The Dummies Guide to the Biological Approach

The Dummies Guide to the Biological approach

Summary

Definition and key CNS, neurotransmitter, nature-nurture, hormones, evolution, genes, aggression, addiction,
terms
Methodology PET, MRI, fMRI, twin and adoption studies, correlations
Content CNS and synaptic transmission, neurtotransmitters and hormones, effect of drugs on CNS, brain
structure and function, evolution, psychodynamic and aggression,
Theories of Biochemical theory of aggression (hormones and neurotransmitters)
aggression Evolutionary theory of aggression (genes)
Psychodynamic theory of aggression (emotions)
Two studies in Raine et al (97)-Brain abnormalities in murderers
detail Brendgen et al (2005) twin study on genetic and environmental effects on social aggression
Minor studies to Cadoret & stewart (91) – adoption studies
support method Olds & Milner – drugs and CNS - animal study
and/or theory
Key Question What are the implications for society if aggression is found to be caused by nature not nurture?
Practical Correlation study to see if there is a relationship between length of ring finger and a self rating
of aggressive tendencies, spearmans Rho test

Key assumptions

1) The importance of genetic influences on behaviour:
The physiological approach see us as being to a large extent who and what we are by
the genes inherited from our parents. We inherit 50% of our genes from our mother and
50% from our father. The more closely related two people are the more likely they will share the same characteristics (e.g. IQ,
height, schizophrenia etc). A person has their ‘nature’ which is given to them by their genes, and a ‘nurture’ which is given to them
by their environment.

2) The role of neurotransmitters on behaviour:
The central nervous system consists of our brain and spinal cord. The automatic nervous system (ANS) which controls functions of
the body such as the heart, lungs etc, which we have no conscious control. The Peripheral nervous system (PNS) controls those
parts of the body to which we have conscious control such as flexing muscles. The brain guides behaviour through neurotransmitter
functioning.

3) Brain Structure and behaviour:
The brain has many parts, hippocampus is thought to be where STM occurs, and the hypothalamus produces hormones that
influences gender during pregnancy. The brain is in 2 halves, joined by a mass of bundles called the corpus callosum. Brain
lateralisation is the term used for considering the two halves of the brain separately and studies have shown that males and
females use these hemispheres differently.

2. BIOCHEMICAL THEORY OF AGGRESSION – The role of neurotransmitters and
hormones

THE CENTRAL NERVOUS SYSTEM
The CNS consists of the brain and the spinal cord. Our nervous system is activated
when we receive a stimulus from the environment and respond to it, the messages
are transmitted by a series of electrical impulses through nerve cells.
Neurotransmitters are chemical messengers that travel in the brain between
neurons. Motor neurons receive messages from the CNS, sensory neurons transmit
messages from the senses.

 An electrical impulse travels down the axon to the terminal button
 Vesicles containing neruotrasmitters are realesed into the synaptic gap

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 The receptors on the nearby dendrite receives the neurotransmitter if it ‘fits’ or not. (lock and key)
 If it is not taken up the message is stopped
 If it is taken up the message continues to travel down that neuron’s axon so the message continues.
 Neurotransmitters that are not used are recycled (reuptake) beck into the pre-synapse

Dopamine – linked to addiction , associated with pleasure
Serotonin – regulates sleep-wake cycle. Low levels linked to depression
GABA – acts as an inhibitor to block messages, helps to calm nerves
Norepineprine – prepares for fight or flight
Acetylcholine – memory and thinking, associated with Alzheimers
Glutamate – cognitive functioning and brain decelopment. Too much can lead to stroke

THE EFFECT OF TRANSMISSION OF DRUGS ON THE CNS
Agonists – bind to receptors and stimulate them to increase the messages (eg Cocaine, heorin,
morphine, nicotine)
Antagonists – bind but don’t stimulate receptors instead they reverse or deactivate the effect of agonists (beta blockers, mathadone,
naloxone)
Mode of action - There are 3 ways that drugs interfere with the processes at the synapse

