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APP| Published By AEIRC| https://doi.org/10.29052/2412-3188.v7.i1.2020.19-24 
 

Ann. psychophysiol. 
ISSN 2412-3188 (Online) | 2410-1354 (Print) 

 
 
Original Article                                                                                  

Psychophysiological effects of gum chewing 
on cognitive performance: A gender-based 
comparative study 
Saniya Sheikh, Amaila Fazal & Faizan Mirza  
Department of Physiology, University of Karachi  
 

Abstract 
Background: Chewing before performing a cognitive task increases oxygen levels 
in the Central Nervous System (CNS) areas important for processes of learning 
and memory. This study was done to evaluate and compare the effects of chewing 
gum on reaction time, visual short term memory, selective attention, verbal and 
non-verbal reasoning, and problem-solving ability in healthy male and female 
subjects. 
Methodology: The comparative, gender-based, interventional study was 
conducted involving 300 individuals placed in the control (n=150) and 
interventional group (n=150). Participants in the interventional group were 
required to chew gum till they completed the task. A questionnaire was designed 
to record the reaction time, memory, attention, executive and intellectual 
functioning and time took to solve each parameter. Each subject in both control 
and interventional group completed the questionnaire with and without chewing 
gum, respectively. Results for the two groups were compared using SPSS version 
20.0. 
Results: It was found that the gum chewing group performs significantly better 
than the control group, thus chewing gum significantly improves cognitive 
performance. These cognitive effects of chewing were comparable among the two 
genders but relatively more pronounced among male participants as compared to 
females.  
Conclusion: Chewing gum is positively associated with higher level of cognitive 
performance than controls. 
 

Keywords 
Chewing Gum, Mental Health Performance, Cognitive Skills, Intellectual 

Functioning, Reaction Time, Memory, Reasoning. 

 

 

 

Citation: Sheikh S, Fazal A, Mirza F. 
Psychophysiological effects of gum 
chewing on cognitive performance: A 
gender-based comparative study. APP. 
2020; 7(1):19-24 
 
Corresponding Author Email: 
faizan.mirza@uok.edu.pk 
 
DOI: 10.29052/2412-3188.v7.i1.2020.19-24 
 
Received 04/01/2020 
 
Accepted 15/07/2020 
 
Published 01/10/2020 
 
Copyright © The Author(s). 2020 This  
 is an open access article distributed 
under the terms of the Creative Commons 
Attribution 4.0 International License, 
which permits unrestricted use, 
distribution, and reproduction in any 
medium, provided the original author 
and source are credited.  
 

 

Funding: The author(s) received no 
specific funding for this work. 

Conflicts of Interests: The authors have 
declared that no competing interests 
exist. 
 

http://creativecommons.org/licenses/by/4.0/)
http://creativecommons.org/licenses/by/4.0/)


 

   

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Introduction  
Regardless of its fame and commerciality, 
gum chewing is an unusual action, it’s like 
eating without the act of associated digestion. 
The continual use of gum chewing has been 
promoted due to its breath enhancing 
properties for decades1. In 1939, the first 
study was conducted to determine whether 
chewing gum can reap any other benefits 
than breath enhancement and it was found 
that gum can reduce stress2. Subsequently, 
many other studies were conducted to 
investigate other positive effects of chewing 
gum, and it was concluded that chewing gum 
has many useful impacts on brain activity3,4.  
 
Chewing gum has found to help manage 
nicotine withdrawal, stress and acid reflux5,6. 
Many researchers figured out that chewing 
gum is involved in hyposalivation that 
removes debris from the teeth and also 
prevents caries1,7. For the dieter or health-
conscious individuals, the gum is a low-
calorie snack and a simple way to burn a few 
extra calories8. One of the most astounding 
findings is that researchers have recently 
established that chewing gum can improve 
the cognitive functioning of the brain areas 
controlling memory and attention9. The 
behavioral effects of chewing gum have been 
studied for over 80 years and much of the 
research has been concerned with increases 
in alertness and attention10. 
 
There are various conceivable components 
through which chewing gum may influence 
stress, alertness, and attention, for example, 
changes in the activity of the brain or 
elevated heart rate11. Moreover, the length 
over which the gum is chewed might 
generate impacts. Several studies have 
demonstrated that chewing helps to maintain 
cognitive functions in brain regions including 
the hippocampus, a CNS region vital for 
memory and learning11. 
 
Currently, there was a debate about the 
effects of gum chewing on cognition. Several 
well-controlled studies examined the effects 
of chewing gum on aspects of memory and 

attention in healthy young adults and found 
that gum chewing enhances cognitive 
functioning with regards to learning and 
memory. Because of these positive findings, 
there was quite some enthusiasm among 
researchers concerning this beneficial impact 
of gum chewing on cognition12.  
 
Thus, if the process of chewing gum really 
enhances memory then it could be used as a 
booster to increase learning and memory and 
also to positively impact the mental health 
performance of the healthy individuals. This 
study aimed to evaluate and compare the 
effects of chewing gum on the mental health 
performance among healthy male and female 
subjects by observing the comparative 
alterations in the reaction time, visual short 
term memory, selective attention, verbal and 
non-verbal reasoning, and problem-solving 
ability in the two genders.  
 

