Literature Review on Schizophrenia

This literature review explores the biological, psychological, and social factors behind the etiology of schizophrenia. It discusses the impact of brain structure, genetic variants, environmental triggers, social stigma, and medication adherence on the progression and maintenance of the disease.

Running head: LITERATURE REVIEW ON SCHIZOPHRENIA
LITERATURE REVIEW ON SCHIZOPHRENIA
Name of the Student
Name of the university
Author’s note

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Introduction
Schizophrenia is chronic and a cognitive disorder that is characterised by hallucinations,
delusions , thought disorders, avolition, poor expression of the emotions, social withdrawal,
suicidal tendency and other cognitive difficulties that significantly affects the way a person
behaves and believes. It usually appears in the early adulthood or the late adolescent period.
There are generally five types of schizophrenia- paranoid schizophrenia, disorganized, or
hebephrenic schizophrenia, catatonic schizophrenia, childhood schizophrenia and schizoaffective
disorder. In Australia, Schizophrenia affects about 1.5 % of the population. The prevalence of the
disease is more in the migrants than the native born people (Australian government, Department
of health, 2018). 15 % of the people suffering from schizophrenia have had suicidal ideation
frequently (Australian government, Department of health, 2018). Furthermore, there is also a
strong public perception about schizophrenia, that all the schizophrenic patients are violent and
can pose harm to the society.
The most effective available treatment for the schizophrenia involves both medication
and psychological therapy yet there had been recurrent symptoms of schizophrenic episodes. In
order to incorporate appropriate treatment strategies, it is necessary to have an in depth
understanding of the biological, psychological and the social factors responsible for the
symptoms. This literature review aims to explore the above mentioned factors behind the
etiology of the disease.

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Biological factors
Brain structure discoveries in case of Schizophreniua have been noticed with the help of
magnetic resonance imaging (MRI). Volumetric differences in the brain of the schizophrenic
patients have been observed. The volume of the superior temporal gyrus has been noticed in
Schizophrenia and a correlation can be found between the changes in the volume and the
characteristics of the illness (Rees et al., 2016). The medial temporal cortex, including the
entorhinal, hippocampal cortex, parahippocampal and the hippocampal cortex have also shown
reduction in size and the results has been consistent across different laboratories. Karlsgodt et al.,
(2010), have noted that there is a reduced blood flow in the prefrontal cortex in the brain in
schizophrenia and this information served a great deal to develop the future ideas. Recently, the
laboratories have focused on the abnormalities on the anterior cingulated cortex and the
hippocampus of a schizophrenic brain. It is known that a normal brain involves a complexly
interacting neuronal system. There is a long tract pathway between the sub cortical are and the
frontal cortex, through which the basal ganglia affects the functioning of the frontal cortex (Rees
et al., 2016). Since basal ganglia involve a diversity of modulators and neurotransmitters, any
abnormality in the neurotransmitter functioning in the basal ganglia might lead to schizoaffective
disorder. Furthermore, a study examined brain surface contraction in the schizophrenic patients
(Sun et al., 2009). Surface contraction in the prefrontal and a reduction in the grey matter have
been found to be higher in patients than the control group. Apart from the neurological factor,
there are several genetic variants that make substantial contributions to thee this disorder.
A direct observation of the environmental and the genetic factors was demonstrated when
it was observed that fetal hypoxia can be associated with the reduction in the grey matter and
increased cerebrospinal fluid in patients suffering from Schizophrenia. Other free-natal factors

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associated with schizophrenic disorders are low folate, which can lead to the an increased plasma
homocysteine (Rees et al., 2016) . An increased homocystiene imparts a modulatory effect on N-
methyl- D-aspartate (NMDA) receptor, the key component of the gluitamatergic theory of
schizophrenia.
Psychological factors
Certain environmental triggers and discrete events can trigger schizophrenia. Stresses like
loss of parents, partners, disrupted family patterns, rejection, criticism, over involvement, high
anxiety and conflicts at home or with partners might lead to extreme stresses.
Factors like social isolation and high expressed emotions are one of the main cause of
Schizophrenia. Expressed emotions have been found to be a significant predictor of the relapse
of schizophrenia. However, there are very few papers in precipitating the first break in the
psychosis. Jiang et al., (2013), had studied the impact of the environment of the family in the in
the development of schizophrenia and found that lower levels of caregivers emotional
attachment, warmth and remarks is associated with disruptive behavioral pattern in children. A
study conducted by Li et al., (2017), have proved that social isolation leads to a series of
schizophrenic deficit problems such as social withdrawal, cognitive impairment, anxiety
disorder, sensorimotor gating disturbances, Surprisingly, Social isolation has also been linked
with the potential interactions between histidine triad nucleotide binding protein 1 (HINT1), the
NRI subunit of N-methyl-d-aspartate acid receptor, and D2R (dopamine type 2 receptor)
(Mumtaz, Khan, Zubair & Dehpour, 2018). Similarly, a study by Jiang et al., (2013), has
reported that deletion of the N-methyl-D-aspartate receptor (NMDAR) from a subset of
corticolimbic interneurons present in the mouse brain at the time of early postnatal development