 Block receptors so that neurotrasmitters cant fit into them (Antagonist - canabis)
 Attach to receptors and mimic the effect of neurotransmitters (Agonist- nicotine)
 Prevent recycling of neurotransmitters so that they stay in the synapse and reattach to receptor cells (Agonist - cocaine)
Nicotine – mimics acetycholine and binds to ACTH receptors which excites neuron to release dopamine. Over time causes decrease in
dopamine receptors, to get a’normal’ level more dopamine is needed which leads to addiction.
Cocaine – blocks binding site of reuptake causing excess dopamine in the synapse leading to over stimulation on recpetor sites. This
affect eventually damages the receptor sites reducing the amount meaning more cocaine is needed to maintain a ‘normal’ level.
Canabis – Binds to receptors and blocks activity, especially in the hippocampus area which affects memory. Dopamine is still released,
canabis removes the inhibiting affect of GABA so dopamine neurons can be released. Damage to the receptors reduces blood flow and
osxygen to the brain.

STRENGTH: Olds and Milner (54) – rats will press a lever to get electrical stimulation to the pleasure centre rather than get food or drink.
They will even risk crossing and electrical grid to receive the stimulation.
WEAKNESS: the brain is very complex, there is more than one pathway in the reward system, there are lots of neruotransmitters and
brain areas working simultaneously to claim X causes Y to happen.
Stuyding mode of action is diffcult, but helped by brain scans.
Not always possible to extrapolate results from animal studies as there may be differences in functioning although more ethical

ROLE OF HORMONES IN AGGRESSION
Hormones are also chemical messengers but travel via the bloodstream. They work by binding to receptor proteins and changing cell
function. Behaviour is affected on when they are released, the concentration level and how they are received at cell level. The
enironment also has an influence on hormone release, such as a stessful situation.
Testosterone is a male sex hormone secreted by the adrenal glands and testes. It is needed to produce sperm, develop male
reproductive organs, facial hair and deep voice. Women also have tesosterone but males produce 10mg a dat which is 10 times more
than women.
Dabbs et al (87) measured saliva of 89 male prisoners and found 10 out of 11 prisoners with high levels of tesosterone were involved in
violent crime.
Barzman et al (2013) measured slaiva samples of 17 boys in a psychiatric hospital (aged 7-9) and aggression was recorded by
observation of aggressive behaviour. They found that the amount of cortisol 30 mins after waking up correlated with the number of
aggressice incidents
Strength: Injecting animals with tesosterone or removing (castration) the testes leads to increased or decreased levels of aggression.
However if the same animal is then injected with tesosterone the aggression level is restored to a similar level before the castration.
Suggests a clear cause and effect relationship.
Strength: There are so many studyies using different methods and measures on both animal and humans that give sicentific credibiity to
the findings. Suggesting reliability in a correlation between testosterone and aggression.
Weakness: Aggression in humans is lesss instinctive than animals so difficult to compare between animal and human studies.
Weakness: Blood tests can measure the level of tesosterone but not all humans with high tesosterone are aggressive and some women
are more violent than men.
Weakness: This explanation completely ignores the social circumstances on our behaviour.

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BRAIN STRUCTURE AND AGGRESSION

The brain is made up of different structures. 4 lobes (temporal, parietal, occipital and prefrontal).
Lateralisation – 2 halves of the brain connected with a large bundle of fibres called (corpus
callosum) if this is split, eg severe epilespy, then the individual cannot link messages between the
left and right hemispheres. (Sperry 50)

Damage to the pre-frontal lobe is linked to aggression. Eg Phinneous gage. PET, MRI and fMRI are
methods used to find out which parts of the brain are associated with aggression.
Pre-frontal cortex also associated with depression. PET scans suggest that the lower the activity in
the region the more likely there will be depression. The limbic system and amygdala is also implicated
The Limbic system

• The limbic system is a set of brain structures that lies in the middle.of the brain. It looks a
bit like a wishbone It is called the ‘emotional area’ of the brain because it is responsible
for emotion needed for survival, like fear and aggression

• People with emotional disorders have been shown to have had damage to the limbic
system, the system jointly responsible for recognising, controlling and producing
aggression, but some research has focused on the amygdala.

The amygdala
 The amygdale is a structure in the brain that recognises emotion. If someone smiles we
know they are happy, and if they frown we know they are sad. The Amygdala also creates emotional responses. You have
probably seen a frightened cat; it bares its teeth and hunches its back. This is the amygdala producing the fear response.
 The amygdala is also responsible for producing aggression. In animal studies, if the amygdala is removed the animal becomes
very calm and does not respond to threatening situations with aggression. Damage to this area of the brain may cause
increased levels of aggression.