Methodology 
This comparative, gender-based, 
interventional study was conducted 
including 300 healthy individuals, including 
both males and females within 19-35 years of 
age. Subjects were randomly selected from 
University of Karachi and placed into two 
groups namely: a control (non-gum chewing) 
group and gum chewing group with 150 
subjects in each group. All the enrolled 
participants were required to fill out the 
study questionnaire. The control group had 
to answer the questionnaire without chewing 
gum, while the participants in the 
interventional group had to solve the 
questionnaire right after chewing gum until 
they completed the whole questionnaire. The 
questionnaire consisted of five cognitive 
parameters, including: 
 
Visual short-term memory that was an object 
learning task. The subjects were given a set of 
8 colored images and were told to remember 
as many of them as possible for 2 minutes. 
After two minutes, they were asked to point 
out the objects that were not present in the 
given list and the time duration was recorded 
for their task completion. 



 

   

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Selective attention was tested by using the 
digit symbol substitution test taken from the 
Wechsler Adult Intelligence Scale (WAIS). 
The subjects were asked to complete this test 
within 90 seconds. For each corrected item, 
the subject scored 1 and for the wrong ones 
zero was given. 
 
Verbal and non-verbal reasoning was 
determined by taking questions from the 
standard psychometric analysis of Alice 
Heim Group Ability Test (AH4) and WAIS. 
The subjects were asked to solve logical 
reasoning questions: 5 for verbal and 5 for 
non-verbal reasoning. All questions had one 
correct answer. The time taken by the subjects 
to solve the questions was noted.  
 

Problem-Solving ability was evaluated by 
doing calculations and solving word 
problems. The subjects were asked to solve 
given math problems, which were tested by 
two methods: calculations (Numerical) and 
word problems (Analytical mathematics/ 
Charts). The time taken by the subjects to 
solve the questions was noted. 

 
Reaction time was analyzed through the 
Ruler and Drop Method (Visual analysis). 
Once the measurements were taken, reaction 
time was calculated using the formula t= 
√2y/gₒ, where, Y = the distance you 
measured in centimeters, gₒ = the acceleration 
due to gravity constant (980 cm/sec2), and t = 
time in seconds.  
 
All the statistical calculations were done 
through IBM SPSS version 16.0. Descriptive 
statistics were used for categorical variables 
and independent “t” tests were performed 
for inferential statistics. Thereby, a p-value of 
less than 0.05 was determined as statistically 
significant. 
 

Result 
 

The study included 300 random healthy 
individuals, including both males and 
females between the ages 19-35 years. Our 
results showed improved cognitive 
performance following chewing gum in both 
genders (Table 1). 

 
Table 1: Mean-time taken by the individuals to complete the mental health  

performance tasks with and without chewing gum 

Study Parameters Male Female 

Control Intervention Control Intervention 

Visual Short Term Memory 12.7±5.0 10.3±5.2* 10.8±5.1 8.5±5.6* 

Selective Attention 42.4±10.4 40.7±8.7* 45.6±8.2 49.6±8.4 

Verbal Reasoning 53±31.9 63.5±26.5 59±24.1 56.6±18.0* 

Non-Verbal Reasoning 43±30.4 56.7±31.4 67±37.4 64.1±28.6* 

Problem-Solving Ability 71.7±43.2 63±22.8* 67±30.3 79.4±39.3 
Reaction Time 0.1±0.0 0.1±0.0* 0.2±0.0 0.2±0.0 
*Values are given as mean ± SD  
*Statistically Significant 

 

Visual short term memory was evaluated through the object learning task and it was found that less 
time was taken by subjects in the intervention group as compared to control group i.e. 10.3±5.2 vs 
12.7±5.0 among males and 8.5±5.6 vs 10.8±5.1 among females, thereby it could be determined that 
chewing gum increases visual short term memory, hence the mental health performance of both 
males and females. In case of selective attention, it was found that the mean time taken by the 
subjects in the intervention group was 40.7±8.7 among males while 49.6±8.4 among females which 
was comparatively high as compared to those in the control group. Thus, the comparison between 
the genders determines that males have better selective attention, problem-solving ability and 
reaction time than females. Whereas, the results for verbal and non-verbal reasoning were 
comparatively better among females.  



 

   

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Discussion 
Currently, there is an ongoing debate about 
the effects of gum chewing on cognition and 
mental health performance. To investigate 
the hypothesis that chewing gum increases 
cognitive performance, this study was 
designed to evaluate and compare the effects 
of chewing gum on cognitive performance 
among healthy male and female subjects. It 
was found that visual short term memory 
was increased among both the genders as a 
result of chewing gum which is consistent 
with the previous research, as it determined 
that chewing sugar-free gum improved 
aspects of verbal and visual memory13.  
 

