2012. Vol.3, No.3, 272-276
Published Online March 2012 in SciRes (
Copyright © 2012 SciRes.
Purpose in Life (Ikigai), a Frontal Lobe Function, Is a Natural
and Mentally Healthy Way to Cope with Stress
Riichiro Ishida
Division of Clinical Preventive Medicine, Graduate School of Medical and Dental Sciences,
Niigata University, Niigata, Japan
Received December 17th, 2011; revised January 15th, 2012; accepted February 17th, 2012
Stress can cause anxiety that creates imbalances in the autonomic nervous system and internal secretions
leading to mental and somatic disease. Purpose in life (PIL) and ikigai (two social attitudes) help indi-
viduals to integrate psychological events and effectively cope with stress. PIL/ikigai provides an intrinsic
motivation and is thought to develop primarily during adolescence. There is a correlation with such posi-
tive experiences as spending time in beautiful natural surroundings and exposure to warm human rela-
tionships at various developmental stages. PIL/ikigai is a physiological frontal lobe function. Adolescence
is a critical period of development for PIL/ikigai and neuronal connections are strengthened by secretion
of neurotransmitters such as dopamine and β-endorphin. We propose that there is an important physiol-
ogic role of PIL/ikigai and that critical periods of brain development influence development of PIL/ikigai.
Keywords: Stress; Anxiety; Happiness; Purpose in Life/Ikigai; Frontal Lobe
Happiness is defined psychologically as a multidimensional
construct composed of both emotional and cognitive elements
(Bekhet, Zauszniewski, & Nakhla, 2008; Hills & Argyle, 2001)
and is frequently identified as having positive affect or joy, a
high average level of satisfaction over a period of time, and the
absence of negative feelings such as depression and anxiety
(Argyle & Crossland, 1987; Bekhet et al., 2008). Additionally,
raising personal income or financial advantage which comes
from an external source, does not increase happiness which is a
subjective feeling of well-being (Easterlin, 1995; Easterlin,
McVey, Switek, Sawangfa, & Zweig, 2010; Frey & Stutzer,
2002; The Nihon Keizai Shimbun, January 20, 2012). The
amount of income is not always steady and this fact is de-
scribed in Japanese literature (Akutagawa, 1968). Many spe-
cialists propose that a new indicator of happiness, i.e., subjec-
tive well-being, should be developed rather than relying on
economic indicators, such as Gross National Product (GDP)
(The Nihon Keizai Shimbun, January 20, 2012). A person feels
happiness when he/she performs a task based on intrinsic moti-
vation, such as the pleasure of doing the task itself (Argyle &
Crossland, 1987; Hills & Argyle, 2001). Furthermore, a person
experiences pleasure when others offer praise or positive feed-
back (Akutagawa, 1968; Argyle & Crossland, 1987; Hills &
Argyle, 2001); however, praise is not always given, even if well
deserved (Akutagawa, 1968). Many people experience stress.
Any stress that contributes to anxiety causes an imbalance of
the autonomic nervous system and internal secretions and these
processes can lead to mental and somatic disease, such as de-
pression and coronary heart disease (Atkinson et al., 1996;
Ishida & Okada, 2006; Smith, Nolen-Hoeksema, Fredrickson,
& Loftus, 2003). Anxiety also sometimes leads to drug or al-
cohol dependence, or gambling problems, which have serious
consequences, such as psychiatric and somatic disease and fa-
mily dysfunction (Carlson, 2007; Neale, Netlleton, & Pickering,
2011). Many techniques for coping with and treating stress
have been proposed by philosophy, religion, literature (e.g.,
Camus, 1942; Damrosch, 2003; Jisei, 1600; Kierkegaard, 1844;
Moore, 1951; Phenix, 1966; Rousseau, 1762; Zeami, 1400) and
modern medicine (Freddi & Romàn-Pumar, 2011; Jetter, 1992;
Ogawa, 2005). However, the former are less evidenced based
and the latter deals mainly with patients.
Recently, we clarified that having purpose in life (PIL) and
ikigai can effectively help individuals to cope with stress (R.
Ishida, 2008a; R. Ishida, 2008b; R. Ishida, 2011; Ishida &
Okada, 2006; Ishida & Okada, 2011a; Ishida & Okada, 2011b;
Ishida & Okada, 2011c; Ishida, Okada, & Bando, 2004a; Ishida,
Okada, & Bando, 2004b). Additionally, brain research has ad-
vanced remarkably in recent years. In this paper, we propose
the psychological and physiological significance of PIL/ikigai.
Psychological Benefits of PIL/Ikigai
Every person naturally has a strong desire and drive to estab-
lish meaning in life. This is based on intrinsic motivation, which
develops more fully during adolescence compared to other de-
velopmental stages (Atkinson et al., 1996; Smith et al., 2003).
