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Tourism Management 44 (2014) 140e148

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Tourism Management

journal homepage: www.elsevier .com/locate/ tourman

Case Study

Psychoneurobiochemistry of tourism marketing

Erdogan Koc a,*, Hakan Boz b,1

aBalikesir University, Bandirma Faculty of Economics and Administrative Sciences, Department of Business Administration, Bandirma Kampusu, Bandirma,Balikesir, TurkeybUsak University, School of Applied Sciences, 1 Eylul Kampusu, Usak, Turkey

a r t i c l e i n f o

Article history:Received 7 March 2013Accepted 7 March 2014

Keywords:PsychoneurobiochemistryPsychologyPhysiologyNeurotransmittersTourismSerotoninConsumer behaviourNeuromarketing

* Corresponding author. Tel.: þ90 266 7380945x42E-mail addresses: erdogankoc@balikesir.edu.tr, erd

hakan.boz@usak.edu.tr (H. Boz).1 Tel.: þ90 276 2212121x2282.

http://dx.doi.org/10.1016/j.tourman.2014.03.0020261-5177/� 2014 Elsevier Ltd. All rights reserved.

a b s t r a c t

This study offers a unique approach to consumer/tourist behaviour called psychoneurobiochemistry andaims to explore the possible and potential influences of psychoneurobiochemical factors on tourismmarketing. The study with a multidisciplinary approach analyzes and syntheses the psychological,neurological, biological and chemical research findings in terms of their implications for tourism mar-keting. The study particularly looks at neurotransmitters such as serotonin and dopamine; melatoninhormone; photoperiod and circadian rhythm and emotions.

� 2014 Elsevier Ltd. All rights reserved.

1. Introduction

Tourism is the largest industry in the world both in terms of therevenues generated and the number of people employed. Tourismindustry’s contribution toworldwide gross domestic product (GDP)and employment was 5% and 7% respectively in 2011 (WTO, 2012).In 2011 over one billion people participated in tourism activitiesgenerating an income of $1030 billion (WTO, 2012). More impor-tantly it is estimated that these figures have been reached with theinvolvement of only 4% of thewholeworld population participatingin tourism activities. This means that the growth potential oftourism industry is phenomenal. It is estimated that in 2020tourism industry will generate an income of $2 trillion with theparticipation of 2.6 billion people.

Therefore, the studies tourism industry is important both on amacro level, in terms of its contribution to countries’ economies,but also at micro level, i.e. at firm level, in terms of achievingcompetitive advantage. Based on this background this studythrough a multidisciplinary approach analyzes and syntheses thepsychological, neurological, biological and chemical research find-ings in terms of their implications for tourismmarketing. The study

2.ogankoc@yahoo.com (E. Koc),

is important as in most research studies of consumer behaviourdata collected from the participants are based on their own ac-counts and evaluations of consumption situations. However, inmany instances, data collected through the accounts and evalua-tions of the participants may not reflect actual truth. This may bedue to two factors. Firstly, the participants in research studies mayhave hidden motives, which even they themselves may not beaware of Koc (2013a). Secondly, in many instances people mayengage in impressionmanagement, i.e. a goal-directed conscious orunconscious activity in which people attempt to influence theperceptions of others about a person, object or event throughregulating and controlling information in social interaction(Goffman, 1959).

2. Psychoneurobiochemistry of tourism marketing

The term psychoneurobiochemistry has been coined by theauthors of this study to refer to a group of often studied factors inthe disciplines of psychology, neurology, biology and chemistry.These factors influence tourism consumers both in terms of theirphysiological and psychological existences. These two existencesare intertwined, through a continuous interaction in which oneinfluences the other. The physiological and psychological exis-tences of consumers are analyzed and synthesized in this study byexploring neurotransmitters and hormones such as serotonin,dopamine and melatonin; biological factors such as photoperiod

E. Koc, H. Boz / Tourism Management 44 (2014) 140e148 141

and circadian rhythm and psychological factors such emotions andmood.

2.1. Serotonin

In human brain information as a response to a stimuli, iscommunicated through neurotransmitters such as serotonin anddopamine (Artigas, Romero, de Montigny, & Blier, 1996; Graeff,Guimaraes, de Andrade, & Deakin, 1996; Griebel, 1995). A neuro-transmitter, a brain chemical, communicates informationthroughout the human brain and body. A neurotransmitter (orsynaptic transmitter) communicates information between neuronsby themovement of chemicals or electrical signals across a synapse,a structure that permits a neuron (or nerve cell) to pass an electricalor chemical signal to another cell (neural or otherwise) (Gaspar,Cases, & Maroteaux, 2003; Gross et al., 2002; del Olmo et al., 1998).

Serotonin (5-HT), usually referred as the happiness hormone, isa neurotransmitter that influences a vital section of the brain, calledthe limbic system. The limbic system supports a variety of func-tions, including emotion, behaviour, motivation, long-term mem-ory, and olfaction. Serotonin is primarily responsible for emotionallife of human beings, and has a great deal to do with the formationof memories (Siegel, 2005).

