LEARNING OUTCOMES
• Define 'hormone'.
• Identify two different hormones.
• Identify the connection between the endocrine system and hormones.
• Examine the effect of a hormone using one or more examples.
• Identify and define 'pheromone'.
• Discuss arguments for and against the existence of pheromones.
• Examine an effect of oxytocin on human behaviour.
• Examine an effect of testosterone on human behaviour.
HORMONES AND BEHAVIOUR
• Cells in our body communicate with each
other
through
networks
of
neurons,
neurotransmitters
or
through hormones. Think of hormones as
the Wi-Fi of the body: wireless tools of
communication
that
facilitate
communicating over long distances and
long periods of time.
• While neurotransmitters and hormones
are both chemicals, the difference is that
neurotransmitters are generally produced
by neurons at synapses when triggered by
an electrical impulse. Hormones, on the
other hand, are produced by endocrine
glands and released directly into
the bloodstream.
• The pituitary gland and pineal
gland are located in the brain,
but the rest of the glands are
located
throughout
the
body. Hormones influence a
wide range of psychological
processes,
and
different
hormones are known to have
an impact on metabolism, the
sleep/wake
cycle,
reproductive activities and
mood, to name a few (US
National Library of Medicine,
2014).
HORMONES
• Although neurotransmitters are generally active between neurons,
and hormones are generally active in the bloodstream, the
distinction is actually a bit more confusing. This is because some
chemical messengers can act as both hormones and
neurotransmitters, such as adrenaline (also known as epinephrine)
and noradrenaline (or norepinephrine). Both examples are secreted
as hormones in the body by the adrenal medulla (at the centre of
each adrenal gland, just above the kidneys) and by neurons in the
nervous system.
DISTINCTION BETWEEN HORMONES AND NEUROTRANSMITTERS
• Neurotransmitters are produced in the
brain and elsewhere in the body; they
activate target cells at a short
distance
(usually
less
than
a
micrometre, between neurons); they
have a relatively immediate effect on
behaviour.
• Hormones are produced by endocrine
glands
and
released
into
the bloodstream; they activate target
cells located at a long distance (usually
another part of the body); they have
a slower effect on behaviour
Important
• Although neurotransmitters cannot be considered hormones, some hormones
do act as neurotransmitters, such as adrenaline. It is important to understand
that hormones interact with cells throughout your body, including your brain.
• There are 50 different hormones in the human body and all are collectively
responsible for a variety of communication purposes and functions
QUESTIONS
1. Identify the hormone that is associated with stress in the body.
• Cortisol, Orexin, Gherlin, Testosterone.
• 2. What is the system in the human body responsible for producing
hormones?...............
• 3. This hormone is associated with aggression. What is it
called?........................
Table 1. Key hormones and their functions.
Hormone
Testosterone
Adrenaline and noradrenaline
•
Main function
Sex hormone present in both males and females

Syllabus connections
See Testosterone and behaviour for details.
•
Facilitates sexual maturation

Aggression
•
Aides in creation of muscle mass

Down-regulation of trust
•
Affects voice tone development during puberty
Helps to regulate heartbeat

Emotion (cognitive psychology)
Released during the 'flight-or-fight' response. A response named for
an organism's biological response to threat, wherein physiological
responses prepare the organism to fight a threat or escape from it.

Fight-or-flight response

Stress

Found in the stomach
•
Obesity (Health Psychology)

Stimulates appetite

Created in the hypothalamus

Obesity (Health Psychology).

Associated with wakefulness and energy levels

Serves to increase appetite
Facilitates the expression of milk from the milk ducts in females and
serves to ready the body for childbirth via stimulation of the uterus

See Oxytocin and behaviour for details

Trust
Research has linked oxytocin to the behaviours of interpersonal
trust, affection, pair bonding, love and attraction.

