An in vivo bioelectronic tongue for sweetness detection using rat gustatory perception based on brain-computer interface

The detection of sweetness is of great significance due to flavor and health concerns. In this study, an in vivo bioelectronic tongue for sweetness detection is constructed using rat gustatory system and implantable microelectrode array. By recording extracellular potentials in “sweet hotspot” within rat gustatory cortex, sweetener-evoked response patterns are generated by neural decoding algorithms. The results show that sweetener stimulation can cause a significant increase in the power spectral density of the local field potentials signal at 50-80 Hz, and its dynamic response in the time domain can be used for identification and classification of sweetness. Meanwhile, quantitative study shows that power of response signal is dose-dependent and the detection range covers sugar contents of daily beverages. Comparisons with results of human taste panelists also confirm that this in vivo bioelectronic tongue can work across species and has the potential to mimic human taste and evaluate sweetness in practical applications.