There is plenty of research evidence, across many speciesincluding humans, suggesting that as the secretion (discharge) ofserotonin decreases, the tendency to aggression increases (Pihl &LeMarquand, 1998; Siegel, 2005). Unusually low levels of seroto-nin are also associated with impulsive and erratic behaviours(Winstanley, 2007). Impulsive behaviour motivates consumers toseek immediate rewards, rather than choosing the “delayed”reward (or long term positive balance/need satisfaction) by havingself-control (Bizot, Le Bihan, Puech, Hamon, & Thiebot, 1999),Therefore, impulsivity may be lead to inappropriate or poor deci-sion making as it favours immediate outcomes over delayed out-comes. Research shows that as much as 95% of all consumerpurchases of products and services could be impulse purchases(Bayley & Nancarrow, 1998; Beatty & Ferrell, 1998; Bellenger,Robertson, & Hirschman, 1978; Cobb & Hoyer, 1986; Coley, 2002;Gutierrez, 2004; Kacen & Lee, 2002; Kollat & Willet, 1967;Parboteeah, 2005; Piron, 1991; Rook, 1987; Rook & Fisher, 1995;Solomon, 2003; Stern, 1962; Tendai & Crispen, 2009; Verplanken& Herabadi, 2001; Virvilaite, Saladiene, & Bagdonaite, 2009; Vohs& Faber, 2007).

The level of impulsivity of customers may be increased in pur-chasing environments through marketing stimuli, despite itsethical repercussions. In the tourism industry the servicescape (thephysical surroundings) of hotels, restaurants, travel agencies andthe marketing communications messages of all sorts, e.g. web sites,brochures, etc., may be designed in such a manner to encourageand induce customers to engage in reward seeking behaviour. Inthis way the potential of stimulation of the interaction with theservicescape and the atmosphere, and the potential of engaging inimpulsive behaviour, can be triggered (Donovan & Rossiter, 1982;Hart & Davies, 1996; Oakes, 2000; Tai & Fung 1997; Verplanken &Herabadi, 2001).

Serotonin is synthesized in two stages from the dietary aminoacid tryptophan. The first stage is catalyzed by the enzyme tryp-tophan hydroxylase. The low affinity of the enzyme for tryptophanmakes this stage rate-limiting for serotonin synthesis e in otherwords, serotonin can be produced only as fast as this enzyme canhydroxylate tryptophan. The rate of serotonin synthesis is deter-mined, in part, by the availability of tryptophan in the brain. If thereis more tryptophan, there will be more tryptophan (Bear, Connors,& Paradiso, 1996). Therefore the dietary alterations of the serotoninprecursor tryptophan can influence the levels of serotonin.

Tryptophan is a fundamental amino acid for the synthesis ofprotein, and it cannot be synthesized by the human organism andhence must be ingested in the diet. After an amount of the intake oftryptophan, the tryptophan is absorbed into the capillaries (minuteblood vessels) in the intestinal wall. A small amount of the tryp-tophan remains free, while the majority of it (about 80%e90%) istransported bound to albumin through the blood and into the brain(Paredes, Barriga, Reiter, & Rodríguez, 2009). Research findingsshow that concentration of the amino acid tryptophan is signifi-cantly lower in psychologically depressed patients.

The level of the serotonin appears to play a major role in thegeneration and modulation of various cognitive and behaviouralfunctions such as sleep, mood, pain, addiction, locomotion, sexualactivity, depression, anxiety, alcohol abuse, aggression and learning(Artigas et al., 1996; Graeff, Guimaraes, de Andrade, & Deakin, 1996;Griebel, 1995; Meneses, 1999; Ramboz et al., 1998; Rocha et al.,1998). Additionally, failure in serotonergic systems cause ofmental disorders such as schizophrenia, migraine, depression,suicidal tryptophan, infantile autism, eating disorders, and obses-sive compulsive disorder (Heisler et al., 1998; Murphy, Wichems, Li,& Heils, 1999; Parks, Robinson, Sibille, Shenk, & Toth, 1998; Parsons,Kerr, & Tecott, 2001; Ramboz et al., 1998; Rocha et al., 1998), heartdisease (Nebigil & Maroteaux, 2001), asthma (Barnes, Chung, &Page, 1998) and phagocytosis (Freire-Garabal et al., 2003).

Increasing tryptophan levels can increase serotonin synthesis asmuch as twofold (Young & Gauthier, 1981), while decreasingtryptophan availability can cause a substantial decline in serotoninsynthesis and turnover (Carpenter, Nagell, & Tomasello, 1998;Nishizawa et al., 1997).