Affection



Ghrelin
Orexin
Oxytocin


Cortisol

Involved in blood pressure regulation

Pair bonding
Stress (Health Psychology)

Immune system functioning

Immune system functioning

Environmental influence on physiology
OXYTOCIN AND BEHAVIOUR
https://youtu.be/rFAdlU2ETjU
• Oxytocin may be the most famous hormone on Earth. Oxytocin has
been labelled the 'love hormone', 'cuddle hormone', and 'trust
hormone'. It has been linked to animal therapy and sexual health, and
is used to explain the bond between mother and child.
• Oxytocin is produced in the hypothalamus and secreted by the pituitary
gland. One of oxytocin's main functions is to prepare a pregnant
woman for childbirth and breastfeeding, as it is increased at times
of labour and lactation. It is also important in human social bonding
and has been shown to increase trust, affection and cooperation in
both animals and humans.
• Trust has been described as an
'essential social tool' that allows
people
to
form
meaningful
relationships, but the bonds of trust
are easily broken (Delgado, 2008). The
consequences of breaches in trust can
be disastrous for human relationships,
and they may also play into larger
social phobias when people who are
betrayed
begin
avoiding
social
interactions (Delgado, 2008). Recent
research has investigated the biological
correlates
of
trust,
seeking
explanations on a neuronal level.
. Studies have established a positive correlation between
oxytocin and trust. As oxytocin levels go up, so too does trust.
BAUMGARTNER ET AL.(2008)
• In a study published in Neuron, Baumgartner et al. (2008) manipulated oxytocin
exposure in an experimental setting. Their aim was to investigate the role that
oxytocin plays in trust in spite of that trust being breached. This was examined
by requiring participants to take part in economic simulations.
The procedure was as follows:
• Brain activity was measured using fMRI.
• The 49 participants were given either oxytocin or a placebo, administered via a
nasal spray.
• Participants played multiple rounds of an economic trust game, in which they
acted as investors with another trustee.
• Participants also played multiple rounds of an economic risk game against a
computer.
• During each phase, participants were given feedback indicating that about half
of their investment decisions resulted in bad investments: either their trust had
been breached (in the trust game) or their gamble had not paid off (in the risk
game).
BAUMGARTNER ET AL.(2008)
• The researchers were particularly interested in the differences between
investment decisions before and after knowledge of broken trust. To meet this
aim, halfway through the investment game, participants were informed
that their trust was broken 50% of the time on prior rounds. The results were as
follows:



Participants in the placebo group were more likely to lower their rate
of trust after receiving feedback that their trust had been broken.
Participants in the oxytocin group continued to invest at comparable
rates. It did not seem to matter to them that their trust has been
broken by their partner.
The Baumgartner et al. (2008) study is significant because it establishes a clear
correlation between the hormone oxytocin and the human behaviour of trust.
BAUMGARTNER ET AL.(2008) CONCLUSION


