Characterizing the Cannabis Experience of the Surreal High Sun Mint Lime Fizz Beverage Using Cognalyzer® EEG

Published: August 11, 2023

Author: Dr. Dan Bosnyak, Upmanyu Sharma, Israel Gasperin

The cannabis industry has witnessed a significant investment in the development of products that offer unique cannabis experiences. These products are crafted by combining various cannabinoids, such as THC, CBD, CBN, CBG, CBC, THCA, among others, with a diverse array of non-cannabinoid ingredients like terpenes, sugar, chamomile, black tea or natural/artificial ingredients/flavours. The specific combination of cannabinoids and ingredients is carefully tailored to provide distinct cannabis experiences to consumers.

Furthermore, advanced drug delivery methods are employed to infuse cannabinoids into these products, aiming to create fast-acting and potent effects or slow but long-lasting experiences. This implies that two products with the same THC content (for instance, 10mg) can yield significantly different cannabis experiences based on the infusion techniques and the interactions between cannabinoids and other ingredients.

Consequently, it’s crucial to acknowledge that generalizing the potential effects of cannabis products solely based on the amounts of THC and/or other cannabinoids can be inaccurate and unreliable. It’s essential to scientifically characterize cannabis effects at a product level rather than a cannabinoid level to ensure accurate and reliable descriptions of the potential effects of legal products.

In light of this, in 2021 Zentrela started the world’s largest cannabis effect study with over 750 study participations with consumers including legal cannabis-infused beverages, edibles, pre-rolls and vapes. The primary objective of our research was to scientifically characterize the unique cannabis experience associated with these products. To achieve this, we employed a unique set of research tools, including electroencephalography (EEG), electrocardiography (ECG), psychological tests and cannabis effect questionnaires. These tools, used in a scientific, controlled and supervised data collection protocol, called CUSIC™, allowed us to delve into the distinctive cannabis experience created by the consumed product.

Herein, Zentrela scientifically characterized the unique cannabis experience created by the SURREAL High Sun Mint Lime Fizz beverage in study subjects. The SURREAL High Sun Mint Lime Fizz beverage contains 10mg of THC, 0mg of CBD, 10mg of CBG, and various non-cannabinoid ingredients such as 4g of sugar and lime juice concentrate, among others.

Through the execution of this study, Zentrela determined the onset time and maximum potency of the psychoactive effects induced by this specific product. Additionally, we quantified significant mood changes potentially associated with the consumption of this beverage.


This study was conducted with 21 study subjects who consumed the SURREAL High Sun Mint Lime Fizz beverage. Zentrela’s non-invasive portable EEG technology,  were used to record consumer EEG data from eight different regions of the brain (right and left sides of the frontal, temporal, parietal and occipital lobes).

The standardized process of collecting EEG data (called the ‘EEG Test’) consists of approximately two-minute-long recordings depending on the quality and integrity of the EEG data that is being recorded. Internal and external noise is ignored. Two EEG Tests were administered before product consumption to calibrate the Cognalyzer® AI solution and seven more EEG tests were administered after five, 10, 15, 20, 25, 30, 45, 60 and 120 mins product consumption.

Cognalyzer EEG (brainwave) analysis was used to convert EEG Tests into THC psychoactive effect levels (PEL) in a standardized scale from 0% to 100%. Learn more about it in the following section. The cubic spline interpolation method was used to accurately characterize PELs minute by minute post product consumption and per participant/visit. Then, the PELs of all the beverage consumers were aggregated.

Statistical analysis was conducted to determine the higher and lower bounds of the aggregated PELs using >90% confidence intervals. The onset time interval of the beverage psychoactive effect curve was determined by getting the time point of the first aggregated PEL above 5% and the time point of the first aggregated PEL above 15% when their lower bound of the confidence interval is above 90%.

The maximum potency and the time of this peak per product was determined by finding the maximum PEL of each curve and its time point.

The mood of the participant was assessed by completion of the Brunel Mood Scale (BRUMS; Terry et al., 1999, 2003). This 24-item questionnaire of simple mood descriptors such as angry, nervous, unhappy and refreshed is answered by “selecting which option best describes how you feel right now”, in response to 24 items such as “panicky” with the options being “not at all”, “a little”, “moderately”, “quite a lot” or “extremely” which is in turn quantified as a rating on a scale of 0-5.

The items are scored on six subscales: anger, confusion, depression, fatigue, tension and vigour. Subdividing moods into these six subscales has been an accepted procedure in the psychological literature for more than 20 years.  For ease of understanding we have characterized the endpoints of these subscales according to the following descriptors:

  1. Anxiety — Serenity (tension) 
  2. Confused — Lucid (confusion) 
  3. Angry — Peaceful (anger) 
  4. Unhappiness — Happiness (sad) 
  5. Alert — Relaxed (vigour)
  6. Fatigued — Refreshed (fatigue)

After measuring the initial mood profile of a participant before consuming the product, we use this information as a baseline and then calculate mood changes that occur from this baseline, in either a positive or negative direction, after the cannabis consumption experience. The data from all the participants are then combined into one measure of mood change on each of the six scales, ranging from 0-100% in either direction. In the following section (Study results) we present the mood changes at six separate times – at 30, 60, 90 and 120 minutes after consumption. We only show the mood effects that are backed with strong statistical power (90% level of confidence), which means that we are reasonably certain that most of the research participants actually experienced such mood changes.

Study results
The time evolution of the THC psychoactive effect and mood changes of the Surreal High Sun beverage is shown Figure 1. Below, we describe the results displayed in Figure 1.

Onset time and potency of the THC psychoactive effect (“HIGH” effect level):
According to the Cognalyzer® EEG analysis, the brainwaves of study subjects began exhibiting the impact of THC approximately 19 to 27 minutes after consuming a complete can of the Surreal High Sun beverage. The peak level of psychoactive effect (PEL) reached its maximum potency at minute 60 after consumption, measuring 31.6%.

Mood changes
After consuming a complete can of the Surreal High Sun beverage, consumers reported a 32.25% increase in relaxation levels after 30 minutes. The confidence level for this observed mood change was greater than 90%.

However, at the 60-minute mark, the relaxation enhancement decreased to 24.9%, and the mood change failed to achieve the 90% confidence level. This indicates that certain study subjects began experiencing a reduction in their sense of relaxation. Subsequently, in the second hour following consumption, consumers perceived a 33% increase in energy levels with a 90% confidence level.

The objective of our research is to enhance the precision and reliability of the cannabis experience associated with this particular product. We aspire to provide consumers with reliable information that enables them to make well-informed decisions regarding the purchase and consumption of cannabis products.

If you’re interested in using our portable neurotechnology for your own research or licensing these study results (our data) for educational, informational, promotional or research purposes, please contact Roy Agostino at