Moreover, the serotonin pathway plays an indispensable role inbrain development processes such as neurogenesis and axonalbranching during various stages of development (Gaspar et al.,2003; Gross et al., 2002; del Olmo et al., 1998). Measurement ofserotonin levels during normal human aging has shown age-dependent decreases in certain, but not all, brain regions. Overallresearch findings relating to the level of serotonin and aging sug-gest that the level of serotonin in brain decreases with age (Ko,King, Gordon, & Crisp, 1997; Rehman & Masson, 2001). However,a distinction needs to be made in terms of the phases of aging as inthe early to mid-phase of aging, the level of serotonin secretion inthe brain increases (Cassel et al. 2005; Murakami, Bessinger,Hellmann, & Murakami, 2008; Sapolsky & Donnelly, 1985; VanNueten & Janssens, 1986). During the late phase of aging, levels ofserotonin are reduced due to the loss of the serotonin-secretingneurons (Mattson, Maudsley, & Martin, 2004). The increase of se-rotonin secretion in the brain in the early to mid-phase of aging ismainly to do with the relative inability to turn off cortisol pro-duction (Sapolsky & Donnelly, 1985). Hypothyroidism increases theformation of serotonin, as does cortisol (Henley, Meng, O’Brien,McCarthy, & Sockloskie, 1998; Neckers & Sze, 1975). This is why,in general, in the early phase of aging people feel less stressed anddepressed. In the early to mid-phase of aging people become moretolerable towards things around themselves and be more satisfiedwith who they are and what they have (Koc, 2013a). This in turnmay reduce the personality conflicts emanating from the gap be-tween the actual and the ideal self-concepts of individuals.

Exposure to bright light can also trigger tryptophan, serotoninprecursor, without the extra intake of drugs and food and bever-ages. Bright light is a standard treatment for seasonal depression,but a few studies also suggest that it is an effective treatment fornonseasonal depression and it also soothes the depressed mood(Carlsson, Svennerhold, & Winblad, 1980; Golden et al., 2005; Lamet al., 1999). It is known that while 90% of Finnish people experienceseasonal affective disorders (Avery et al., 2001), only 10% of Italiansexperience seasonal affective disorders. Tourism and hospitality

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businesses operating in the sun and sea holidays market (e.g. firmsin countries such Turkey and Spain) may target countries with af-fective seasonal disorders with tourism products specificallydesigned to reduce seasonal affective disorders.

Additionally, doing physical exercise can also trigger the level oftryptophan (Blomstrand, 2001; Chaouloff, Elghozi, Guezennec, &Laude, 1985; Chaouloff, Laude, Guezennec, & Elghozi, 1986;Gomez-Merino, Béquet, Berthelot, Chennaoui, & Guezennec,2001; Jacobs & Fornal, 1999; Meeusen et al., 1997; Wilson &Marsden, 1996). For instance, as a form of physical exercise,running, on its own, may trigger a 30% increase in Tryptophanlevels in the brain (Chaouloff, Laude, & Elghozi, 1989).

As tryptophan supplements in the form of drugs can causecancer and various other serious health complications (Ashidaet al., 1998; Nemoto, Kusumi, Takayama, Nagao, & Sugimura,1979; Suzuki, Sone, Kawamura, & Ishihara, 2008; Yamazoe, Ishii,Kamataki, & Kato, 1981; Yamazoe, Ishii, Kamataki, Kato, &Sugimura, 1980), the triggering of tryptophan through physicalexercise and intake of serotonin rich food and beverages is rec-ommended. Based on the above research findings the hospitalityestablishments may design their marketing communication mixcovering the following aspects and issues:

� physical and recreational activities� exposure to daylight� the serving of food and beverages

The hospitality establishments may be recommended to investin facilities so that they offer a wider variety of physical and rec-reational activities. The participation of guests in the physical andrecreational activities can be increased through the provision ofappropriate information and the use of various inducements. Thefacilities in the hospitality establishments such as restaurants maybe designed in such a way so that guests are exposed to more hoursof sunlight. Finally, the menus can be re-constructed with a view toadd more foods and beverages with serotonin or serotonin richfood items and beverages. Table 1 shows the amount of serotonin invarious food items and beverages (Feldman & Lee, 1985).

In addition to the above food and beverages listed in Table 1, anumber of other foods and beverages contain serotonin also,though in lower quantities. For instance, food items such as beef-steak (broiled), ham (baked), chicken (baked), fish (broiled),Parmesan cheese, corn, potatoes, rice, and wheat germ containserotonin of about (<0.1 mg/g). Beverages such as coffee, tea, milk,beer and Chianti wine contain serotonin of about (<1 ml/ml).

Table 1Serotonin content of various food items.

