchi fractal dimension; Memory, Short-Term - physiology; middle temporal cortex; Neurons - physiology; spiking activity; Visual Cortex - physiology; working memory; Higuchi fractal dimension; spiking activity; dimensionality; middle temporal cortex; working memory
• ISSN: 1551-0018; 1551-0018
• DOI: 10.3934/mbe.2023176

Working memory has been identified as a top-down modulation of the average spiking activity in different brain parts. However, such modification has not yet been reported in the middle temporal (MT) cortex. A recent study showed that the dimensionality of the spiking activity of MT neurons increases after deployment of spatial working memory. This study is devoted to analyzing the ability of nonlinear and classical features to capture the content of the working memory from the spiking activity of MT neurons. The results suggest that only the Higuchi fractal dimension can be considered as a unique indicator of working memory while the Margaos-Sun fractal dimension, Shannon entropy, corrected conditional entropy, and skewness are perhaps indicators of other cognitive factors such as vigilance, awareness, and arousal as well as working memory.