 Swantje et al (2012) – conducted MRI scans on 20 right handed women to measure the size of the amygdala. They were also

asked to complete a Life History of Aggression Assessment. They were screen for psychiatric disorders etc. They all had a
normal range in lifetime aggression score. Those with a high score had a lower volume of amygdala by 16-18% showing a
significant negative correlation in that the more lifetime aggression the small the volum of amygdala.
 Andy & Velamati (78) - stimulated the limbic system of cats which resulting in aggressive seizures. (Measured by the amounts
of howling and hissing)

METHODOLOGY

PET AND MRI SCANNING TECHNIQUES
PET scans involve producing computer generated pictures of the brain. A radioactive tracer is
injected that emits a signal that can be picked up and formed into a picture of how much
tracer is absorbed by the area of the brain that is functioning. The PET scan measures blood
flow and oxygen/glucose use.
MRI Scans is a technique that use magnetic and radio waves that pass through the body when
the person lies in the large cylinder. The scanner picks up signals of the body’s atoms move back into positron and the computer
turns the signals into a picture.

Strengths: Non-invasive, scans are accurate, reliable, fMRI gives clearer pictures than MRI and PET scans. Brain structures can be
isolated and measured which are reliable. The person is alive!
Weakness: Expensive, care must be taken to interpret the results. PET scans don’t show a fine image, ethical issue of injecting
radioactive substance. Questions valdity because processing is likely to be artifical. Eg Scott and smoking.

RAINE 1997
Aims: Wanted to find out about brain differences between murderers pleading NGRI and non-murderers.
Sample and Design: 41 murderers charged with manslaughter. 23 had history of brain damage, 6 with schizophrenia, 3 with substance
abuse, 2 with mood disorder, 2 with epilepsy , 3 with learning disability and 2 with paranoid personality.
The control group was matched for these features. The study took place in a University in USA.
IV = whether participant was a murderer or not
DV = various measures of brain activity
Procedure: Each PPt carried out a practice test and then injected with a trace, then given more tests. After ½ hr a PET scan was taken.
Slices of the scan were checked for glucose levels and compared with the controls.
Results: murderers had lower glucose metabolism in some prefrontal areas. There were no differences in the temporal lobe. The
murderers had lower glucose in the corpus callosum and had different levels of activity in the area of the brain linked to aggression.

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Conclusions: murderers have lower glucose activity levels and abnormal activity in other areas. Suggest biological cause. Could not
conclude biological cause for violence just a predisposition for it depending on the environmental triggers (nurture).
Strengths: PET scanning is objective and results can be interpreted by more than one person making it reliable. Sample size is large
enough for generalisation to murderers pleading NGRI.
Weakness: there were no violent criminals in control group so hard to generalise beyond study. Does not show biological causes for
violence because environment can cause brain differences.

2. EVOLUTIONARY THEORY OF AGGRESSION The importance of genetic influences on behaviour:

We inherit genes from our parents and any characteristics that enable an individual to survive and reproduce are likely to be passed to
the next generation. Evolution is how the inherited characteristics change over time, any characteristic that doesn’t enhance survival
will die out. (survival of the fittest).

 Variation – all life forms vary genetically within a population. It is this genetic variation upon which selection works. (Height)
 Inheritance – genetic traits are inherited from parents and passed on to offspring, there is an element of chance of which genes

are passed on which means some genes are lost.
 Selection – organisms with traits that are favourable to their survival get to live and pass on their genes to the next generation

(altruism the individual risks their own lives to save others in their kin)
 Time – evolution takes time. Evolution can happen in a few generations, but major changes often takes longer

TWIN AND ADOPTION STUDIES

TWINS
MZ = share 100% genes and are identical as they come from the same fertilized egg and are normally
the same gender.
DZ = share 50% genes, non identical (fraternal) as they come from different eggs and can be different
genders.
If genes are a factor (nature) then we should expect a high proportion of identical twins to share
the same disorder.
If a characteristic (aggression, alcoholism, depression etc) is due to genes then MZ twins should share
that characteristic.
A psychologist can use twin studies in two ways;

 Either comparing MZ with DZ OR Comparing MZ twins reared apart with those reared together.
When you look at MZ twins reared apart you have isolated the variable of genetic influence because they have identical genetic make
up but differing environments.
Strengths:

 there is no other way to study genetic influences clearly, MZ and DZ share same environment so there is a natural control over
environmental effects

 Produced a great deal of data to support biological arguments for causes of mental health problems enabling psychologists to
find biological ways of helping people

Weaknesses:
 MZ have identical DNA but they may gown and develop differently due to environmental influences. (Nature/nurture).
 MZ are normally treated the same by parents and others so environment may not be as controlled as may be thought
 MZ twins are rarely separated from birth and raised in a totally different environment. This is really what is required to make
the claims of the researchers truly valid.