Serotonin content foods

Amount of serotoninmg ¼ micro gram

Amount of serotoninmg ¼ micro gram

Plantain 30 � 7.5 mg/g Highserotonin>3.0 mg/g

Avocados Haas(California)

1.6 � 0.40 mg/g Modsero>3.Pineapple 17 � 5.1 mg/g Avocados Fuerte

(California)1.5 � 0.21 mg/g

Banana 15 � 2.4 mg/g Avocados Booth(Florida)

0.2 � 0.04 mg/g

Kiwi Fruit 5,8 � 0.9 mg/g Dates 1.3 � mg/gPlums 4.7 � 0.8 mg/g Grapefruit 0.9 � mg/gTomatoes 3.2 � 0.6 mg/g Cantaloupe 0.9 � mg/gButternuts 398 � 90 mg/g Honeydew Melon 0.6 � mg/gBlack Walnuts 304 � 46 mg/g Olives (Black) 0.2 � mg/gEnglish Walnuts 87 � 20 mg/g Broccoli 0.2 � mg/gShagbark 143 � 23 mg/g Eggplant 0.2 � mg/gMockernut 67 � 13 mg/g Figs 0.2 � mg/gPecans 29 � 4 mg/g Spinach 0.1 � mg/gSweet Pignuts 25 � 8 mg/g Cauliflower 0.1 � mg/g

Research also shows that a meal high in carbohydrate increases therate that tryptophan enters the brain, leading to an increase in thelevel of the neurotransmitter serotonin which in turn modulatesthe mood (Benton & Donohoe, 1999).

2.2. Dopamine

Dopamine (DA) is a neurotransmitter in the central and pe-ripheral nervous systems where it regulates physical and psycho-logical activities (Bergman, 2006; Matsunaga et al., 2008; Sallis,2000). Within the central nervous system (CNS), dopamine isknown to regulate emotion, reward, cognition, memory, endocrinefunctions such as the secretion of insulin, the appetite, the pro-duction of erythropoietin and active vitamin D, and motor control.Changes in dopaminergic transmission are known to cause anumber of neurological and psychiatric disorders, including Par-kinson’s disease, Tourette’s syndrome, attention-deficit hyperac-tivity disorder (ADHD), schizophrenia, and substance use. Thesedisorders are all treated with drugs that either enhance or impededopaminergic transmission (Madras, Miller, & Fischman, 2002;Suzan, Mark, José, John, & Martin, 1997). Dopamine is a derivativeof the aromatic amino acids phenylalanine and tyrosine and aprecursor of the neurotransmitters norepinephrine and epineph-rine (Comings et al., 1993; Schetz & Sibley, 2007).

Dopaminergic neurons give rise to four dopaminergic pathways:the nigrostriatal, the mesolimbic, the mesocortical and tuber-oinfundibular pathways. These pathways are involved in the controlof movement, hormone synthesis and secretion, learning, motiva-tion and reward. Rewards are experienced as making things betterandhence liked, desired,wanted andpursued (Berridge&Robinson,1998; Di Chiara & Bassareo, 2007). Therefore, consumption of re-wards (e.g. devouring palatable food in an all-inclusive hotel) pro-duces hedonic consequences (pleasure) which induce learningprocesses that encompass of a wide variety of sub activities toensure future satisfactions. The learning processes may encompassthe following sub activities: liking the rewarding goal, learning cuesthat predict its availability, actions that allow its consumption;assigning value and motivational status to the reward so that theperson can evaluate and select among numerous behavioural op-tions; and determine what level of resources to be used and effortsto be exerted to obtain that specific goal. Need states such as hungerand thirst increase the incentive salience of “reward-related cues”and the reward itself (Kelley & Berridge, 2002).

Research studies show that dopaminergic system influencedecision making (Schultz, 2007), ability to analyze and evaluate

Distribution of serotonin in areas of fruits

Amount of serotoninmg ¼ micro gram

Amount of serotoninmg ¼ micro gram

eratetonin0 mg/g

Banana Pineapple

Peel 31.8 mg/g Peel 2.7 mg/g

Pulp-Slice 14.0 mg/g Pulp-Edge 31.5 mg/g

Pulp-Centre 26.6 mg/g Core-Centre 8.7 mg/gPulp-Edge 6.3 mg/g KIWIPlantain Peel 0.3 mg/gPeel 17.4 mg/g Pulp-Edge 6.8 mg/gPulp-Slice 20.0 mg/g Pulp-Centre 3.0 mg/gPulp-Centre 27.7 mg/g TomatoesPulp-Edge 8.8 mg/g Pulp 3.7 mg/gAvocado-Haas Seed 3.2 mg/gPulp 1.10 mg/g Peel 0.08 mg/gSeed 0.06 mg/g

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(de Bruijn, Sabbe, Hulstın, Ruıgt, & Verkes, 2006; Cohen, Young,Baek, Kessler, & Ranganath, 2005; Knutson, Westdorp, Kaiser, &Hommer, 2000; Morris, Nevet, Arkadir, Vaadia, & Bergman, 2006;Salamone, Correa, Farrar, & Mıngote, 2007; Schultz & Dickinson,2000; Vrshek-Schallhorn, Wahlstrom, Benolkin, White, & Luciana,2006) (e.g. comparing, analyzing and evaluating various hospitalityservices and their marketing communications messages) andability to act towards the chosen decision (Cromwell, Berridge,Drago, & Levine, 1998; Daberkow, Kesner, & Keefe, 2005).