The researchers concluded from the fMRI scan that different areas of the
brain were active in each of the two groups. Participants in the oxytocin
group showed decreased responses in the caudate nucleus and
the amygdala. The amygdala is a brain structure involved in emotion, and
the caudate nucleus is linked to reward behaviours and trust (Delgado,
2008).
The results only showed when participants played the trust game – they
were not apparent in the risk game. This suggests that oxytocin’s effects
on trust are exclusive to interactions with real people. Oxytocin appears to
decrease fear reactions that may arise as a consequence of human
betrayal. In other words, it appears to encourage trust. Either that, or it
makes it more difficult to learn from mistakes made while trusting people.
Table 1. Strengths, limitations and implications of the study by Baumgartner et al. (2008).
Strengths
Limitations
Implications
At the time of publication, it was the first study to establish a Although it can be deduced that oxytocin mediates
Trust is a crucial component of social existence. It is the glue
statistically significant correlation between oxytocin and
neurological response in the caudate nucleus and amygdala, that holds society together, therefore any findings that
behavioural adaptation after feedback, in regard to trust and which in turn influences the 'trust' levels of participants, it is elucidate biological elements of trust are highly significant.
risk taking.
not clear how this happens.
Insights gained from this study could help explain the dynamics
The findings of the study are triangulated by other
'Trust' was measured as a function of willingness to invest in of trust in human relationships as well as inform how humans
research such as Kosfeld et al. (2005), who also found that
spite of knowledge of broken trust. In actuality, this may not be re-establish trust after a violation by a significant other.
increasing oxytocin in participants increased their willingness 'trust' but 'lack of fear' or disillusion of 'threat'.
The findings of the research could provide insight into mental
to engage in social risk.
Presumably, the participants took the game seriously and were disorders that involve a lack of trust, such as autism and social
49 participants is a relatively large sample size given fMRI was interested in achieving maximally beneficial outcomes.
phobias. The researchers wrote: 'We hope that our results will
used. The technology is quite expensive and therefore
However, it was still a game inside of a laboratory and
lead to further fertile research on such health disorders and the
generally studies that use it have smaller sample sizes.
therefore ecological validity is minimised.
potential role of possible dysfunctions in neuroendocrine
mechanisms such as the oxytocinergic system.'
Use of the fMRI machine was able to establish a correlation As mentioned above, oxytocin could inhibit learning as
between trusting behaviour and increased oxytocin activity in opposed to increase trust.
the brain.
Ecological validity is limited, as administering oxytocin like this
It had two sets of data: fMRI results as well as the behavioural in an experiment may not reflect natural physiological
investment rate data. This made the findings of the research processes.
more robust.
In spite of randomisation, it is possible that some of the
Participants were blind to whether or not they received
participants in the experimental condition were generally more
oxytocin.
trustworthy than others whether they received oxytocin or not.
Findings were localised and consistent with previous
The function of oxytocin is very complex and it is too simplistic
research. The researchers wrote: 'The differences in brain
to say that it alone creates trust.
activation between placebo and OT [oxytocin] subjects were
only observed in subcortical structures as the amygdala, the
midbrain, and the striatum.'
QUESTIONS
1. Identify the name of the researcher who investigated the role of
oxytocin in trust.
2. In Baumgartner et al.'s (2008) study, fMRI scans of the participants
in the oxytocin group showed decreased brain activity relative to the
control group in which brain regions?
A. Amygdala and caudate nucleus.
B.Hypothalamus and caudate nucleus.
C. Cerebral cortex and amygdala.
D. Cerebellum and frontal lobe.
3. An effect on trust was only demonstrated when participants played
this style of economic exchange game. What is it called?
Exam tip
• Critical thinking is consistently the hardest markband for IB students to
achieve high scores on. A big reason for this may be a misunderstanding of
what constitutes critical thinking in an IB context.
• One way students can demonstrate critical thinking is by linking the findings
of one piece of research to conceptually-related findings of another piece of
research that is not traditionally used within the given context. This is a
type of conceptual triangulation and demonstrates an advanced
comprehension of the topic at hand.
• For example, in the Baumgartner et al. (2008) study, the researchers found
that increasing oxytocin resulted in a decrease in activity within the
amygdala and the striatum. This in turn led to increased trust, or, put
another way, decreased perception of possible threat.
• The amygdala was the key brain area of focus in Feinstein's case study of
SM. If you recall from the section on localisation of brain function, SM did
not have a biological threat detection response as she did not have an
amygdala.
Testosterone and behaviour
• Men commit 80% of the violent crime in
America for example, and are
imprisoned at much greater rates than
women. Research suggests that this is
due to men having (on average) 78 times more testosterone in their body
than
women
(Torjesen
and
Sandnes, 2004).
• Testosterone is a hormone that is
produced by the endocrine system in
both men and women. In men, the
majority of testosterone is produced by
the testes with the adrenal gland
producing relatively small amounts. In
women, testosterone is produced by
both the ovaries and the adrenal gland.
Males are much more likely than females to be
convicted of a violent crime. Many researchers
believe this is partly due to a male's higher levels
of testosterone.
TESTOSTERONE AND BEHAVIOUR
• Testosterone
serves
many
functions in our body, such as
helping to:
• maintain reproductive tissues
• stimulate sperm production
• stimulate and maintain sexual
function
• increase muscle mass and
strength
• maintain bone strength.
Testosterone is linked to muscle growth in males and
females.
Testosterone and human behaviour
• Dabbs et al. (1987) investigated the role of testosterone in aggression by
taking saliva samples of 89 male prison inmates. They found that 10 out of
11 men with the highest concentration of testosterone were convicted of
violent crimes. In contrast, 9 out of the 11 males with the lowest
testosterone levels had been convicted of non-violent crimes.
• Dabbs et al. (1987) found that the inmates rated the 'toughest' and 'most
aggressive' by their peers had the highest levels of testosterone within that
population. Additionally, the inmates who received parole earliest for good
behaviour while in prison were among those with the lowest testosterone
levels. testosterone is a hormone that plays a role in human aggression.
Bos et al. (2010) – testosterone and trust
• In their study, Bos et al. (2010) created double-blind repeated measures as
a laboratory experiment with the aim of investigating the role increased
testosterone has on interpersonal trust. Their procedure was as follows:
• Participants consisted of 24 young women with a mean age of 20.2 years
recruited to the study through opportunity sampling.
• Saliva samples were taken from all participants to measure baseline
testosterone levels.
• Each participant came to the lab on two separate occasions. Each time, she
was administered with either 0.5 mg of testosterone via oral dosage or an
oral placebo. The participant and researcher were both blind to whether
the pill given was testosterone or a placebo.
Bos et al. (2010) – testosterone and trust contd.
• At each session, the participants engaged in a 'trustworthiness task'. This
consisted of viewing greyscale images of faces on a computer screen and
requiring the participants to assign a trustworthiness rating to each face.
The participants used a cursor to slide an indicator towards one of three
terms: untrustworthy, neutral or very trustworthy. The cursor could reside
in between terms and the software then coded the rating as a number
from –100 (very untrustworthy) to 100 (very trustworthy).
• The researchers chose this visual assessment task as their aim was to
investigate social trust. They believed that we draw conclusions on an
individual's trustworthiness based on a variety of social factors including
appearance.
• The results were then analysed using statistical analysis.