ADOPTION
Looking at children who are adopted and then comparing their characteristics with their biological and adoptive parents. If a child
develops depression and the biological parents also have depression but not the adoptive parent then it can be argued that the
characteristic has been inherited through the genes.
With regard to adoption studies we conduct the correlation on:-

 Adopted child and biological mother
 Adopted child and adoptive mother
Cadoret & stewart (91) found the adopted boys were at an increased risk of
ADHD/hyperactivity and aggression as children if they had a biological parent who had
been convicted of a crime in adulthood. They also found that the boys were more likely
to be aggressive or have a diagnosis of ADHD if there were psychiatric problems in

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members of the adoptive family. This suggests that behaviour as complex as aggression can have a variety of causes and is not
significantly attributable to nature or nurture.

Strengths:
 They control for the environment because children do not share the same environment as their biological parents and therefore

isolated the environmental factors.
 Studies can be longitudinal so any trends can be studied.
Weakness:
 Families that adopt are similar to each other so there may be something in that similarity. Because they are chosen for similarity

the environment and upbringing may not be very different.
 It is rare to be adopted immediately after birth and so the child would have spent time with their biological family initially meaning

there are possible confounding variables.

BRENDGEN ET AL (2005) – TWIN STUDY
Aims: To examine the correlation of social and physical aggression of 6yr old twins

To investigate the causal mechanisms to explain the positive correlation
Sample and design: 234 6yr old twins. MZ: 44M/50F, DZ: 41M/32F
Procedure: Longitudinal study in Canada @ 5,18,30,48 and 60 months and finally at 6yr

• Peer and teacher ratings were given on social and physical aggressive behaviours.
• Social aggression factors included the extent to which a child tried to make others dislike him or her, made friends with another

for revenge, spread rumours.
• Physical aggression was the extent to which a child got into fights, physically attacked others, hit, bit or kicked others.
Measures of aggression:
• Observations, peer-report, parent/caregiver, teacher ratings
• Teachers: Responses were given on a 3 point scale
• Peers: shown photos and asked to circle three which best fit the descriptions
Results: 82% received at least one nomination as among the top 3 most socially aggressive in the class

62% received at least one nomination for the top three most physically aggressive in the class
Teachers ratings: Boys were more physically aggressive than girls. Girls more socially aggressive
Peer ratings: boys more physically and socially aggressive than girls
Overall environmental factors were more correlated with social aggression and biological factors were more correlated with
physical aggression
Conclusions: Environmental conditions interact with genetic factors suggesting aggression and violent interactions are an interplay
between the two.
Young children are capable of using complex manipulative strategies in addition to physical means to harm their peers
Strengths: The first of its kind to examine the effects of nature/nurture, Reliability is increased by using both teachers and peer ratings
which showed a lot of similarities. Using MZ and DZ is a good way of studying nature and nurture and matching for gender is a good
control.

Weakness: Small sample size, Cannot generalize the results beyond the assessed age as aggression may not develop until 8yrs. The

behaviours observed could be a result of imitating. It is not possible to separate twins from a shared environment.

3. PSYCHODYNAMIC THEORY OF AGGRESSION

Key assumptions
1. The importance of the unconscious mind and motivation:

 Conscious thoughts are those we are aware of
 Preconscious thoughts are those we can become aware of
 Unconscious wishes and desires are those we cannot access directly but they

influence our behaviour. 9/10ths of our mind is unconscious, therefore we cannot
access unconscious wishes and desires but they motivate our behaviour and use up our energy by repressing unconscious
wishes and desires.