The reward mechanism is essential in outward behaviour ofpeople. When making decisions (e.g. purchase and consumptiondecisions) people may usually engage in cost-benefit analysis. Inevery transaction the goal of each and every individual is to reducecosts and increase benefits (Phillips, Walton, & Jhou, 2007;Salamone & Correa, 2002; Walton, Kennerley, Bannerman,Phıllıps, & Rushworth, 2006). Having carried out a cost-benefitanalysis dopamine enables an individual to engage in approach ornot approach behaviour (Both, Everaerd, Laan, & Gooren, 2005;Mclean, Rubinszteın, Robbins, & Sahakian, 2004; Salamone et al.,2007; Satoh, Nakai, Sato, & Kimura, 2003). Dopamine causes theactivation of the areas responsible for rewards in human brain.After encountering stimuli the neurotransmitter dopamine be-comes active and stimulates the individual to behave in a certainmanner. In order to balance the serotonin levels of guests hotelsmay develop and serve menus which contain high levels of tryp-tophan such chocolate, oat, beans, bananas, milk, yogurt, eggs,raisins, cottage cheese, fish, beef, turkey, chicken, sesame,hazelnuts, peanuts, almonds, citrus fruits, tomatoes, pumpkin andgreen tea.

The use of food items containing too much glucose, sodium andfat may trigger the reward and pleasure mechanisms in consumers.However, it is known that the excessive use of glucose, sodium andfat are extremely dangerous for the physiological and psychologicalwell-being of consumers. Westomer and Marangell’s (2002)research in different countries show that there is a strong corre-lation between glucose consumption and the prevalence ofdepression in the society.

Many of the functions of dopamine pathways closely relate totourists’ purchase (e.g. to be motivated to buy and consume aparticular type of holiday, to learn frommarketing communicationsmessages and from other people, to seek rewards in the form ofbeing alert for certain types of sales incentives) reward seeking andmonitoring sales incentives and consumption (consumption offood and beverages in a hotel) decisions (Besson & Louilot, 1995;Gerfen, 1992; Graybiel, 1995; Jaskiw & Weinberger, 1992; Koob,1992; LeMoal & Simon, 1991; Marsden, 1992; Picetti et al., 1997).

2.3. Melatonin, circadian rhythm and photoperiod

Melatonin is a hormone secreted by the pineal gland in thebrain. It helps regulate other hormones and maintains the body’sregular sleep routine and the circadian rhythm (Atkinson, Drust,Reilly, & Waterhouse, 2003; Lewy, Emens, Lefler, Yuhas, &Jackman, 2005; Pandi-Perumal et al., 2006). The circadian rhythmis an internal 24-hour internal clock that plays a critical role inwhen people fall asleep and wake up (Lewy et al., 2005). Sleepdisorders may have a wide variety of negative consequencesranging from fatigue, depression, bad mood to a lack of cognitiveability in terms of thinking, analysing andmaking decisions (McCoy& Strecker, 2011). When there is full moon many people may totend to have restless sleep and experience the negative conse-quences of melatonin deficiency.

When it is dark, human body produces more melatonin; andwhen it is light, the production of melatonin drops. An exposure tobright light in the evening, or exposure to too little light during the

day can disrupt a person’s normal melatonin cycles (Eastman,1990;Eastman, Jin, Kyem, & Toledano, 1995). In general jet lag, shift work,and poor vision can usually disrupt melatonin cycles. In humanbeings circulating levels of the melatonin hormone vary in a dailycycle, thereby allowing the entertainment of the circadian rhythmsof several biological functions (Watson, 2011).

Photoperiod is the duration of a human being’s daily exposure tolight, considered especially with regard to the effect of the exposureon several functions, including sleep, energy, mood, growth anddevelopment. Apart from the daylight, the availability and the levelof serotonin also plays a key role in the endogenous regulation ofthe circadian clock (Glass, DiNardo, & Ehlen 2000). Studiesdemonstrate that melatonin supplements may help individualswith disrupted circadian rhythms (such as people with jet lag orthose who work night shifts) and those with low melatonin levels(such as some elder people and people with schizophrenia) to havea better sleep (Altun & Altun, 2007; Arendt, 2000; Bendz & Scates,2010). A review of clinical studies suggests that melatonin sup-plements may help prevent jet lag, particularly in people who crossfive or more time zones (Caspi, 2004).

Research findings show that melatonin secretion levels maychange according to age and the aging process (Paredes et al. 2009)(See Fig. 1).

The level of melatonin production normally decreases as peopleget older and this may make people more prone many types ofhealth problems. For example, sleeping disorders may be associ-ated with low levels of melatonin. People find it difficult to sleepand tend to wake up early in the morning as they get older (Raloff,1998; Vitiello, 2006; Yoon et al., 2003). Additionally, as people getolder melatonin production declines and people may become moreprone to several types of cancers. Extreme exposure to daylight,especially at night time, in childhood may cause certain types ofcancers such as leukaemia (Leitgeb, 2011).

