Motivation and emotion/Book/2013/Cannabis and emotion
What is the effect of cannabis on emotion?
This chapter focuses on the effects of cannabis on emotions. It is worth noting that the information provided in this chapter is purely to educate individuals on what psychologically research and theory has found on the topic, and not as a means of professional advice or treatment. Firstly, the chapter will examine background information on cannabis, such as the prevalence rates in Australia, America, and worldwide. Additionally, a brief explanation of cannabis and the effects on the brain is provided. Followed by, the psychological theories on the motivation behind cannabis use.Finally, the effects of cannabis on emotions, specifically anxiety, depression and psychosis are outlined. The chapter will conclude with a brief examination of the most successful treatment options, according to psychological research.
What is cannabis?
Cannabis is a plant derived from Cannabis Sativa, it can be smoked by drying buds of the plant, which is a common method, and it can also be eaten, or taken in a water pipe, known as a bong (Hall & Solowij, 1998).Cannabis is also known as “marijuana”, “grass”, “pot”, “dope”, “Mary Jane”, “weed”, “hash”, “joints”, “cones”, “smoke”, but the most common name for cannabis is Marijuana (Hall & Solowij, 1998; McLaren & Mattick, 2010; Green, Kavanagh, Young, 2003). Cannabis contains over 60 cannabinoids, which provide the psychoactive effects (McLaren & Mattick, 2010). The main ingredient in cannabis is called the delta-9-tetrahydrocannabinol (THC), which is what gives individuals the sensation of feeling “high” (Hall & Solowij, 1998). Cannabis utilises its psychoactive effects via endogenous cannabinoid receptors in the brain, which are areas that control movement, appetite, emotion, and cognition functioning (Hall & Solowij, 1998). Desirable effects of cannabis intoxication include relaxation, enhanced sensory experiences, increased sociability, and undesirable effects such as anxiety, panic attacks and paranoia (Hall & Solowij, 1998; Ameri,1999).
Cannabis is the most widely used illicit drug in Australia and worldwide. It has been estimated that 141 million (2.5%) of the world’s population use cannabis (Green, Kavanagh & Young, 2003). According to the Australian Health and Welfare (2006), one in three people (34%) have used cannabis at least once in their lifetime, and 11% of the population have used cannabis in the past year. A more recent National Drug and Strategy Household Survey (2010) in Australia revealed that individuals who reported using cannabis in the past year, 16% of them use it every day, and over half use it less than monthly (McLaren & Mattick, 2010). Additionally, cannabis use is more commonly used by individuals in their early 20s, and more commonly used by males than females (Swift, Hall & Teesson, 2001). In terms of comparing cannabis use in Australia and other countries, it has been found that USA, Australia, and UK have similar prevalence rates, approximately 11%, Canada and New Zealand have higher annual prevalence rates 14%-20%, and the rest of the world’s prevalence rates are usually under 10% (McLaren & Mattick, 2010).
Short-term and long-term effects
(Hall & Solowij, 1998)
(Hall & Solowij, 1998)
Psychological theories on drug/cannabis use
It is important to examine why certain individuals take drugs, or in particularly start using cannabis, while other individuals would never imagine taking any type of drug. Psychologists have examined and tested theories to explain the motivation behind drug use. Although past literature has found many theories in hopes of explaining the motivation behind consuming drugs, the three main theories that this chapter will focus on is the Planned-Behaviour Theory, Problem-Behaviour Theory and Emotional Distress Model.
The Theory of Planned-Behaviour (TPB) was proposed by Ajzen (1985, 1987) and examines factors that determine decisions to adopt or maintain a particular behaviour (Conner & McMillan, 1999). The determinants of an individual’s behaviour is through behavioural intentions (what the person plans to do), and the behaviour of an individual is achieved through influencing the individuals intentions (Petraitis, Flay & Miller, 1995). TPB claims that there are three factors determinant of an individual’s behaviour:
- The attitude towards behaviour
- Subjective norms
- Perceived behavioural control
Firstly, is the attitude towards the behaviour, the attitude is based on the individual’s beliefs about the outcome of the behaviour, which is based upon assessing each outcome and the likelihood that the performance of that behaviour will lead to that particular outcome (Conner & McMillan, 1999).Secondly, is the subjective norms/social pressure to perform that particular behaviour, determined by normative beliefs which specific groups hold towards the behaviour, and the motivation to abide with each of the groups, influences intentions (Conner & McMillan, 1999). Thirdly, is the perceived behavioural control the individual has over the behaviour, which influences intentions to perform the behaviour (Conner & McMillan, 1999). The perceived behavioural control factor is used to predict both behavioural intention and, if the individual believes that they have high levels of control over the behaviour, it will also predict the problem-behaviour (Ajzen, 1988 Cited in Conner & McMillan, 1990).