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is responsible for triggering several pathophysiological and behavioral features resembling the
symptoms of human schizophrenia and many of the behavioral phenotypes have been found to
be increased due to social isolation (Zhou et al., 2018). Again, Amaresha &
Venkatasubramanian, (2012), have explained the components of expressed emotions like
hostility, critical comments, EOI, warmth and positive remarks that guides one’s behavioural
patterns. A cross-sectional study involving 400 participants had demonstrated that anger,
rejection, ignorance, blaming, irritability and negligence to be the main in house factors for the
development of schizophrenic symptoms.
Social factors
One of the important social factors behind the cause and the maintenance of
schizophrenia is the social stigma, which can cause antipsychotic non-adherence. Despite of the
recent advancements in the treatment of the schizophrenia, those people suffering from
schizophrenia suffers from considerable stigma. Schizophrenic patients often suffer from self-
stigma due to the process of internalization of the stigma. According to Higashi et al., (2016),
people hallucinating with voices and visions often do not want to adhere to antipsychotics as
they want the moments of fantasies to remain forever, or they love to stay in the world of
fantasies. The urge of doing unusual and the exciting things makes them to live in the world of
fantasies, which normally starts fading as the patient starts responding to the treatment. Some
schizophrenic patients might not want to live in the reality and thus do not comply with the
treatment regimen. A study by Read & Dillon, (2013), compared the adherence to medication
between the patients with one mental illness and one somatic illness. Non adherence to
medications was more found in patients with schizophrenic patients. The researchers have found
out the stigmatization, shame and fear of being marginalized prevented them from taking the

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antipsychotics. Many people suffering from schizophrenic symptoms do not stick to the
treatment regimen as most of them wants to conceal it from the society or workplace. This is due
to the fact that in most of the cases people suffering from mental health illness are being
discriminated in terms of terms of job role or remuneration. Higashi et al., (2016), on the other
hand have opined that society pays a great role other than self stigmatization and it is the
emotional responses of the family that decides the antipsychotic adherence.
Effect of all the three integrated factors
As per the literary evidences discussed above, it can be easily perceived that there is a
lack of concrete data or evidences regarding the actual reason behind the symptoms of
Schizophrenia. A large gap can be noticed in the researches associated with the biological
factors. A wide number of researches are still going on to identify the genes associated or the
lobes of the brain involved. However Read& Dillon, (2013) , have opined that unmet needs
during childhood such as the psychological needs might lead to the development of maladaptive
schemas, which in turn designs neurological development in early childhood period. According
to Gejman, Sanders & Duan, (2010), genetic factors like deletion of certain genes are not related
to any king of preformed schema and are solely due to genetic mutations. It has already been
mentioned that folate deficiencies at the time of pregnancy might lead to insufficient neuronal
development causing the cognitive symptoms of schizophrenia. Folate deficiencies can again be
related to lack of proper nutrition at the time of pregnancy, which indicates largely towards poor
socio- economic status (Kirkbride et al., 2012). In relation to this Topor et al., (2014), have
demonstrated that poverty is an important predicting factor of schizophrenia. Poverty has also
been identified as one of the determinants of medical non-adherence. Hence, it is evident, that

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Schizophrenia can be multifactorial depending upon the type of exposure the patient is subjected
to.
Conclusion
The literature review has portrayed a range of biological, psychological and the social
factors behind the progression and the maintenance of the schizophrenic symptoms. Considering
a large number of factors responsible for this condition, this review indicates towards the
adoption of multidirectional approach for treating the symptoms. It can also be understood from
this review that there are still some gaps left in the assessing the actual factors behind the disease
and hence requires larger scopes of further researches. However, proper screening,
pharmacological treatment in collaboration with some strength based alternative approach can
bring about positive patient outcomes.