The results clearly indicate that less time has 
been taken by both male and female subjects 
in performing short term memory tests while 
chewing gum. Here the robust effects of gum 
chewing may be due to increased delivery of 
glucose to the brain in association with 
increased metabolic activity14 and may also 
be associated with increased cerebellar blood 
flow during mastication15. This is also in 
agreement with the previous researches 
which showed that chewing immediately 
before a cognitive task increases oxygen 
levels in the Prefrontal Cortex (PFC) and 
hippocampus, both CNS areas important for 
processes of learning and memory16,17. 
Additionally, imaging studies have likewise 
uncovered sex-related hemispheric 
lateralization of amygdala function in 
connection to memory for emotional 
material. In particular, the reviews reliably 
displayed a special contribution of the left 
amygdala in memory for emotional material 
(for the most part visual pictures) in ladies, 
yet a special inclusion of the right amygdala 
in memory for similar material in males18-20. 
 
It was found that selective attention was 
increased among males but it was relatively 
decreased in females following chewing 
gum. This is because it has been assumed that 
the cognition-enhancing effect of gum 
chewing is caused by an increased release of 
insulin and a changed pattern of regional 
cerebral blood flow, in particular in fronto-

temporal regions of the brain13,21,22. 
Furthermore, it has been determined through 
the researches that the Inferior Parietal 
Lobule is larger in males than females23 and 
is related to the mathematical capacity and 
permits the brain to process data from senses 
and help in selective attention and 
perception24. 
 

Verbal and non-verbal reasoning was found 
to be decreased in males but it was increased 
in females. This may be due to the difference 
in brain morphology between the two 
genders, females have larger volumes, 
relative to cerebrum size, particularly in 
frontal and medial paralimbic cortices. 
Therefore, females have better verbal and 
nonverbal reasoning then males25. 
Furthermore, the left hemisphere, which is 
important to communication, is thicker in 
female-oriented brains25. Additionally, the 
brain of female processes verbal language 
simultaneously in the two sides 
(hemispheres) of the frontal brain, while men 
tend to process it on the left side only26. 
 

Furthermore, it was also found that problem-
solving ability was increased in males but it 
was decreased in females following chewing 
gum. This is in agreement with the research 
that men had larger volumes, relative to 
cerebrum size, in the fronto-medial cortex, 
the amygdala and the hypothalamus25. 
Therefore, men have better selective attention 
and problem-solving ability than females. 
Besides, males possess larger cerebra than 
women of the same age and health status, 
even if the body size differences are 
controlled statistically. Male brains are larger 
than female brains in all locations, though 
male enlargement was most prominent in the 
frontal and occipital poles, bilaterally27. The 
male differentiated brain has a thicker right 
hemisphere. This may be the reason males 
tend to be more spatial, and mathematical. 
 

Chewing gum had a positive effect on 
reaction time tests among males, enabling 
them to take less time to respond to the given 
visual stimulus as compared to females. This 
may be because males and females differ in 
the way they estimate time, judge speed of 



 

   

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things27, carry out mental mathematical 
calculations, orient in space and visualize 
objects in three dimensions and the way their 
brains process language information, 
emotion and cognition24. Males as compared 
to females can remain occupied with visual 
or hands-on learning tasks28. Moreover, 
chewing gum increases cerebral blood flow 
and also the supply of oxygen to the 
prefrontal cortex. 
 

Both genders are equivalent in insight, 
however, gender differences in mental health 
performance have been associated with their 
tendency to work differently. Males and 
females seem to utilize distinctive parts of the 
brain to encode memories, sense feelings, 
perceive faces, take care of specific issues and 
decisions. Without a doubt, when males and 
females of comparable knowledge and talent 
perform similarly well, their brains seem to 
go about it differently, as though nature had 
isolated outlines. Gender contrasts in the 
brain may assume a part in learning forms, 
speech development and progression of 
neurologically-based ailments. Gender 
contrasts should be considered in studying 
brain structure and capacity24. 
 
Males showed more positive effects while 
chewing gum than females. This is because 
the proportions of dark to white matter 
likewise contrast fundamentally between the 
genders in differing areas of the human 
cortex29. Men have roughly 6.5 times more 
grey matter in the mind than ladies, and 
ladies have around 10 times more white 
matter than men do30. And this grey matter is 
related to better cognitive performance and 
better reaction time in males. 

Conclusion 
It is concluded from the study results that 
chewing gum improves certain cognitive 
skills including; memory and intellectual 
functioning. Males showed relatively more 
positive effects while chewing gum than 
females. Thus it is positively associated with 
mental health performance, however the 
precise mechanism for improved cognitive 
functions due to gum chewing remains 

unclear. For a more complete picture of the 
relationship between physiological and 
cognitive aspects of chewing gum further 
investigations are required in beta and delta 
wave patterns. All these transformations in 
the after-test condition proposed that the 
pleasant sounds might develop a calm mind 
and body connection that significantly 
overcome stress to a certain degree. 

Acknowledgment  
The author want to acknowledge the 
students of University of Karachi that took 
part in the study and make this study 
possible. 

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