Lack of meaning in life or failure to find purpose leads to feel-
ings of emptiness and anxiety, which interfere with feelings of
subjective well being, i.e., happiness (Frankl, 1972a, 1972b,
1975; Kamiya, 2004). The term “PIL” is drawn from existen-
tialism that developed in Europe (Kida, 2006). The term “iki-
gai” appeared in Japanese classical literature and has been used
for a long time (Goto & Kamada, 1960). Both PIL and ikigai
have long histories and share a common core theme: “Every-
thing changes and life is a one time only opportunity. Every
person has a need for a meaningful life (Goto & Kamada, 1960;
Kida, 2006; Komatsu, 2009; Takagi, Ozawa, Atsumi, & Kin-
daichi, 1959).” Now, here, and ambition are considered impor-
tant in PIL/ikigai (R. Ishida, 2011; Ofman, 1980).
Our studies show that PIL/ikigai provides people with the
ability to integrate stressful psychological events from the past,
present, and future with less conflict or confusion (R. Ishida,
2008a; R. Ishida, 2008b; Ishida & Okada, 2006; Ishida &
Okada, 2011a; Ishida & Okada, 2011c; Ishida et al., 2004a;
Ishida et al., 2004b). This ability results in decreased anxiety
and lower sympathetic nervous system activity during events
that cause psychological and physical stress, such as when per-
forming a time-limited task that will be evaluated by others, or
when meeting a person for the first time (Ishida & Okada, 2006;
Ishida & Okada, 2011b; Ishida & Okada, 2011c; Ishida et al.,
2004a; Ishida et al., 2004b). PIL/ikigai also decreases psychiat-
ric/somatic symptoms that occur in stressful societies (Ishida &
Okada, 2006). This effective technique of coping with stress in
PIL/ikigai, in turn, influences the immune function and de-
creases the mortality risk (e.g., Kremer & Ironson, 2009); pre-
vious studies related to these findings were supported by R.
Ishida (2011). Furthermore persons with PIL/ikigai have traits
such as the ability to delay gratification, appreciate another’s
point of view, trust in a higher power, accept personal limita-
tions, or count personal blessings (Kamiya, 2004; Frankl, 1972a,
1972b, 1975). These protective mechanisms and personality
traits could be supported by brain functions related with pleas-
Brain, Neurotransmitters, and Stress
When we propose the importance of PIL/ikigai, it is neces-
sary to discuss preliminary evidence. The frontal lobe, which
has synaptic connections with other areas of brain, is more
developed in humans than other mammals. The functions in-
clude mental integration, planning for voluntary activity, and
ambition (Brodal, 1998). This suggests that PIL/ikigai corre-
lates with a frontal lobe function. The synaptic connections are
strengthened by repeated secretion of neurotransmitters such as
dopamine and β-endorphin which correlate with intrinsic moti-
vation and/or pleasure (Atkinson et al., 1996; Carlson, 2007;
Hawkes, 1992; Levinthal, 1988; Martin et al., 2009; Solomon et
al., 2011). The critical period of prefrontal lobe development is
adolescence (Atkinson et al., 1996; Brodal, 1998; Smith et al.,
2003), during which the synaptic connections and the function
of the organ develop more rapidly compared to other growth
periods (Brodal, 1998; Brown et al. 2001; Korelitz & Ernst,
2009; Mesulam, 2002).
Stress can have a psychological, physical or chemical etiol-
ogy, resulting from human relations, a change of environmental
temperature, restraints, hemorrhage, vulnus, or infusion of va-
rious drugs (e.g., Selye, 1936, 1973). Any kind of stress can
cause anxiety (e.g., Ishida & Okada, 2011a; Ishida & Okada,
2011b) and influence the autonomic nervous function control-
ling homeostasis, as stated by Cannon (1939). Selye (1936,
1973) proposed that any kind of stress induces a non-specific
response in the internal organs, such as adrenal cortex hyper-
trophy. The response process has three stages: the alarm reac-
tion, resistance, and exhaustion. Prolonged exhaustion leads to
This evidence shows that mind, brain function and chemical
traits of neurotransmitters are correlated with each other.
Development of PIL/Ikigai
Infants and young children are emotionally and psychology-
cally protected by parents and teachers. Older children and
adolescents are progressively separated from parental support
and exposed to real society. Real society offers multiple stimuli
that create serious stress; therefore the basic ability to cope with
stress occurs during adolescence. Adolescence is a critical pe-
riod for development of the frontal lobe and PIL/ikigai (Brodal,
1998; Brown et al., 2001; Korelitz & Ernst, 2009; Martin et al.,
2009). During adolescence every person has a chance to estab-
lish basic techniques for coping with stress, i.e., PIL/ikigai. The
establishment of PIL/ikigai during adolescence parallels, Rous-
seau’s proposal (1762) that adolescence is a period of “second
birth” compared with physiological birth.