2. The importance of early experiences:
Freud believed the first 5 yrs of life in our early childhood experiences defines our personality which is made up of the id, ego and
superego. A lot of anxiety is due to conflict with our parents during this time which he calls psychosexual development. If we can pass

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through these stages successfully then we can grow to be healthy adults, if unresolved conflicts occur at any stage it can lead to
fixation and defence mechanisms

3. We have 2 instinctive urges: life (eros) and death (thanatos) instinct, these basic drives shape our behaviour. Urges and wishes in
the unconcious leads to arousal of the Libido (sexual energy).

Psychosexual stages:
Oral (0-2) - pleasure focused on the mouth, e.g. sucking
If fixated here the person will be passive and dependent and may smoke.
Anal (2-3) - pleasure focused on the anus, e.g. potty training
If fixated here the person will be anally retentive and be tidy and mean. You can also be anally expulsive.
Phallic(3-6) - masturbation starts. Oedipus complex for boys- desires his mother, jealous of father, fears castration, identifies
with father. Electra complex - desires father and identifies with mother. Penis envy.
Latent (6-puberty) - superego develops
Genital (puberty+) - if no problems then desire the opposite sex.

Fixation refers to not resolving issues in one of the stages and therefore being held back. Resolving the issue later is important to
maintain a healthy balance.

Tripartite Model of personality:
 Id - it represents our wishes and desires “pleasure principle”, I want!
 Ego - makes decisions based on the demands of the id and restrictions of the superego, “reality principle”.

 Superego - “Morality principle” we learn these principles from our parents and society.

The ego has to find a blalance between the two so does this by repressing unwanted or unacceptable thoughts into the unconcsious.
Sometimes they leak out in dreams, defence mechansims or through talking.

Defence mechanisms:
Designed to help the Ego keep the peace between the demands of the id and the superego.

Repression - Repression involves keeping unwanted thoughts into the unconscious and not
allowing them to surface into the conscious.
Denial – when something traumatic happens which is hard to deal with the person denies that it
happened at all. This is not a conscious process, the person does not realise they are in denial.
Denial can protect a person from inappropriate sexual feelings.(Homosexuality)
Regression - going back to an earlier stage - sucking thumb.
Displacement - taking out anger on something else
Sublimation - healthy displacement i.e. gardening.

Psychoanalysis and aggression
Methods include dream analysis, symbol analysis, free association and slips of the tongue. (Psychoanalysis). His patients were middle-
aged women from Vienna suffering from neurosis, and people with phobias. E.g. Little Hans.
His aim was to uncover unconcsious thoughts, to free the id’s impulses from excessive control thus releasing emotions and anxiety.
(Catharsis). Catharsis is an emotional way to vent aggression, watching agression on TV or a boxing match, playing Xbox.

Aggression is linked to the death instinct. The child unconscioulsy feels aggression towards the parents as they will prevent things that
will give them pleasure (demands of the Id) the superego prevents the anger being directed to them because the child knows it is loved
so the aggression is turned into guilt.
Fromm (73) suggests two types of aggression; one where the individual is naturally threatened by someone or something in the
environment (attack from predator) and destructive aggression where someone wants to achieve their own goals.(crime)

Reliability The unconscious mind cannot be tested so there is no scientific measurement or evidence . Qualitative data is
Validity hard to replicate because in another situation the person may say something different and the researcher may
interpret it differently. Eg Little Hans could not be repeated as he was growing all the time and access to the
parents would be needed.
Qualitative data is about real life and real people, so the data is not artificial. However, Little Hans’ dreams,
emotions comments etc were reported through his father, so validity of the data is affected by parent’s
interpretation. Psychoanalysis has been shown to be successful; we accept that childhood experiences have an
effect on our personality.

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Subjectivity/objecti Science needs to be objective and free from bias. With qualitative data there is always an element of bias
vity because the researcher will affect the data by the way it is interpreted
Generalisability Qualitative data involves information from unique individuals which means the findings are unique. Findings can
be generalised if the cases were similar of similar people.
Credibility Case studies are credible in the subjective sense because of the depth and detail of the data. In the objective
sense they are not credible because of the subjective way data is collected. Freud’s data lacks credibility
because there is no evidence of what is really in the unconcsious.

KEY ISSUE

What are the implications for society if aggression is found to be caused by nature not nurture?

