Passamonti et al (2012) - Techniques to study the brain in relation to behaviour,

Neurotransmitters and their effect on behaviour, Synapse (excitatory/inhibitory),

Agonists and antagonist, Neurons

Passamonti aimed to investigate the effects of serotonin depletion on the brain. The
experimental group consume a drink that lacked tryptophan. Tryptophan is an amino
acid used to build serotonin. Creating a lack of tryptophan in the body can create
reduced levels of serotonin in the brain. On one hand, the control group was given a
drink with normal amounts of tryptophan that did not have any effects on the body.
The participants were put in fMRIs and their brain activity was measured while they
were seeing images of happy, angry or neutral faces. The results show that there
was reduced activity in the frontal lobe during the low serotonin conditions when the
participant was viewing the angry face (a threatening stimulus). Moreover,
communication between the amygdala and the pre-frontal cortex (PFC) was weaker
and disrupted in this case of viewing angry faces with low level of serotonin. To
understand the results, the role of the PFC and amygdala needs to be understood.
The PFC is responsible for regulating impulsive behaviour, and the amygdala in
regulating emotion and the stress response. The disruption of brain activity in these
two areas has created a lack of activity in the PFC, which may affect the individual's
ability to regulate the stress response as triggered by the amygdala’s reactivity
towards the threat. So, when an individual has high levels of emotion and low levels
of rational thinking as a result of low serotonin levels, it is more likely for them to act
on their impulsive behaviours, thereby eliciting aggression.

Dragenski et al (2004) – Neuroplasticity, Neural networks, Neural pruning

The aim of the study was to investigate the relationship between learning a new skill
and the structure of the brain. The study used 24 participants with an average age of
22 years old. All participants were non-jugglers at the start of the study and each
participant had an MRI scan at that time. Participants were allocated to one of two
conditions - the jugglers and the non- jugglers. Those that were in the juggling
condition were taught a three-ball cascade juggling routine. They were asked to
practice this routine and to notify the researchers when they had mastered it. At that
point the jugglers had a second MRI scan. After the scan, they were told not to
juggle anymore and then a third and final scan was carried out three months later.
The non-juggling group served as a control group for the duration of the study. To
analyse the MRI scans, the researchers used voxel-based morphometry [VBM] to
determine if there was significant differences in neural density (grey matter) in the
brains. The found that the jugglers showed a significantly larger amount of grey
matter in the mid- temporal area in both hemispheres - an area associated with
visual memory. Three months after the participants stopped juggling - and many
were no longer able to carry out the routine – the amount of grey matter in these
parts of the brain decreased. The finding of the experiment can be understood by
incorporating the role of the temporal lobe and the concept of neuroplasticity.
According to the localization of function, the temporal lobe is responsible for visual
memory, which is needed the in practicing of juggling. As the participants learn a
new skill (juggling), new neural connections with synapses are formed, which leads
to an increase in grey matter in the temporal lobe. As the participants stopped
practicing the skill, those newly formed neural connections are weakened to ensure
the efficiency in other areas of the brain. The trend of increasing then decreasing of
brain matter based on whether or not the participants are practicing the skill shows
that the brain has the ability to re-organize itself based on environmental stimulus.
The study demonstrates that the temporal lobe may change in response to
environmental demands (in this case learning a new skill).
Scheele et al (2012) – hormones - oxytocin

Oxytocin modulates social distance between men and women. Scheele’ study aims
to investigate the role of oxytocin in promoting fidelity in humans. Participants
consisted of 86 heterosexual men, some single and some in a stable relationship.
The study was an experiment and followed an independent measures design. The
participants were intranasally administered with either oxytocin or placebo. After this,
participants were required to engage in two tasks. The first task was a Stop-distance
paradigm where the participant stood at one end of the room and an attractive
female confederate stood at the other end. Participants were instructed to slowly
approach the female confederate and stop at a distance that made them feel slightly
uncomfortable. The second task was an approach/avoidance task where participants
were positioned in front of a screen. They had a joystick and were then shown a
series of pictures of four types, in random order: positive social pictures, positive
non-social pictures, negative social pictures, negative non-social pictures. If the
participant liked the picture, he had to pull the joystick, increasing the size of the
picture. If he did not like the picture, he had to push the joystick, making the picture
smaller. The findings of the study demonstrated that the first task showed that
oxytocin caused men to keep a greater distance from the attractive female
confederate, but only if the man was in a stable relationship. Results of the second
task showed that the only group of pictures affected by oxytocin and relationship
status was the positive social group. Men in a relationship pulled the joystick more
slowly in the oxytocin condition but not in the placebo condition. This demonstrates
that oxytocin causes men in a relationship to keep a greater distance from attractive
women who are not their partner. Researchers explained that this promotes fidelity.
The second task makes it evident that this effect of oxytocin is highly specific and
selective to a certain group of stimuli that is attractive women.

