[Abstract] Dark chocolate (70% organic cacao) increases acute and chronic EEG power spectral density (μV2) response of gamma frequency (25–40 Hz) for brain health: enhancement of neuroplasticity, neural synchrony, cognitive processing, learning, memory, recall, and mindfulness meditation

Abstract

Cacao or dark chocolate is a major source of flavonoids. Flavonoids are extremely potent antioxidants and anti-inflammatory agents, with known mechanisms beneficial for cardiovascular health. However, the correlates of neuroelectric activity that initiate the mechanisms of cacao’s effects on brain neurocognition, synchronization, memory, recall, mood and behavior are not well known. Studies have shown that absorbed cacao flavonoids penetrate and accumulate in brain hippocampal regions involved in learning and memory. However, neurological initiation and modulatory control from acute and chronic exposure of cacao flavanoids (via consumption) on intensity of kinetic response of brain frequency and specifically beneficial gamma frequency (25–40 Hz), has not been studied.

Purpose

Therefore, the purpose of this study was to assess the Electroencephalography (EEG) response to consuming 48 g of dark chocolate (70% cacao) after an acute period of time (30 mins) and after a chronic period of time (120 mins), on modulating brain frequencies 0–40 Hz; specifically beneficial gamma frequency (25–40 Hz).

Methods

Dark chocolate bars, made from Tanzania organic cocoa beans consisting 70% cacao and 30% organic cane sugar, were used in this study (Parliament Chocolate, Redlands, CA). EEG wave bandwidth activity was recorded from 9 cerebral cortical scalp locations F3, Fz, F4, C3, Cz, C4, P3, Pz, and P4 using the EEG B-Alert 10X System™ (Advanced Brain Monitoring, Carlsbad, CA). Each of 5 healthy subjects, age 22–40, consumed 48 g of the dark chocolate after the baseline EEG acquisition. At an acute period of time (30 mins) and chronic period of time (120 mins) EEG was recorded for two mins. From each of the 5 subjects and summated for the respective time points. Power Spectral Density uV 2  (PSD) were Z-scored for the two time points using the reference pretest resting EEG baseline..

Results

Z-scores were graphed for both acute and chronic time periods across 0–40 Hz ( Fig. 1 ). The most significant outcome observed showed PSD γBA was quantitatively greatest of all frequencies in the study (p<0.01). In  Fig, 2 , using “heatmaps”, we show qualitative responses for extent and intensity (PSD) of the cacao on the cerebral cortical brain for: baseline (Task 1 – after 8 hr n.p.o., and no cacao) for both acute and chronic time periods (Task 2 – 30 mins post consumption and Task 3 – 120 mins post consumption, respectively). The acute time period (Task 2) clearly shows the entire cerebral cortical region is modulated to varying degrees of PSD increase in γBA, with the largest increase in regions C4/P4/PZ/P3, while the chronic time period (Task 3) shows the frontal left side returning towards baseline, but still has residual γBA in C4/P4/Pz regions.

Conclusion

This study provides quantitative and qualitative evidence that EEG γBA is enhanced by consumption of 48 g 70% cacao and shows a significant acute effect at 30 mins post consumption to all cerebral cortical regions, and a residual γBA PSD response at 120 mins., primarily to brain EEG regions C4/P4/Pz. We suggest that 48 g 70% cacao consumption with a concentration of antioxidant activity of 52,000 umoles TE/100 g, is associated with subsequent γBA increase in the cerebral cortical brain. We suggest that this superfood of 70% cacao (organic cocoa beans from Tanzannia) enhances neuroplasticity for behavioral and brain health benefits. Further research is in progress to elaborate the mechanisms that may be involved in the cause/effect brain-behavior relationship.