Marketing of services such as the services of hospitality estab-lishments differ from the marketing of tangible goods. In manycases, the consumer, i.e. the tourist needs to travel to the premisesof the service provider, for the consumption of services. Theduration of travelling may take many hours and this in turn maycause a change in the body clock or the circadian rhythm. Asexplained above jet lag, medically referred to as desynchronosis, isa physiological condition which results from alterations to thebody’s circadian rhythms resulting from rapid long-distancetransmeridian (eastewest or westeeast) travel by a (typically jet)aircraft (Waterhouse, Reilly, & Edwards, 2004). Jet lag is worsewhen people move from west to east as the human body finds itharder to adapt to a shorter day than a longer one. As most of theflow in tourism is from the west to the east (WTO, 2011), jet lagshould be considered as an important phenomena in tourism fromthe perspective of tourist satisfaction.

The jet lag impairs psychological and physiological healththrough sleep disorders, lack of energy and concentration, memorylapses and depressed mood. The condition of jet lag may lastseveral days until one is fully adjusted to the new time zone, and arecovery rate of one day per time zone crossed is a suggestedguideline (Waterhouse, Reilly, Atkinson, & Edwards, 2007). Nomatter how good the services of a hospitality establishment, e.g. ahotel, the guest suffering from jet-lag may not be able to enjoy her/his holidays as much as s/he expected. Consequently, the touristmay finish her/his holiday not as much satisfied as s/he expected.For this reason, the hospitality establishments are recommended tomake a note of take the point of departure of the guest. Secondlybased on the point of departure, the guest can be advised accord-ingly. For instance guests travelling to the Mediterranean from theUnited States may be advised to go out to be exposed to daylight afew hours before people usually wake up in the point of departure.

Fig. 1. Melatonin levels throughout lifespan.Source: Paredes et al. (2009).

Table 2Levels of melatonin in representative common vegetables and fruits.

Melatonin content foods

Amount of melatoninng/100 g

Amount of melatoninng/100 g

Apple 47.6 � 3.1 Kiwi Fruit 24.4 � 1.7Asparagus 9.5 � 3.2 Onion 31.5 � 4.8Banana 65.5 Pineapple 36.2 � 8.4Beetroot 0.2 Pomegranate 16.8Cabbage 107.4 � 7.3 Radish 75.8Carrot 55,3 � 11,9 Rice 1006.0 � 58.5Corn 1366.1 � 465.1 Strawberry 13.6Cucumber 59.2 Tomato 50.6Garlic 58.7

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The hotel management may be recommended tomake sure thattourists get a good night’s sleep upon their arrival. As dehydrationcan intensify the effects of jet lag, upon their arrival the touristsmay be offered a variety of beverages upon their arrival. Addi-tionally, physical exercise and melatonin supplements can reducethe effects of jet lag and the impairment of circadian rhythm. Froma melatonin, photoperiod and circadian rhythm perspectives thehospitality establishment is advised to make sure that when guestsdraw the curtains no light goes inside the rooms. The outside lightsof the hotel should not be directed towards rooms and black outcurtains must be used. Additionally, eye masks may be madeavailable in hotel rooms.

During day-time a lack of daylight may cause seasonal affectivedisorders. For this reason, the hotel rooms, restaurants and otherfacilities of the hotel should get as much daylight as possible, toallow more amount of the secretion of serotonin, during the day(Kripke, 1998; Stain-Malmgrem, Kjellman, & Aberg-Wıstedt, 1998).If this is not possible, artificial lighting could be used. Hotel man-agement are also recommended to take the ages of the guests intoaccount, as the amount production of melatonin varies with age(See Fig. 1).

The circadian rhythm of people may change with the changingof work shifts too. Especially in all-inclusive hotels where many ofthe services (e.g. food and beverage services) are provided on analmost non-stop and continuous manner, the hotel managementshould be careful about changing work shifts. Changing work shiftsof the employees in the middle of the peak season may causeemployees to get easily depressed and become aggressive. Thedepressed and aggressive employees may cause many service fail-ures in their encounters with tourists, especially with those touristswho are suffering from the jet lag.

Moreover, the hotel management may be recommended toprovide food items that are rich in melatonin (Paredes et al., 2009)so as to reduce the changes relating to the circadian rhythm andphotoperiod of their guests and employees (See Table 2).