Bos et al. (2010) – testosterone and trust contd.
• In discussing their incredibly interesting results, the authors did so
through an evolutionary lens. They wrote:
• Testosterone increased social vigilance in trusting humans, presumably
to better prepare them for the hard-edged competition over status and
valued resources. These findings provide insight into the hormonal
regulation of human sociality by showing that the hormone
testosterone downregulates interpersonal trust in an adaptive manner.
• In short, Bos et al. (2010) concluded that testosterone plays a causal
role in reducing interpersonal trust among unfamiliar individuals.
Testosterone and Social Status
• It has long been theorized that testosterone contributes to aggressive behaviour.
Researchers from Trinity College in Dublin (Dunne et al. 2016) sought to clarify this
theory and add nuance to our understanding of the role of testosterone in social
interaction.
• The researchers hypothesized a more comprehensive understanding of the role of
testosterone in human behaviour. Specifically, the researchers hypothesized that
testosterone increases behaviour that is likely to lead to elevating one’s social statusIn
order to test this hypothesis, the researchers (Dunne et al. 2016) conducted a doubleblind, between subjects, randomized laboratory experiment with 40 participants.
• The procedure included participants being randomly assigned to either the
testosterone condition or the placebo condition in which individuals were either
injected with testosterone or a placebo.
• Participants then engaged in a version of the ultimatum game (as described in 2.B.2)
but with the added modification that after or rejecting the offer put forth by the
“proposer,” the “receiver” could punish or reward the “proposer” for the offer they
put forth.
Testosterone and Social Status
• The results indicated that individuals who received the testosterone injection
were more likely to punish the proposer when an “unfair’ offer was received.
Additionally, participants who received testosterone were also more likely to
reward the “proposer” when large offers were received and the reward
amounts returned to the “proposer” were larger.
• The researchers also measured the baseline levels of all participants and when
they analyzed the testosterone levels of those participants who received the
placebo, they found that among these placebo participants, those who had
higher levels of testosterone also doled out higher levels of reward and
punishment.
• This led the researchers to conclude that testosterone does not only affect
“violent” or “aggressive” behaviour, but that it also mediated the willingness
to reward individuals for “good” or “moral” behaviour (Dunne et al. 2016).
• Another group of chemical messengers are referred to
as pheromones. Pheromones are present in many animal species and
facilitate interspecies communication (as opposed to hormones and
neurotransmitters which facilitate cellular communication within an
organism).
Important
• As is the case with all research on biochemical correlations of
behaviour, it is important to be wary of over-attributing total causality
to behaviours associated with hormones and pheromones. However,
having sound knowledge of these biochemicals can help to facilitate a
more complex and holistic understanding of human behaviour.
PHEROMONES AND BEHAVIOUR
Pheromones were first discovered in butterflies
and moths. Both species use them to communicate
with potential mates over incredibly long
distances.
• Pheromones were identified via animal
research in 1959 by Karlson and Luscher.
They can be referred to as ‘ectohormones’ as they are chemical
messengers that are emitted into the
environment from the body where they
can then activate specific physiological
or behavioural responses in other
individuals of the same species.
• The earliest research into pheromones
focused on animals and sexual
reproduction, which was indeed the case
with
Karlson
and
Luscher's
(1959) research into the butterfly
pheromone of bombykol Karlson and
Luscher (1959) found that as little as one
molecule of bombykol released by a
female butterfly could attract a male
butterfly from over 2 km away.
PHEROMONES AND BEHAVIOUR CONTD.
• In a subsequent study, Hilda Bruce, working at the National Institute for
Medical Research in London, found that if a recently impregnated
female mouse was placed in a cage with an unknown male, the chance
of miscarriage increased dramatically to 41% (Bruce, 1959).
• This finding implies that somehow the female's body is reacting to the
presence of the male mouse and that possibly pheromones from the
male could be communicating with the female, informing her that she
should reject the offspring of a separate male who is no longer in the
parental picture.
Do humans have pheromones and can we sense them?
• According to Grammer et al. (2005), pheromones do indeed
exist in humans and are produced in the apocrine glands found
in the armpits of both males and females. Pheromones are also
believed to be produced by females in the vagina and are
sometimes referred to as copulins. Research has established
that copulin scent varies with a woman's menstrual cycle.
• However, there are some researchers, such as Tristram Wyatt
of Oxford University, who are not yet convinced of the
existence of human pheromones. Writing in the Proceedings of
the Royal Society: Biology he unequivocally states that: 'There
is no robust bioassay-led evidence for the widely published
claims that four steroid molecules are human pheromones',
although he allows for the possibility that 'We can anticipate
finding human pheromones on evolutionary grounds because
we are mammals.'
Do humans have pheromones and can we sense
them?
Bioassay is a type of experiment that determines the effect of a
substance on human cells or tissue. There are five different types of
bioassay procedures, though all involve the administration of a
substance and a consistently observed response from living
biological cells or tissue. The investigation also focuses on the
amount of a substance necessary to induce the biological
response.
He goes on to say that it is quite possible we have lost the ability to
both produce and detect pheromones due to a lack of selection
pressure.
VOMERONASAL ORGAN OR VNO
• Researchers on both sides of the issue give a lot of attention to the
vomeronasal organ, or VNO. The VNO is sometimes referred to as
'Jacobson's organ' or 'second nose' and is present in many animal species
such as snakes, elephants, turtles, cats, dogs and goats. The VNO is located
above the hard palate in the mouth and has nerves that extend directly
into the accessory olfactory bulb (which helps animals to smell).
• The controversy regarding the VNO is not about whether or not we have
one, for post-mortem dissections have established that humans do
possess a VNO, but rather whether or not it is functional Grammer et al.
(2005) side with the research asserting that humans do possess a
functional VNO, while Wyatt contends we do not. For Wyatt, the presence
of a functioning VNO is subject to debate, as there are many instances of
mammals using their main olfactory system to detect pheromones.
Research-based evidence for and against pheromones' effect on behaviour
In Grammer et al.'s (2005) meta-analysis, they cite a few key studies in
support of their assertion that human pheromones do indeed exist and play a
role in behaviour. The most interesting of these is the 'stinky t-shirt'
experiment conducted by Wedekind and Füri (1997).
• Wedekind and Füri required 120 male and female participants to assess the
odours of six t-shirts worn by two women and four men for two days
straight.
Their
research
hypothesis
predicted
there
would
be a negative correlation between positive rankings of odour by the
participants and similarity of major histocompatibility complex (MHC).
• Given that the MHC genes are responsible for immunological functioning,
the researchers believed that the t-shirts with the most appealing odours
would belong to participants with the greatest variation of MHC relative to
the individual. This is because genetic differences in MHC genes are
associated with advantageous immune functioning.
Study
Baumgartner et al. (2008) Aim: To investigate the role of oxytocin in creating trust.
Description
Evaluation
Strengths:
Method: Laboratory experiment. 49 participants were placed in an fMRI scanner. 
They received either oxytocin or a placebo (a harmless substance that would
have no biological effect) via a nasal spray. Participants were then told to act as
investors in several rounds of a trust game involving financial risk, with different
trustees. They were also told that they were to engage in a risk game, which is 
the same as a trust game in terms of financial risk but it is played against a
computer instead of a human partner.