Lundstrom and Olsson (2005) - Pheromones

Being exposed to androstadienone increases the mood of women in the presence of

a male experimenter, which suggests that this chemical may trigger attraction.
The aim of this study is to investigate the effect of androstadienone on the mood of
women in the presence of men. A total of 37 heterosexual women, mean age 25
years, with a normal menstrual cycle were chosen as participants for this study. This
study is an experiment and follows a 2x2 experiment design (two independent
variables with two levels each). In this study the mood of female participants’ was
studied after being exposed to either androstadienone or a control solution, and in
the presence of either a male or a female experimenter. The experimenter carried
out a number of measurements including several questionnaires. One of the
questionnaires measured participants’ mood. The experimenter was either female
(age 28) or male (age 30). The finding of this study presented that androstadienone
increased women’s mood in the presence of a male experimenter, but not a female
experimenter. This demonstrates that Androstadienone may serve the function of
signalling sexual attractiveness, which supports its role as a pheromone.
Bouchard and McGue (1981) – Genes and behaviour

Genetic inheritance study the inheritance of patterns of behaviour determined by

genes. It is the process in which genes segments of DNA are inherited or passed down
from parents to offspring. Genes are considered to be responsible for development of
behavioural characteristics. Genes are inherited from their parents as well as the
environment around them. In humans, this information is often gathered through the
use of twin studies or adoption studies. Because identical twins share identical genes
therefore, twin studies provide an effective way of isolating the effect of genes as well
as effect of environment on behaviour. However, Inheriting certain genes may be at
risk of some mental disorders such as depression.

An example of a twin and kinship study is a study conducted by Bouchard and McGue
(1981). The study aims to determine the degree of heritability of intelligence levels, of
IQ. The study was a meta-analysis of 111 studies that included both MZ twins, DZ
twins, and siblings that are reared together or apart. The results showed that the
individuals that had a closer kinship had a higher median correlation in intelligence
levels with each other. For instance, MZ twins that are reared together (they have
100% similarity in genetics and shared environment) have a 0.85 median correlation
value, while MZ twins that are reared apart had a value at 0.67. Siblings that only had
50% genetic similarity had a lower correlation value, with dizygotic twins reared
together coming at the third and sibling reared apart value being the lowest. Their
meta-analysis also yielded the heritability of intelligence to be 54%, based on
calculation using the Falconer model. The study demonstrates that intelligence is
inherited to a considerable extent. The 54% value indicates that intelligence is half
determined by genes and half determined by environmental influence. Even though
genes do play a role in affecting intelligence, IQ is not completely inherited, as even
with MZ, their median correlation is not perfect. This shows that environment also
play a role in influence intelligence levels.

Localization

At the time of the first study by Milner, HM was 29 years old. He was a
mechanic who had suffered from minor epileptic seizures from when he was
ten years old and began suffering severe seizures as a teenager. These may
have been a result of a bike accident when he was nine. His seizures were
getting worse in severity, which resulted in HM being unable to work.
Treatment for his epilepsy had been unsuccessful, so at the age of 27 HM
(and his family) agreed to undergo a radical surgery that would remove a
part of his brain called the hippocampus. Previous research suggested that
this could help reduce his seizures, but the impact it had on his memory was
unexpected. The Doctor performing the radical surgery believed it was
justified because of the seriousness of his seizures and the failures of other
methods to treat them.

In one regard, the surgery was successful as it resulted in HM experiencing

less seizures. However, immediately after the surgery, the hospital staff and
HM’s family noticed that he was suffering from anterograde amnesia (an
inability to form new memories after the time of damage to the brain):

Here are some examples of his memory loss described in the case study:

 He could remember something if he concentrated on it, but if he broke

his concentration it was lost.
 After the surgery the family moved houses. They stayed on the same
street, but a few blocks away. The family noticed that HM as
incapable of remembering the new address, but could remember the
old one perfectly well. He could also not find his way home alone.
 He could not find objects around the house, even if they never
changed locations and he had used them recently. His mother had to
always show him where the lawnmower was in the garage.
 He would do the same jigsaw puzzles or read the same magazines
every day, without ever apparently getting bored and realising he had
read them before. (HM loved to do crossword puzzles and thought
they helped him to remember words).
 He once ate lunch in front of Milner but 30 minutes later was unable
to say what he had eaten, or remember even eating any lunch at all.
 When interviewed almost two years after the surgery in 1955, HM
gave the date as 1953 and said his age was 27. He talked constantly
about events from his childhood and could not remember details of his
surgery.