Several studies have found empirical evidence for TPB being a predictor of health behaviours (Conner & McMillan, 1999; Ajzen, Timko & White, 1982; Armitage, Armitage, Conner, Loach & Willetts, 1999). A study on cannabis use was conducted by Connor & McMillan (1999) using TPB, and found that intentions were predicted by attitude, subjective norms and perceived behavioural control; however behaviour was predicted by intentions, not perceived behavioural control. Additionally, other studies examining TPB on cannabis use also found results supporting TPB as a predictor for cannabis use (Ajzen, Timko & White, 1982; Armitage, Armitage, Conner, Loach & Willetts, 1999).
The Problem-Behaviour Theory was first proposed by Jessor and Jessor (1977), suggesting that behaviour such as drinking, marijuana use, delinquent behaviour, and sexual intercourse may well constitute a "syndrome" of problem behaviour in adolescence (Donovan & Jessor, 1985). The “syndrome” of problem behaviour in adolescence, emerged from Jessor’s analyses of data from two longitudinal studies of high school students and college students (Donovan & Jessor, 1985). In these studies, problem behaviours were found to be positively associated with personality and environment variables that reflect the framework of problem-behaviour theory (Donovan & Jessor, 1985). According to the problem-behaviour theory, cannabis use, drinking or problem drinking, illicit drug use, sexual intercourse and certain delinquent behaviours are considered negative behaviours for adolescents, and thus committing these behaviours can represent a transition in a psychosocial development, or a more mature status (Jessor, Chase & Donovan, 1980). The occurrence of a problem in the problem-behaviour theory is determined by three system variables, the personality system, the perceived environment system, and the behaviour system, and within each of the three systems is specified by the likelihood of the problem behaviour occurring (Jessor, Chase & Donovan, 1980).
The personality system refers to attitudes, values, beliefs and expectations that establish the willingness to engage in the problem behaviour (Petraitis, Flay & Miller, 1995).
The environment system refers to perceptions of low supports and control from significant others, and approval from individuals or groups engaging in problem behaviour (Petraitis, Flay & Miller, 1995). Environment systems variables include great influence from friends than parents, greater perceived approval and pressure from individuals or groups involved in the problem behaviour, increase the occurrence of the behaviour (Jessor, Chase & Donovan, 1980).
Finally, the behaviour system refers to the degree of involvement in other problem behaviours. The greater degree of personality, perceived environment and behaviours systems is, the greater the expected involvements in problem behaviours, such as marijuana use (Jessor, Chase & Donovan, 1980).
Emotional distress model
The past two theories explain intentions and behaviours influenced by the individual's environment, intentions, beliefs, attitudes and peer associations, however overlooks the individuals ability to cope with everyday stress. Therefore, it is important to examine stress as a predictor for substance abuse. Emotional distress models postulate that individuals who are emotionally distressed, or distressed in general, either through anxiety, depression or some form of psychological pain will try to eliminate this pain through the use of drugs (Russel & Mehrabian, 2007 Cited in Sinha, 2001). Several studies indicate that cannabis is used as a stress coping strategy (Boys, Marsden & Strang, 2001; Hataway, 2003; Brodbeck, Matter, Page & Moggi, 2007; Lee, Neighbors & Woods, 2007). Stressful events such as family dysfunction, negative life events and traumatic stress are all associated with cannabis consumption. A study conducted by Hathaway (2003) examining long term cannabis users, found that these cannabis users reported “relaxation” as being the most important reason, following as a coping mechanism, or coping motives. To further illustrate, Boys, Marsden and Strang (2001) studied long-term cannabis users between the ages of 16 and 22 years, and found that 97% of those individuals reported using cannabis as a strategy to relax, 69% reported using cannabis when feeling “down” or “depressed”, and 58% used cannabis when in need of a quick fix to their problems or worries.
Given the literature supporting stress and cannabis use, it appears that stressful life circumstances can increase cannabis use, more severe addiction, greater distress and poorer mental health (Brodbeck, Matter, Page, & Moggi, 2007).
The effects of cannabis on emotions
Studies have recently examined whether cannabis causes schizophrenia or schizophrenic symptoms. A study conducted in Sweden analysing a large population of 50,000 men, suggested that those individuals who used cannabis more than fifty times before the age of 18, had greater increased risk of developing schizophrenia later in life (Zammit, Allebeck, Andreasson, Lundberg, & Lewis, 2002). Although this study found a small significant relationship, it has been argued that cannabis may cause schizophrenic illness a lot earlier in vulnerable people who display schizophrenic tendencies, as opposed to non-users. To illustrate this point, a study was conducted on newly admitted schizophrenia patients, found that patients who used cannabis, experienced their first psychotic episode 6.9 years earlier, than the schizophrenia patients who never used cannabis (Veen, Selten, Van Der Tweel, Feller, Hoek & Kahn, 2004). Furthermore, high doses of cannabis may produce psychotic symptoms such as hallucinations, delusions, disorientation, depersonalisation and paranoia (Thomas, 1996; Van Os, Bak, Hanssen, Bijl, De Graaf, & Verdoux, 2002) however, in many of these cases the psychotic symptoms recovered rapidly after abstinence from cannabis. It is likely that high dose of cannabis may exhibit psychotic symptoms, but as mentioned earlier symptoms recover after abstinence. Therefore, there is not enough substantial evidence to conclude that cannabis can cause psychiatric illness in those individuals who have not previously had psychotic symptoms (Hall & Degenhardt, 2000).