We clarified that positive experiences, such as sympathetic
attitudes from others, affection for persons and events and
spending time in beautiful natural surroundings helps to deve-
lops PIL/ikigai (e.g., R. Ishida, 2008a). We also clarified that
motivation that is based on a strong need for approval, which is
then reinforced by excessive expectations from parents and
teachers, decreases PIL/ikigai (Ishida & Okada, 2011a). Future
research is needed to test the hypothesis that PIL/ikigai deve-
lops during adolescence.
Persons with or without PIL/Ikigai
Educators propose that every person should have a personal
philosophy that shapes and guides their contributions to society.
In other words, a strong PIL/ikigai helps individuals, their chil-
dren and strengthens the development of society (The Fuku-
shima Minyu, January 18, 2012). Regardless of occupation, age,
sex, or surroundings (R. Ishida, 2008b; Ishida & Okada, 2011b;
The Manichi Shimbun, October 31, 2001), people without PIL/
ikigai experience emptiness and anxiety, while those with PIL/
ikigai retain satisfaction, pleasure, and ambition even in harsh
environments (Frankl, 1972a, 1972b, 1975; Kamiya, 2004; Ku-
roda, 1969). Some examples of PIL/ikigai are discussed below.
The first examples relate to persons who do not have or fail
to draw strength from PIL/ikigai. With intensive study and
effort, students or youths succeeded in passing examinations to
enter universities or private companies; however after several
months, they felt empty and deeply depressed (I. Ishida, 2008;
Saito, 2008). A middle-aged employee had mental and somatic
disease because of workload and critical evaluations from his
supervisor and customers. He was strongly motivated to obtain
approval and praise from them (Hayashi, 2011). A man had
high status in his company and devoted himself to the job with
zealous responsibility, satisfaction and pleasure. After retire-
ment, his life had no meaning and he suffered depression and
alcohol dependence (Kanada, 2009). These persons lost mean-
ing in life during these periods of change or stress.
Other examples relate to persons with PIL/ikigai. “The East
Japan Enormous Earthquake (March 11, 2011)” was accompa-
nied by tsumani and serious incidents at a nuclear power plant
(Tokyo Electric Co., Ltd., in Fukushima Prefecture). Many
people were injured or killed and there was tremendous damage
to public and private property (The Niigata Nippo, March 12,
2011; The Asahi Shimbun, March 12, 2011). A geisha, who
had extensive training in the art of dancing, singing, and provi-
ding entertainment, lived in a gymnasium, after escaping from
her house. She taught her skills in traditional Japanese musical
instruments to other young geisha girls who traveled great dis-
tances to learn from her. Her students and other persons living
in the gymnasium experienced great satisfaction and pleasure
because she shared her skills (The Yomiuri Shimbun, July 10,
Copyright © 2012 SciRes. 273
2011). The hula girls in Fukushima Prefecture are famous and
many tourists attend their performances. Although most of the
dancing girls, their families and their theater were adversely
affected by the earthquake, they decided to continue the hula
for victims and people living in other prefectures. Recently, the
theater was rebuilt by local efforts, thus the dancing girls and
supporters were glad that the hula dancing continued (The Fu-
kushima Mimpo, January 18, 2012). “Soma-ryu-yamaodori” is
a traditional dance of the area of Soma in Fukushima Prefecture.
However the earthquake killed some members of the dance
troupe, while others had to evacuate to other areas; thus a
planned exhibition was cancelled. Recently, the members of the
troupe met and overcame the difficulties and took their per-
formance to other towns because their town was too extensively
damaged. Many people, including residents from the troupe’s
hometown were moved to tears during the performance. The
troupe desired to dance in their hometown to pay tribute to the
memory of those lost and to encourage survivors to rebuild the
town. (The Fukushima Minyu, January 16, 2012). Additional
examples also relate to persons with PIL/ikigai during situa-
tions of routine life. Alcohol dependence is an important and
serious issue in most countries. Researchers in the United
States have studied the correlation between drinking alcohol
and secretion of β-endorphin for a long time. They successfully
clarified the correlation and their work could lead to the devel-
opment of new treatments (The Japan Agricultural News, Janu-
ary 12, 2012). A farmer and his family in Japan had a strong
desire to provide high quality flowers at a lower cost. The
farmer, his wife, and his father and mother developed new
techniques leading to effective results (The Japan Agricultural
News, January 17, 2012). Many men in India work to deliver
lunch to customers in offices and homes every day. They are
very busy and not rich; however, they take pride in offering
good service to their customers. They have few failures and
seldom deliver the wrong lunch to the wrong person (The San-
kei Shimbun, January 22, 2012). Many counselors in different
countries support persons with drug or alcohol dependence, or
gambling problems. Successfully helping clients with depend-
ency issues to achieve in meaning of life, (i.e., PIL/ikigai for
clients) results in subjective well-being for the counselors (e.g.,
Gavle, 2009; Neale, Nettleton, & Pickering, 2011; Oei, &
Gordon, 2008; Waisberg & Porter, 1994).