Later testing also showed that he had suffered some partial retrograde

amnesia (an inability to recall memories from before the time of damage to
the brain). For instance, he could not remember that one of his favourite
uncles passed away three years prior to his surgery or any of his time spent
in hospital for his surgery. He could, however, remember some unimportant
events that occurred just before his admission to the hospital.
Multi store memory model

The Multi-Store Memory Model (MSM) proposed by Atkinson and Shiffrin aims to explain the
mechanism of memory storage (encoding, storage, and retrieval). The Multi-store memory model
assumes that memory is sequential (flows unidirectionally from one store to another) and that different
memories function in a uniform fashion, being stored separately. The model is being separated to 3
storages: sensory memory, short term memory (STM) and long-term memory (LTM). The sensory
memory receives and temporarily stores sensory information in an unprocessed from. It can only be
transferred to STM for conscious recall when attention is being allocated to it. The short-term memory
has the capacity of 7 plus/minus 2 chunks of information and 15 seconds duration according to Milner.
According to the model, STM can only be encoded into LTM when it is being constantly repeated, this is
called rehearsal. When there are new information or tasks that prevented the process of rehearsal, the
memory is displaced and will be lost (displacement decay). The duration and capacity of LTM is not
established yet, but it potentially has unlimited capacity and duration.

Glazer and Cunitz (1966) –

Multi store memory

The Multi-Store memory

model is supported by Glazer
and Cunitz's study. The
researchers read a list of 15
words to participants and asked
them to recall the words in any
order. Before they did this, the
researchers randomly allocated
participants to one of three
conditions. The words were
read one at a time and then the participants were either asked to recall the words immediately after the list
was finished, with a 10-second delay or with a 30-second delay. During conditions with delays, the
participants were asked to count backwards from 100. When there was no delay, they found that
participants remembered the first few words and the last few words on the list. In the 10 and 30 second
delay condition, the participants mostly remembered the first few words on the list. The results of the
experiment showed that the primacy and recency effect was present in the control group. The primacy
effect, meaning that participants mostly remembered words from the beginning of the list, showed that
through constant rehearsal, the information was already transferred to LTM and was therefore memorized
and stored for a longer period of time, allowing it to be retrieved from LTM back to STM to be recalled.
The recency effect, which means that words at the end of the list was remembered, was due to the fact
that the words were temporarily stored in STM and can be immediately recalled within 15 seconds. In the
experimental group, the recency effect disappeared (more in the 30 seconds condition than the 10 seconds
condition), because the recency effect was displaced by the filler task engaged, causing displacement
decay of the STM. This shows that through rehearsal words at the beginning of the list had been placed in
LTM, but counting backwards had displaced the information of the last few words on the list in STM.
The fact that the inclusion of a filler task results in disappearance of recency effects but not primacy
effect supports the idea that STM and LTM are two separate memory stores.

Working Memory Model

The Multi-store memory model explains that memory flows in one direction; however,
the Working Memory Model challenged the Multi-Store memory model by suggesting
that STM is more complex than that. The Working Memory Model attempts to explain
how small amounts of information is held in mind temporarily and used in the
execution cognitive tasks. The model suggests that the individual's attention is
monitored by the central executive and that it controls three separate short term
memory (STM) storages: the visuospatial sketchpad, phonological loop, and the
episodic buffer. The visuospatial sketchpad holds visual information, while the
phonological loop stores auditory information in either verbal form in the articulatory
control system (inner voice) or in a passive, memory trace form through the
phonological store (inner ear) until it is recalled again. The episodic buffer can hold
several sources of information at the same time temporarily to form integrated units
of auditory and visual information, as well as information from long term memory
(LTM). This model explains why humans can multitask sometimes, as it suggests
that we can only multitask when the information is encoded under different memory
mechanisms, that is the visuospatial sketchpad and the phonological loop.

Laundry and Bartling's (2011)

The Working Memory Model is supported by Laundry and Bartling's (2011) study,
which aims to investigate if articulatory suppression would influence the accuracy of
recalling a list of letters. The study implemented independent measures design with
34 undergraduate psychology students. The participants were given 5 seconds to
read a list of 7 letters. The control group can recall the letters by writing them on a
piece of paper 5 seconds after memorization. In the experimental group, the
participants were instructed to say the numbers 1 and 2 at the rate of two numbers
per second while memorizing the list of letters and in the five seconds time frame.
The additional instruction of saying the numbers was present to create articulatory
suppression, to create overload to the phonological system by providing a
concurrent task. Each participant repeated the experiment 10 times in total. They
were scored based on the accuracy of recall, and the results were averaged to
compare control and experimental group. The results were that the accuracy of recall
for the experimental group was much lower than the control group (45% comparing
to 76% accuracy). This result support The Working Memory Model, in which that an
individual cannot multi-task when it involves the same memory storage, the
phonological loop in this case, as the inner voice is required to repeat the sensory
information to encode the memory. Hence, an overload to the rehearsal system
prevents rehearsal and the formation of STM. Even through the memorization of a
list of letters is not realistic in real life situation, but this this case the addition of the
articulatory suppression task does resemble the dual task technique. An issue with
this study was that the participants were psychology students, which demand
characteristics including the expectancy effect may be present among the
participants to predict the aim and patterns of the results.

