Humor associated mirthful laughter increases the intensity of power spectral density (μV2) EEG gamma wave band frequency (31–40Hz) which is associated with neuronal synchronization, memory, recall, enhanced cognitive processing and other brain health benefits when compared to distress
Authors: Berk Lee , Lee Jinhyun , Mali Deeti , Lohman Everett , Bains Gurinder , Daher Noha , Bradburn Jessica , Mohite Ronak , Vijayan Nikita , Juneja Savleen , Shah Srishti , Shah Ankit , Shah Pankti 
Published: November 2023

Eustress and distress are complex processes that can differentially modulate positive or negative aspects of brain EEG frequencies and psychoneuroimmunological (PNI) mechanisms. The eustress of humor associated mirthful laughter (HAML) are related to fundamental aspects of human behavior. Some experiences are characterized by modulating brain, PNI mechanisms and behavior for positive health benefits. No known electroencephalographic (EEG) study has been conducted to differentiate Power Spectral Density μV2 (PSD) correlates across EEG frequency bins1–40Hz for comparison of eustress HAML and distress and which is the predominant frequency that may produce brain health benefits.

Purpose

The purpose of this study was to assess the PSD of all EEG frequencies (0–40Hz) to determine which was the most predominate frequency during HAML compared to distress.

Methods

In a cross‐over design each subject was randomly administered two 10 minute videos: HAML (America's Funniest Home Videos) and Stress (Movie ‐ Saving Private Ryan). EEG wave band activity was recorded from 9 scalp regions F3, Fz, F4, C3, Cz, C4, P3, POz, and P4 (10–20 System) using the EEG B‐Alert 10X System™ Carlsbad, CA).

Results

HAML compared to distress showed Beta Band Activity (13–30Hz) (βBA) (p=0.01) and Gamma Band Activity (γBA) (31–40HZ) (p=0.001) for PSD greatest for all 9 regions. With further specific non‐parametric analysis using the Friedman and the Wilcoxon Signed Rank Test we observed the within group effect for HAML that γBA was significantly greater than all other 6 frequencies p<0.001(See Bar Graph and Table).

Conclusions

HAML shows EEG PSD correlates of change for specific bandwidths but greatest for γBA across all measured cerebral cortex regions (synchrony). Previous research show PSD γBA is suitable for EEG‐based emotion classification of happiness versus sadness. Our EEG findings further suggest eustress HAML increases PSD γBA the greatest of all frequencies thus providing for enhance memory and recall, enhanced cognition processing (neuronal synchrony), sensory perception, and positive affect of mood state and happiness plus other peripheral related physiological health benefits.

Gamma compared to all frequencies

Delta x̄† (1–3Hz)
Delta: −0.12

Gamma x̄† (31–40Hz)
Gamma: 0.38

p‐value
p<0.001

X̄ difference
0.5

Theta Slow x̄† (3–5Hz)
Theta Slow: −0.10

Gamma x̄† [31–40Hz)
Gamma: 0.38

p‐value
p<0.001

x̄ difference
0.48

Theta Fast x̄† (5–7Hz)
Theta Fast: −0.08

Gamma x̄† (31–40Hz)
Gamma: 0.38

p‐value
p<0.001

x̄ difference
0.46

Alpha Slow x̄† (8–10Hz)
Alpha Slow: −0.03

Gamma x̄† (31–40Hz)
Gamma: 0.38

p‐value
p<0.001

x̄ difference
0.41

Alpha Fast x̄† (10–13Hz)
Alpha Fast: 0.00

Gamma x̄† (31–40Hz)
Gamma: 0.38

p‐value
p<0.001

x̄ difference
0.38

Beta x̄† (13–30Hz)
Beta: 0.20

Gamma x̄† (31–40Hz)
Gamma: 0.38

p‐value
p<0.001

x̄ difference
0.18

Z‐scored PSD μV2