It was insightful in that the study utilised fMRI
technology to precisely locate localised effects of the
oxytocin hormone and found that it decreased
amygdala and caudate nucleus response.
Although a trust game played while in an fMRI machine
and is not the same as trust interactions in society, the
design was strong.
For an fMRI study, 49 participants is a high number.
The feedback given to the participants after they had engaged in both games
Control group was used.
indicated that about 50% of their decisions resulted in poor investment because 
their trust was broken.
Limitations:
Result: The feedback had different results. Participants who had received a

Trust game played in context of fMRI machine could
placebo before they started playing were more likely to decrease their rate of
result in demand characteristics and minimise ecological
trust after they had been briefed that their trust had been broken. Participants
validity.
who had received oxytocin in the nasal spray continued to invest at similar rates.
Methodological considerations:
Apparently it did not matter to them that their partner had broken their trust.
The researchers could also see that different brain areas were active in the two 
Studies using fMRI machines run the risk of yielding a
groups. Participants in the oxytocin group showed decreases in responses in the
Type II error or false positive results. Brain scans are still
open to interpretation and they should be analysed by
amygdala and caudate nucleus. The amygdala is a structure in the brain involved
professionals to minimise this risk.
in emotional processing and fear learning. It has many oxytocin receptors. The
caudate nucleus is associated with learning and memory and has a role in
Ethical considerations:
reward-related responses and learning to trust. The results observed were only

