Low versus high cacao anti‐oxidant consumption effects on power spectral density (μV2) EEG brain frequencies (0–40Hz) and significance of sensory olfaction and taste deprivation of cacao to decrease the response of power spectral density for gamma frequency
Authors: Berk Lee , Lee Jinhyun , Mali Deeti , Lohman Everett , Bains Gurinder , Daher Noha , Bradburn Jessica , Mohite Ronak , Juneja Savleen , Vijayan Nikita , Shah Srishti , Shah Ankit , Shah Pankti 
Published: November 2023

Cacao (dark chocolate) are a major source of flavonoids. Cacao flavonoids are potent antioxidants and anti‐inflammatory components, with known mechanisms beneficial to cardiovascular health. However, the correlates of neuroelectric activities that initiate the mechanisms of cocoa's beneficial effects on brain neurocognition, synchronization, memory, recall, mood and behavior are unknown. Studies have shown that absorbed cocoa flavonoids penetrate and accumulate in brain hippocampal regions involved in learning and memory. Neurobiological correlates of cocoa flavonoids cascade the expression of neuroprotective and neuromodulatory proteins that promote neurogenesis, neuronal function, brain connectivity, blood‐flow improvement and angiogenesis in brain and sensory systems. However, neuroelectric activity initiation and modulatory control of acute action from cacao flavanoids on brain state has remained unknown.

Purpose

The purpose of this study is to provide evidence for cacao initiation of brain state frequency modulation and differentiation (0–40Hz) via electroencephalography (EEG) for: 1) Subjects who consumed “low concentrations” of cacao anti‐oxidant activity (1,840 μmoles TE/100g) to achieve satiation versus subjects who consumed “high concentrations” of cacao anti‐oxidant activity (17,480 μmoles TE/100g) for satiation and; 2) Compare a subject lacking a sensory olfaction and taste versus a normal subject in the study for differentiation of EEG response.

Methods

Assessment of EEG Power Spectral Density μV2 (PSD) of subjects during a sequence of cacao cognitive and sensory awareness tasks ranging from cognition of past chocolate experience, imaging currently eating chocolate, visualization of real chocolate, olfaction of chocolate, tasting chocolate but not swallowing, and finally consumption of cacao to satiation (70% cacao bar with 30% organic cane sugar (coco beans from Dominican Republic: Oko Caribe), Parliament Chocolate, Redlands, CA). Using the 10–20 System EEG wave band activity was recorded from 9 cerebral cortical scalp regions F3, Fz, F4, C3, Cz, C4, P3, Pz, and P4 using the EEG B‐Alert 10X System™, Carlsbad, CA. Second by second nine bandwidth (BW) for each subject was recorded. The PSD BW values were referenced to the eyes closed baseline task and Z‐scored.

Results

Z‐scores were analyzed and graphed for each task and BW across 0–40 Hz. We compared the lowest and highest cacao consumption subjects and observed all band frequencies not statistically significant except for beta and gamma (γBA) which were higher in the low consumption subject (p<0.05) (See Figure 1). In addition, we studied a subject olfaction & taste deprived but yet “loved” cacao. When compared with a normal subject who “loved” cacao, PSD for all BW was observed to be not significantly different except for γBA, which was significantly lower in the sensory deprived subject (p<0.01) (See Figure 2).

Conclusion

This study provides objective evidence that EEG PSD frequencies can be differentially modulated by varying the anti‐oxidant dose concentrations of cacao and, in addition, deprivation of the senses of olfaction and taste appears to diminishes γBA. It should be noted that the differences observed are at the higher end of the frequency band. Further research is needed to understand whether these are significance findings that may have health and clinical applications.

Subject LoAoA v/s Subject HiAoA Comparison

Delta X̄† ± SEM (1–3Hz)
LoAoA: 1.10±0.47

Delta X̄† ± SEM (1–3Hz)
HiAoA: 0.89±0.32

p‐value
0.72*

X̄ difference
0.21

Theta X̄† ± SEM (3–7Hz)
LoAoA: 0.89±0.35

Theta X̄† ± SEM (3–7Hz)
HiAoA: 0.57±0.04

p‐value
0.41*

X̄ difference
0.32

Alpha X̄† ± SEM (8–13Hz)
LoAoA: 0.23±0.35

Alpha X̄† ± SEM (8–13Hz)
HiAoA: −0.02±0.30

p‐value
0.26‡

X̄ difference
0.25

Beta X̄† ± SEM (13–30Hz)
LoAoA: 2.65±0.76

Beta X̄† ± SEM (13–30Hz)
HiAoA: 0.97±0.12

p‐value
0.01‡

X̄ difference
1.68

Gamma X̄† ± SEM (31–40Hz)
LoAoA: 4.70±0.95

Gamma X̄† ± SEM (31–40Hz)
HiAoA: 2.28±0.41

p‐value
0.03‡

X̄ difference
2.42

Z‐scored PSD (μV2)

Independent t‐test (parametric)

Mann‐Whitney test (non‐parametric)

LoAoA = Low Antioxidant Activity (2 pieces = 1,840 μmoles TE/100g)

HiAoA = High Antioxidant Activity (19 pieces = 17,480 μmoles TE/100g)

Dominican Republic: Oko Caribe beans antioxidant activity is 46.000 μmoles TE/100g

Subject SDS v/s NORM Comparison

Delta X̄† ± SEM (1–3Hz)
SDS: 1.09±0.50

Delta X̄† ± SEM (1–3Hz)
NORM: 0.26±0.05

p‐value
0.16*

X̄ difference
0.83

Theta X̄† ± SEM (3–7Hz)
SDS: 0.64±0.50

Theta X̄† ± SEM (3–7Hz)
NORM: 0.29±0.07

p‐value
0.51*

X̄ difference
0.35

Alpha X̄† ± SEM (8–13Hz)
SDS: −0.36±0.40

Alpha X̄† ± SEM (8–13Hz)
NORM: −0.35±0.22

p‐value
0.29*

X̄ difference
0.01

Beta X̄† ± SEM (13–30Hz)
SDS: 0.92±0.53

Beta X̄† ± SEM (13–30Hz)
NORM: 0.29±0.03

p‐value
0.98*

X̄ difference
0.63

Gamma X̄† ± SEM (31–40Hz)
SDS: 0.96±0.48

Gamma X̄† ± SEM (31–40Hz)
NORM: 4.51±0.10

p‐value
<0.01*

X̄ difference
3.55

Z‐scored PSD μV2

Independent t‐test (Note: All PSD for each Task for each subject was averaged and statistically analyzed.)

SDS= Sensory Deprived Subject (Lacking taste and olfaction)

NORM‐ Normal Subject representative of the normal cohort studied.