Nature: (Etic) argument which states that our behaviour and characteristics are due to genetic factors - nativists
Nurture: (Emic) argument which states that our behaviour and characteristics are the product of the environment in which we live.-
empiricists

The debate is not about whether characteristics and behaviour are one or the other but rather to what extent they are influenced by
both as it is now accepted that most characteristics are influenced by both nature and nurture.- Interactionists.
In practice, genetic and environmental influences operate together. A child’s ability at sport will be determined by his/her genotype,
which will strongly influence body shape, strength, speed and coordination. However, environmental factors, such as disease,
malnutrition (an unbalanced diet, shortage of food or excess of food), parental encouragement and training opportunities can also have
a decisive effect. For a child to excel at sport, the majority, if not all, of these factors should be positive. An ideal environment cannot
compensate for an unsuitable genotype. Equally, an ideal athlete’s genotype cannot compensate for the effects of an unhealthy
environment.

Another example is the likely interaction between a child’s temperament and parental behaviour. Parents can get impatient with, or
even reject, children whose temperaments make them difficult to cope with. This sort of parental response can itself influence the
child’s personality development.(Freud)

NATURE NURTURE
Environmental cause
Biological cause Individual choice to behave in that way and can avoid the
Determined at birth, individual has limited choice to change triggers or choose to behave differently
behaviour. Aggressions is learned and can therefore be unlearned
inherited something that causes aggressive behaviour? Brain damage could be caused by environmental factors
Evolutionary psychology: suggests it is in our template to survive The development of id,ego, superego could be affected by
and protect offspring and pass genes on. Impulsivity is a survival events in the first 5 years while personality was developing
mechanism to allow the individual to think and act quickly and Freewill Vs determinism
controlled by the prefrontal cortex
Brain structure: Stimulation of hypothalamus and limbic system
suggest aggression comes from brain functioning and structure.
(small amygdala)
Charles Whitman, Phinneus Gage, Raine
Biochemistry: tesosterone and low cortisol is linked to
aggression. High levels of tesosteroneis linked with traits such as
dominance and competitiveness which is linked to sports.
Imprisonment is a waste of time/unfair if out of a person’s
control? Moral issue
Anxiety and depression get treated in society whereas aggression
and anger results in punishment. (all linked to emotions). Is
aggression a form of illness or a symptom of a disorder?

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INDIVIDUAL DIFFERENCES
Drugs affect people differently. This may be due to differences in brain chemistry or influences in the
environment.

Issues and debates

Ethics

Practical issues of scanning

Reductionism Explaining aggression in terms of brain functioning is reductionist. It reduces the production of
aggressive behaviour and all that it entails down to the working of specific neural circuits and ignores
Comparison with another other possible causes such as social learning. Cultures vary in the amount of aggression displayed
explanation which could be caused by social learning as opposed to differenecs in brain structure.

Psychology as a science Using animals allows for scientific rigour. More control is possible as the animal can be genetically
Culture and gender bred for a specific study and the environment can be carefully monitored. This removes the chance
of extraneous variables affecting the outcome of the study and enabling objective data to be
gathered leading to clear cause and effect conclusions. This level of control would not be possible
with human participants

Nature-nurture Biological psychologists look at the role of genes and brain function in aggression while Freud
considered the role of personality factors which develops through maturation and upbrining. Brain
Development of damage could however be caused by the environment and genes can be expressed by the
psychological understanding environment (epigentics), the role of nurture cannot be ignored.

Social control Pre-frontal lobotomy is an operation that severs the connection between the llimbic system and the
Using psychology in society prefrontal cortex. This was effective in reducing aggression but it also reduced all other emotional
reactions too andis no longer regarded as ethical.

Socially sensitive research Gathering accurate and reliable information about people’s life experiences such as adoption is
Freewill Vs Determinism difficult and socially sensitive, especially in fields of research into aggression. People may be
reluctant to take part in a study that looks into their biological and adoptive families, it may be
uncomfortable of difficult to access the information and can be criticsed for labelling or it sends out
negative messages.

Behaviour is predetermined by our biological makeup/evolution and the individual has no free will or
choice how they behave and removes blame. For example people with smaller amygdala and low
activity in the preforntal cortex are destined to be aggressive. These ideas can be used as a defence
for violence such was the case in Raine’s research. This provides an excuse for some people to
engage in violence as they could say that it is beyond their control and therefore they are not
responsible for the violent outbursts. By ignoring the effects of nurture it limits a willingness to
engage in treatments such as anger management programmes and they might believe them to be
futile.

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