Anderson and Pichert (1978) – schema theory

Anderson and Pichert (1978) aimed to investigate if schemas influence the encoding and
retrieval stage of memory. In their study, the subjects were given a role of a burglar or a
house buyer. The subjects then had 2 minutes to read a passage about what two boys were
doing at a home while they were skipping school. The story contains 72 points of details
about the house, which some were rated more of an interest to a burglar than a house buyer,
and vice versa. After a 2-minute reading time, the participants performed a 12-minute filler
task, before the story was recalled. Data was collected via giving the participants blank
papers and have them reproduce the story as much as possible. After the first recall, another
5-minute filler task was given. For the second round of recall half of the participants were
instructed to switch to the alternative perspective and recall the text for a second time without
reading it again. The results showed that in the first round
of recall, the participants who had a burglar perspective recalled more information relevant to
their perspective, and it was the same with the home buyer's perspective. In the second round
of recall, participants who changed roles recalled 7% more points on the second recall test
than the first, and those details are rated more important to new perspective. The group that
remained in the same role, had a decrease in the number of details recalled. This study
showed that people retrieved different information based on the their schemas that were
activated based on the perspective given to them. On the second round of recall, those who
had buyer schema at encoding were able to recall burglar information when an alternative
schema was activated. This showed that schemas did not affect the encoding stage of
memory, because the participants did not read the passage for a second time, so before the
switch in perspective, the piece of information more relevant to the burglar perspective was
already encoded but had not been retrieved. This showed that schemas influence the process
of retrieval of already stored information from memory. The participants who did not switch
role recalled less details over time due to displacement degradation of short-term memory
from the filler task. In conclusion, Schema processing has an influence at only at the retrieval
stage.

Brandsford and Johnson (1972) – schema theory

Essential understanding
✪ Providing a full context prior to an unfamiliar text
passage leads to better recall of the idea units contained
in this passage. Arguably, this happens because a mental
representation (schema) is created and the new ideas are
then linked to this schema, making encoding more effective.
Aim
To investigate the effect of context on comprehension and
memory of text passages.
Method
Experiment; independent measures design.
Participants
50 male and female high school students who volunteered
to participate in the experiment.
Procedure
Participants heard a tape-recorded passage and were
required to recall it as accurately as they could, writing down
as many ideas as possible. The passage was as follows.
If the balloons popped, the sound wouldn’t be able to carry
since everything would be too far away from the correct
oor. A closed window would also prevent the sound from
carrying, since most buildings tend to be well insulated.
Since the whole operation depends on a steady ow of
electricity, a break in the middle of the wire would also cause
problems. Of course, the fellow could shout, but the human
voice is not loud enough to carry that far. An additional
problem is that a string could break on the instrument.
Then there could be no accompaniment to the message. It
is clear that the best situation would involve less distance.
Then there would be fewer potential problems. With face to
face contact, the least number of things could go wrong”.
(Bransford, Johnson 1972)
There were ve conditions (groups of participants).
• No context (1): participants heard the passage once.
• No context (2): participants heard the passage twice.
• Context before: prior to hearing the passage participants
were given a context picture.
• Context after: the context picture was given after
participants already heard the passage.
• Partial context: participants were given a context
picture prior to hearing the passage, but the picture
only contained the elements mentioned in the passage
without showing how they operate together.

Barrett (1932)
Support for the influence of schemas on cognitive processes is widespread. Bartlett (1932) demonstrated
how schema, specifically cultural schema, can influence memory in his classic study. He gave participants
a complex and unusual story called ‘The War of the Ghosts' which contained unfamiliar supernatural
concepts and an odd, causal structure to Western participants.
• He asked them to recall it six or seven times over various retention intervals. He found that recalled
stories were distorted and altered in various ways making it more conventional and acceptable to their
own cultural perspective. He used the term rationalization to refer to this type of error - rationalizing it
according to what fitted with their existing cultural schemas - for example canoe was often substituted
for 'boat'.
• HOWEVER, the ecological validity of the War of the Ghosts lab study has been questioned. Whilst
Bartlett rejected the artificiality of traditional stimulus such as nonsense syllables ( Ebbinghaus) and word
lists to test memory, his use of a native American folk tale was " about as similar to normal prose as
nonsense syllables are to words ".