2.4. Emotions and moods

Many research studies show that emotions and moods canplay important roles on customer satisfaction evaluations andjudgements (Andreassen & Lindestad, 1993; Athanassopoulor,Gounaris, & Stathakopoulos, 2001; Bagozzi, Gopinath, & Nyer,1999; Bloemer & de Ruyter, 1998; de Rojas & Camarero, 2008;Stauss & Neuhaus, 1997; Vogt & Fesenmaier, 1998; Yuksel, 2007;Yuksel & Yuksel, 2007), especially in hospitality services inwhich customer-personnel interaction is relatively high. The roleplayed by emotions and moods is not overt, nor apparent andhence, it is not an easy task to detect them from the outside.Moreover, emotions and moods are subjective states and it is noteasy to quantify and examine them with objective methods. Forthis reason, research on emotions and moods has largely been

neglected (Hanoch, 2002) over the past few decades with ex-ceptions of a few studies. The contribution of such seminal workssuch as Kahneman and Tversky’s (1979) Prospect Theory, Averill’s(1973) Control Theory and Langer’s (1975) Illusion of Control,Damasio’s (1994) Somatic Marker’s Hypothesis can never beoveremphasized in understanding the role of emotions againstrational decision making. Today, with the developments ofmedical imaging techniques such as electroencephalography(EEG), Magnetic Resonance Imaging Instrument (MRI Scanner),Functional Magnetic Resonance Imaging Instrument (fMRI Scan-ner), Positron Emission Tomography (PET) and Electromyography(EMG), it has become possible physically to explore the pre-cursors of human behaviour.

Emotions are tendencies to establish, maintain, or disrupt arelationship with the environment. In other words emotions maybe defined as action readiness in response to emergencies or in-terruptions (Frijda, 1987). Emotions regulate and guide humanbehaviour through their biological, social, and cognitive compo-nents. Emotions are not only experienced but they are also reactedto. The physiological reactions involve changes in the autonomicnervous system, whichmay be the basis for the ‘feeling’ of emotion.Alternatively this feeling may be based around specific areas of thebrain, which in turn control physiological responses of humanbeings (Gorman, 2004).

Emotions, and moods, can be classified as positive and negativeones. However, research shows that in addition to this basic clas-sification or typology, many other classifications or typologies ofemotions can be made (Diener, Diener, & Diener, 1995; Shaver,Schwartz, Kirson, & O’Conner, 1987). Classifications or typologiesof main emotions usually comprises of five to ten emotions, such asfear, anger, sadness, disgust, joy, and love (Plutchik, 1994).

The limbic system (responsible for emotions) in human brain islarger than the frontal cortex (i.e. responsible for rational pro-cesses). Human brain has a more tendency to make emotionalprocessing rather than rational processing (Amaral, Price, Pitkanen,& Carmichael, 1992; Baker, Greenberg, & Hemingway, 2006;

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McDonald, 1998). Moreover, the number signals from the limbicsystem (emotional part of the brain) to the frontal cortex (rationalpart of the brain) are ten timesmore than the vice versa (Hawkins &Blakeslee, 2004). It was explained above that impulse purchases,emotional responses in a purchase situation, may constitute of upto 95% of all purchases.

The term “affect” is broad in nature and comprises two relativelydistinct phenomena of emotions and moods. Moods tend to belonger lasting but often weaker states of uncertain origin, whileemotions are often more intense, more short lived, and have a clearobject or cause (Frijda, 1993). For instance, one may be in agenerally sad or happy mood all morning for no particular reason,or one may feel strongly angry at someone during a quarrel in theafternoon (emotion). Moods tend to be conceptualized as havingtwo dimensions. Depending on how the dimensions are rotated,they can be labelled hedonic tone/pleasantness and arousal/acti-vation (Larsen & Diener, 1992; Russell, 1980), or positive affect andnegative affect (Watson & Tellegen, 1985).

As explained above moods are less intense, longer lasting andare largely unintentional in that they may occur in the absence of arelevant object. They also incorporate some element of cognitiveprocessing or are ‘moderately mediated’ by cognition. Moodsmainly express the subject’s own situation, and in this sense aresimilar to feelings. However, subjecteobject relationships, whichare crucial to emotions, are of lesser importance to moods. Moodsdiffer from emotions in the sense that they are generally are of lessintensity and longer-lasting than are emotions. Moods and emo-tions also differ in terms of their causes. Emotions are mainlyactivated by events and changes in the social environment that aresudden and urgent, but moods are less specifically tied to an elic-iting situation and are ordinarily lacking in urgency (TenHouten,2007). Table 3 summarizes the main characteristics of emotionsand moods (Bagozzi et al., 1999).

Research shows that when customers are in good mood, theytend to stay more in the service establishment, spend more timeand make more purchases (Alpert & Alpert 1990; Bitner, 1992;Spies, Pau, & Yang, 1997; Swinyard, 1993). Babin, Griffin, andBoles’s (2004) research shows that strong positive moods orfeeling states such as “good,” “happy,” “satisfied,” and “wonderful”can lead to an increase in time spent in the service establishment,an increase in the amount of spending, and an increase in judge-ments of liking for the service establishment.