These examples demonstrate that contributing to others’
pleasure rather than receiving praise from others creates subjec-
tive well-being for the doers.
Proposals for Development of PIL/Ikigai
in Daily Life
Not only recent evidence (e. g., R. Ishida, 2008a; Brown,
Keynes, & Lumsden, 2001; Bundra, 1979) but also classical
documents (e.g., Rousseau, 1762; Zeami, 1940) contribute to
the development of PIL/ikigai. We propose that development of
PIL/ikigai occurs according to both evidence and classical the-
ory. Parents, teachers, and society should offer children various
kinds of positive experiences during each developmental stage,
starting in infancy, with consideration for each critical devel-
opmental period of the brain. Spending sufficient time in beau-
tiful natural surroundings where ponds and rivers exist; where
trees, flowers, and plants grow; and insects, fishes, and mam-
mals live, provides opportunities for children to explore, catch
fish, and collect plants or insects with their friends. These ex-
periences enrich their hearts and minds and allow them to feel
pleasure and comfort. Other opportunities should include, en-
couraging them to sing a wide variety of songs; listening sym-
pathetically; praising moderately; encouraging interesting pro-
jects such as making a house out of wood using a hammer and a
saw; or using small machines and puzzles which allow the child
to take the object apart and put it back together again. Such
activities encourage solving problems using the mind and the
hands. These types of activities could contribute to the ability to
integrate psychological events and maximize sensory stimuli.
These good events are then memorized by the brain. However,
parents should not force children to learn too much or expect
them to grasp complex knowledge that is beyond their level.
Ignoring the critical period and their interests and giving too
many detailed instructions about their behavior does not help
them to develop the ability to cope with stress. Overzealous
expectations can prevent natural and sufficient development of
the brain and this could ultimately lead to a reduced ability to
cope with stress in the future. Many youth study at senior high
school and university or work in real society, and these are
significant activities that are important for the self and the soci-
ety. It should be noted that youth can be pushed to be too busy
or to have an excessive need for approval. Their motivation and
sense of self may become locked into going to a “good univer-
sity”, being hired by a “good company”, and aspiring to a
“good status”. Fixation on reaching these “good” goals can
prevent the chance to think deeply and create PIL/ikigai as their
intrinsic motivation. It is important for youth, however, to have
many positive and interesting challenges which vary according
to individual interests; for example, reading books, playing
sports with friends, drawing pictures, playing and/or listening
to music, going on tours, or doing volunteer work. These pro-
posals do not necessarily mean that all the activities should
continue during their lifetime. Challenging experiences that
occur from infancy to adolescence produce satisfaction and
pleasure accompanied by secretion of neurotransmitters such as
dopamine and β-endorphin. The brain memorizes the experi-
ences and helps them to establish and/or modify PIL/ikigai in
the future.
A Brief Look at Evolution
Cannon (1939) noted that, “only by understanding the wis-
dom of the body, shall we attain that mastery of disease and
pain which will enable us to relieve the burden of mankind.” It
is said evolution is performed over time resulting in survival of
the species, i.e., adaptation to changed environments (Solomon
et al., 2011). Successful adaptation to environments causes in-
creased satisfaction, pleasure and less anxiety (e.g., R. Ishida,
2008b; Ishida & Okada, 2006). By understanding PIL/ikigai
(using frontal lobe function), we can understand one of the
wisdoms of the body. Limited physical evidence is currently
available; thus, we hypothesize that a mixture of positive ex-
periences, such as being in beautiful natural surroundings and
having warm human relationships influence evolution over time.
These positive experiences contribute to the development of
PIL/ikigai as an effective technique of coping with stress.
The human brain, especially the frontal lobe, is highly
evolved compared to other mammals. Humans have the ability
to integrate experiences and adolescence is a critical period for
Copyright © 2012 SciRes.
development. It is natural for all humans to establish PIL/ikigai
using the frontal lobe. PIL/ikigai is an effective technique for
coping with stress and could influence longevity.
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