There were no real ethical considerations with this
apparent when participants played the trust game, but not the risk game,
study.
suggesting that oxytocin’s effects on trust are exclusive to interactions with real
people.

All researchers conducting studies within the field of
Conclusion: Oxytocin appears to decrease fear reactions that may arise as a
consequence of human betrayal. Therefore, it decreases our ability to learn from
mistakes made in trusting people.
psychological research are expected to consider ethical
guidelines as discussed in 1.A.5.
Bos et al. (2010) Aim: To investigate the role increased
testosterone has on interpersonal trust.
Strengths:

These findings provide insight into the hormonal regulation of
human sociality.
Method: A double-blind repeated-measures
(counter-balanced) designed laboratory

It provided the incredibly interesting insight into testosterone
experiment was conducted. Participants
selectively downregulating an interpersonal behaviour.
consisted of 24 young women with a mean age of
20.2 years recruited through opportunity
Limitations:
sampling. Saliva samples were taken to measure

The 'trustworthiness task' used in the laboratory experiment had
baseline testosterone levels. Each participant
low ecological validity.
came to the lab on two separate occasions. Each
time, she was administered either 0.5 mg of
testosterone via oral dosage or an oral placebo.  The rating methodology was somewhat artificial in using a scale
rating system and the participants could have differing concepts of
At each session, the participants engaged in a
what 'trustworthy' is.
'trustworthiness task'.
Methodological considerations:
Results: When the participants were compared as
a whole, there was no statistically significant

difference in trustworthiness ratings between the
placebo and testosterone conditions.
However, when the researchers separated the
participants, placebo trustworthiness ratings
were either 'high trusting' (n=12) or 'low trusting' 
(n=12) groups, while the testosterone did not
affect participants in the 'low trusting' group.