It has been suggested that long-term cannabis use can increase anxiety, panic attacks and anxiety disorders (Fusar-Poli, Crippa, Bhattacharyya, Borgwardt, Allen, Martin-Santos & McGuire, 2009; Iversen, 2005). However, short term cannabis use has been associated with decreasing anxiety symptoms, increasing sedation and relaxation (Fusar-Poli et al., 2009). Individuals with psychotic illnesses report using cannabis as a mechanism to cope, reduce their anxiety associated with their psychotic symptoms, and increase positive moods (Lee, Neighbors & Woods, 2007). Studies examining motivation behind cannabis use found that relaxation was the most reported reason (Boys et al., 2001; Green, Kavanagh & Young, 2003; Hathaway, 2003; ). This conflicting evidence can be explained through the multiple compounds that cannabis contains, which have different psychoactive properties, such as the Tetrahydrocannabinol (9-THC) and Cannabidiol (CBD), which both reduce anxiety (Fusar-Poli et al., 2009). An instant administration of 9-THC increases anxiety, but also can reduces anxiety and improves sleep (Fusar-Poli et al., 2009).
Researchers have examined whether cannabis use causes depression later in life. Studies examining cannabis use within adolescence found that early onset of regular cannabis use increased the risk of developing depression, or depressive disorders later in life (Brook, Brook, Zhang, Cohen & Whiteman, 2002; Fergusson & Horwood, 2001). Brook et al. (2002) found that early onset of cannabis use (childhood, adolescence) increased the risk of major depressive disorder by 1.17 times more than those individuals who did not. Additionally, Fergusson & Horwood (2001) tested the association between heavy cannabis use during adolescence, depression and suicide. Their study found that by the age of 20-21 years, the 30% of the individuals who reported using cannabis weekly or more, met criteria for depression, compared to 15% who did not use cannabis. A study examining the relationship between cannabis and depression in adulthood found that the participants who reported using cannabis and at least one symptom of cannabis dependence were 4.5 times more likely to report depressive symptoms and 4.6 times more likely to report suicide ideation compared to individuals who were non-abusers of cannabis (Bovasso, 2001).
Demand for cannabis dependence treatment has increased in Australia over the past 15 years (Budney, Moore, Rocha & Higgins, 2006; Nordstrom & Levin, 2007). Cannabis dependence treatment methods include simple screenings, interventions, multi-session psychotherapy treatment, or pharmacotherapy (Budney et al., 2006). The two major psychotherapy treatments that have proven to reduce cannabis dependence are Cognitive Behavioural Therapy (CBT) and Motivational Enhancement Therapy (MET) (Norstrom et al., 2007; Copeland, Swift, Roffman & Stephens, 2001). CBT focuses on coping skills to deal with situations in which cannabis use is most likely to occur, and MET focuses on motivational interviewing (Norstrom et al., 2007). CBT and MET have been tested on sample populations seeking cannabis abuse related treatment, and have both resulted in effective treatment outcomes (Budney & Moore, 2002; Budney, Higgins, Radonovich & Novy, 2000; Copeland et al., 2001). However, limited amount of studies have been conducted to test treatments for cannabis abuse or dependence, compared to other drugs such as heroin (Budney et al., 2006) as cannabis dependence is less reported by users, as opposed to other drugs.
Cannabis is the most utilised drug worldwide, by adolescence in early 20s, and most commonly taken by males than females. The most common reason for cannabis use is for relaxation purposes, as a stress coping mechanism, and for decreasing anxiety. However, long term exposure to cannabis has been reported to increase anxiety and paranoia, as well as psychotic symptoms, increased risk of respiratory diseases, decreased memory and learning abilities, and decreased motivation and concentration. In addition, short-term effects include relaxation, talkativeness, paranoia, appetite increase, loss of co-ordination, dry mouth, eyes and throat. Individuals who a vulnerable to psychosis have a increased chance of developing schizophrenia earlier in life compared to schizophrenia vulnerable individuals who do not use cannabis. Additionally, regular cannabis use has also been associated with increased risk of developing depression, or depressive disorders. Individuals who develop a cannabis dependence may receive psychotherapy as treatment. The most beneficial psychotherapy treatments are Cognitive Behavioural Therapy (CBT) and Motivational Enhancement Therapy (MET), as they have been proven to reduce cannabis dependence. Considering that cannabis is the most widely used drug among adolescence, it is important for individuals to be educated about the negative long-term emotional and physical effects cannabis can cause.
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