Findings of various research studies show that moods and be-haviours have some consistent patterns. There is congruence be-tween mood states and judgements of services (Gardner 1985).When customers are in a positive mood they tend to make moreoptimistic judgements about evaluations and expectations thanthose customers in negative moods (Forgas, 1995; Hsu & Liu, 1998).According to Prakash and Hutchinson (1984) when customers arein a positive mood they become more satisfied than they are ineither neutral or negative moods. Research also shows that there isa positive relationship between positive mood, satisfaction andloyalty (White & Yu, 2005).

Mood is generally associated with neurotransmitters and foodintake. A variety of foods may affect mood and health. According to

Table 3A summary of the main characteristics of emotions and moods.

Emotions Moods

Duration Last Shorter Last LongerIntensity Higher LowerIntention Intentional Non-IntentionalAction Tendency Direct and Explicit Indirect and Implicit

Source: Bagozzi et al. (1999).

Prasad (1998) many patients e diagnosed with conditions with asignificant depressive component such as seasonal affective disor-der (or winter depression), premenstrual stress syndrome, ornicotine withdrawal e consume large quantities of carbohydrate-rich food to elevate their mood. Consumption of carbohydrate-rich food may elevate mood in such individuals by raising brainserotonin levels. As mentioned above a meal high in carbohydrateincreased the rate that tryptophan enters the brain, leading to anincrease in the level of the neurotransmitter serotonin that mod-ulates mood (Benton & Donohoe, 1999).

Depressive disorders such as depression, melancholy, seasonalaffective disorders constitute more than one fourth of all healthproblems in theworld. It is estimated that after 2020 the depressivedisorders will be the second most prevalent health problem in theworld (Lecrubier, 2001; Murray & Lopez, 1996).

Based on the above explanations relating to emotional disordersmanagers of hospitality businesses are recommended to designtheir service offerings, e.g. their servicescapes, in such a way tocreate positive emotions and moods for their customers. Addi-tionally, mood enhancing foods and beverages (see above), thephysical design of the facilities of the hospitality establishment (e.g.using soft colours, freshly cut flowers in terms of both appearanceand their smells; ergonomically designed furniture’s; and calmingmusic may create positive emotions and moods). One of the mainmotivations of tourism is to put back, i.e. a kind of balancing act,what daily hectic life takes away from individuals (Koc, 2013b).Stress in dailye ordinary lifee can be a huge drain on the serotoninreserves. As mentioned above serotonin as one of the mostimportant neurotransmitters influences people’s happiness, levelsof energy and their cognitive abilities. Tourists may increase theirserotonin levels on holidays which have been purposefullydesigned, i.e. to put back what ordinary life has taken away fromthem.

3. Conclusion

The study suggests a unique approach to consumer/touristbehaviour called psychoneurobiochemistry. This pioneering pre-liminary study is an attempt to explore and relate some of thepotentially relevant studies in psychology, neurology, biology andchemistry to tourism marketing. As this is a preliminary study onlya few of the perspectives have been analysed and synthesized. It isseen that psychoneurobiochemistry has significant potential impli-cations for the tourism and hospitality sectors. The practitioners inthese sectors may and can design their offerings better by makingenhancements on their 7 P s (tourism and hospitality product,price, place, promotion, physical evidences, processes and people)as explained above and hence increase their customer satisfactionand loyalty. Increasing customer satisfaction and loyalty may pro-duce a number of positive outcomes such as increased profits anddecreased costs.

However, as mentioned above this is a preliminary study, and itmust be borne in mind that there is need for further analysis andsynthesis of research studies in above disciplines from theperspective of tourism and consumer behaviour. It must also beremembered that there are ethical repercussions of the matter.The practitioners should not see research findings in the field ofpsychoneurobiochemistry as a means to establish customercaptivity.

The managers of tourism and hospitality establishments arerecommended to follow the recommendations offered, as they areoperating in a highly competitive and fast changing market. Themove from General Interest Tourism (GIT) to Special InterestTourism (SIT) alone is enough reason to urge managers to takepsychoneurobiochemistry of tourism into account.

E. Koc, H. Boz / Tourism Management 44 (2014) 140e148146

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Dr Erdogan Koc is professor of marketing at BalikesirUniversity, Bandirma Faculty of Economics and Adminis-trative Sciences, Turkey. He is the chair and head ofdepartment of business administration. He has writtenseveral journal articles and book chapters published byinternationally reputable publishers. He serves on theeditorial boards of a number of journals and has acted asan ad hoc referee for more than fifteen respectable jour-nals. His research primarily focuses on the human element(both as consumer and employee) in tourism and hospi-tality. He provides consultancy and training services forthe service sector businesses.

Mr Hakan Boz is lecturer at Usak University’s School ofApplied Sciences. Prior to joining the academia he has heldvarious positions in the tourism and hospitality sectorbusiness. He has over ten years of experience in thesesectors. He carries out research to better understandconsumer and employee behaviour in the tourism andhospitality sectors, especially by using equipments such asEEG and fMRI together with Professor Erdogan Koc.