Instead, it lowered the trust behaviour in the
baseline 'high trusting' group.
Conclusion: Testosterone downregulates
interpersonal trust in an adaptive manner in
highly trusting people.
Counter-balanced repeated measures design allowed for
comparison of trust change within the same participant and
randomised the order of placebo /testosterone condition in order
to minimise confounding variables.
The researchers controlled for possible variance in natural
testosterone levels due to menstrual cycle.
The double blind procedure reduced participant and researcher
bias.
Ethical considerations:

Any invasive study, where participants ingest a substance raises
issues of protection of harm.
To investigate the relationship between Strengths:
Wedekind and Aim:
similarity of major histocompatibility
complex (MHC) and attractiveness of scent.  Provides support for the role of pheromones
Furi (1997)
Method: 120 male and female
participants assessed the odours of six tshirts worn by two women and four men for
2 days straight.
in affecting behaviour.
Limitations:
Is a highly reductionist view of the complex
human behaviour of mate choice.
Methodological considerations:

Results: Participants preferred the scent of t
shirts worn by people with the most
different MHCs, and this finding was nongender specific.
differences in MHC and from differences in
pheromones.
Conclusion: Individual odour plays a role in
mate choice and is non-gender specific.
Individual odours may differ as a result of
both
Although many controls were put in place,
the researchers could not be sure that the
confederates actually wore the t-shirts and
refrained from the smell-inducing activities
as they were asked to for the 2-day period.
Ethical Considerations:

There are no major ethical considerations
for this study.
To investigate the role of pheromones on
Thorne et al. Aim:
female ratings of male attractiveness.
(2002)
Strengths:
Provides external reliability to other
pheromone studies.
Method: 32 female undergraduate students were
selected for the study via opportunity sampling. Limitations:
Half of the participants were contraceptive pill
users. The participants came to the laboratory on  Wyatt suggests studies like these may
two separate occasions based on menstrual cycle
be prone to false positives.
phase. During both visits to the lab, participants
Methodological considerations:
were asked to rate the attractiveness of male
faces. A counter-balanced, repeated measures
design was used where the experimental

The studies have not been peercondition involved exposing the females to male
reviewed.
axillary secretions believed by the researchers to
be pheromones.
Ethical considerations:


Results: There was a significant positive
correlation between exposure to male axillary
secretions and ratings of attractiveness. There was
no effect of menstrual cycle or contraceptive use
on ratings of attractiveness.
Conclusion: Exposure to natural male axillary
pheromones can significantly enhance female
perceptions of various aspects of male
attractiveness.
There are no major ethical
considerations for this study.
TASK
1. Wyatt of Oxford University suggests this area of focus for future research on human
pheromones: ______; Your answer here;
A. Breastfeeding B. Sexual attraction
C. MHC identification via scent D. Medical diagnoses
such as cancer
2. In regard to the results attained by Wedekind and Füri (1997), Wyatt would argue that: ______;
Your answer here;
A. The study wasn't properly controlled
B. Genes don't matter
C. Information is not communication
D. The study is too old to be valid
3. This researcher from Oxford University does not believe that there is any evidence for human
pheromones: ______; Your answer here;
4. Bos et al. (2010) was incredibly interesting because the researchers found a very strong
correlation between testosterone and: ______; Your answer here;
A. Lowering trust among naturally high-trusting individuals
B. Lowering trust among naturally
low-trusting individuals
C. Raising trust among naturally high-trusting individuals
D.
Raising trust among naturally low-trusting individuals
TASK
5. Dabbs, Frady et al. (1987) investigated the role of this hormone in aggression:
6. The fact that men commit 80% of the violent crimes in America could best be said to
be evidence for the following:
A.Ghrelin's effect on behavior
B.Social identity theory
C. Biological factors
influence on behaviour
D. Gender roles
7. Baumgartner et al. (2008) found that oxytocin appears to decrease fear reactions
that may arise as a consequence of human betrayal. In other words, oxytocin appears
to encourage trust. All of the following are limitations of the study except:
A. Participants were not blind to the fact they received oxytocin B. In actuality, this
may not be 'trust' but 'lack of fear' or disillusion of 'threat‘
C. Oxytocin could
inhibit learning as opposed to increase trust
D. Administering
oxytocin like this in an experiment may not reflect natural physiological processes
8. What evolutionary explanation for oxytocin's abundance in humans
did Baumgartner et al.'s (2008) study find?
A. Oxytocin increases levels of trust B. Oxytocin increases sexual desire C. Oxytocin
increases long-term memory capabilities
D. Oxytocin inoculates the body against
stressors
TASK
9. The following are all glands of the endocrine system except:
A. Kidneys B. Pancreas C. Thyroid D. Testicles
10. Increased amounts of which hormone are associated with stress?
A. Oxytocin B. Serotonin C. Ghrelin D. Cortisol
11. All of the following are pairs identifying distinctions between neurotransmitters and
hormones except:
A. Short distance vs. long distance B. Slow-acting vs. fast-acting
C. Inter-cell
communication vs. intra-cell communication D. Glands vs. brain
12. True or false?
The Wedekind and Füri (1997) study found that males and females rated the
'attractiveness' level of sweaty T-shirt smells based on the most beneficial (from an
evolutionary perspective) major histocompatibility complex (MHC) as a result of
pheromone communication.
TASK
13. Which of the following is NOT true of pheromones?
A. Bioassay studies in humans have established pheromone activity.
cells.
B. Pheromones are detected by olfactory nerve
C. Pheromones facilitate communication among organisms of the same species. D. Pheromones can travel to distances
over one metre.
14. Which of the following is NOT a limitation of the Bos, Terburg and Van Honk (2010) study?
A. The population sampled was not a population to which the results could apply, therefore the study had reduced
generalisability.
B. The 'trustworthiness task' used in the laboratory experiment had low ecological validity.
C. The rating methodology was somewhat artificial as it used a Likert scale rating system, with key terms being 'very
untrustworthy', 'neutral' and 'very trustworthy'. Participants could have differing concepts of what 'trustworthy' is.
D. The researcher's assertion that scepticism or low levels of trust are socially advantageous is not clearly supported.
15. Choose the conclusion that best applies to the findings of Baumgartner et al.'s (2008) study:
A. Oxytocin may decrease fear reactions that may arise as a consequence of human betrayal. B. Oxytocin may increase
feelings of attractiveness between strangers. C. Oxytocin may increase trust in relationships. D. Oxytocin may suppress
the fight or flight response.
TASK
16. Compared to neurotransmitters, do hormones take a longer or shorter time to
affect the body and behaviour? Hint: write either longer or shorter in the answer
box.
17. Baumgartner et al. (2008) investigated the role of oxytocin on trust, after trust
was repeatedly broken in an economic game. Which frequently-researched brain
region beginning with 'a' did the researchers measure activity in?
18. Which hormone plays a role in regulating your heartbeat?
A. Oxytocin
B. Testosterone
C. Adrenaline
D. Cortisol
REFERENCES
• Alexander, G. M. & Hines, M. (2002). Sex differences in response to
children’s toys in nonhuman primates (Cercopithecus aethiops
sabaeus). Evolution and Human Behavior, 23, 467–479.
• Berenbaum, S. A., Martin, C. L., Hanish, L. D., Briggs, P. T., & Fabes, R. A.
(2008). Sex differences in children’s play. In J. B. Becker, K. J. Berkley, N.
Geary, E. Hampson, J. Herman, & E. Young (Eds.), Sex differences in the
brain: From genes to behavior. New York: Oxford University Press.
• Dabbs, J. M. (2000). Heroes, rogues, and lovers: Testosterone and behavior.
Columbus, OH: McGraw Hill.
• Fleming, A. S., & Gonzalez, A. (2009). Neurobiology of human maternal
care. In P. T. Ellison & P. B. Gray (Eds.), Endocrinology of social
relationships (pp. 294–318). Cambridge, MA: Harvard University Press.
• www.kognity.com