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Part b
The film that has been chosen for this assignment is “The voices” directed by Marjane Satrapi. It
is a black comedy horror, where Jerry is a schizophrenic patient, who works at a bathtub factory
and lives alone with his pet dog and cat. Jerry does not adhere to his medications as enjoys the
hallucinations where, his pet dog and cat engages in conversation with him and encourages him
to do obnoxious and violent activities. Jerry had a romantic interest for his colleague, but things
turned bad when they were up for a date. Guided by the suggestions of the talking cat, Jerry
ended up murdering his girlfriend. This main story is guided by several moments of fun and
horror.
It should be mentioned that schizophrenic patients are subjected to delusional thoughts
and hallucinations hence the clinical manifestations shown by Jerry in this film matches with the
general signs and symptoms of schizophrenia.
Some of the tasks related to the depiction of the schizophrenia are discussing the stigma.
It has to be noted, that patients suffering from schizophrenia are often marginalized due to the
predetermined notion of violence due to some past experiences (Read & Dillon, 2013). Another
task of depicting the mental illness is to understand the predisposing factors and the precipitating
factors behind the clinical conditions. A range of biological, social and the psychosocial factors
are responsible for this disease.

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References
Amaresha, A. C., & Venkatasubramanian, G. (2012). Expressed emotion in schizophrenia: an
overview. Indian journal of psychological medicine, 34(1), 12-20. doi: [10.4103/0253-
7176.96149]
Australian government, Department of health., (2018). Schizophrenia fact sheets, Australia.
Access date: 4.12,2018. Retrieved from: http://www.health.gov.au
Gejman, P. V., Sanders, A. R., & Duan, J. (2010). The role of genetics in the etiology of
schizophrenia. The Psychiatric clinics of North America, 33(1), 35-66.
[10.1016/j.psc.2009.12.003]
Higashi, K., Medic, G., Littlewood, K. J., Diez, T., Granström, O., & De Hert, M. (2013).
Medication adherence in schizophrenia: factors influencing adherence and consequences
of nonadherence, a systematic literature review. Therapeutic advances in
psychopharmacology, 3(4), 200-218.
Jiang, Z., Rompala, G. R., Zhang, S., Cowell, R. M., & Nakazawa, K. (2013). Social isolation
exacerbates schizophrenia-like phenotypes via oxidative stress in cortical interneurons.
Biological psychiatry, 73(10), 1024-1034. https://doi.org/10.1016/j.biopsych.2012.12.00
Karlsgodt, K. H., Sun, D., & Cannon, T. D. (2010). Structural and Functional Brain
Abnormalities in Schizophrenia. Current directions in psychological science, 19(4), 226-
231. doi: [10.1177/0963721410377601]

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Kirkbride, J. B., Susser, E., Kundakovic, M., Kresovich, J. K., Davey Smith, G., & Relton, C. L.
(2012). Prenatal nutrition, epigenetics and schizophrenia risk: can we test causal effects?.
Epigenomics, 4(3), 303-315. https://doi.org/10.2217/epi.12.20
Li, B. J., Liu, P., Chu, Z., Shang, Y., Huan, M. X., Dang, Y. H., & Gao, C. G. (2017). Social
isolation induces schizophrenia-like behavior potentially associated with HINT1, NMDA
receptor 1, and dopamine receptor 2. Neuroreport, 28(8), 462-469. doi:
[10.1097/WNR.0000000000000775]
Mumtaz, F., Khan, M. I., Zubair, M., & Dehpour, A. R. (2018). Neurobiology and consequences
of social isolation stress in animal model—A comprehensive review. Biomedicine &
Pharmacotherapy, 105, 1205-1222. https://doi.org/10.1016/j.biopha.2018.05.086
Read, J., & Dillon, J. (Eds.). (2013). Models of madness: Psychological, social and biological
approaches to psychosis. Routledge.
Rees, E., Carrera, N., Morgan, J., Hambridge, K., Escott-Price, V., Pocklington, A. J., ... &
Morris, D. W. (2018). Targeted sequencing of 10,198 samples confirms abnormalities in
neuronal activity and implicates voltage-gated sodium channels in schizophrenia
pathogenesis. Biological psychiatry. https://doi.org/10.1016/j.biopsych.2018.08.022
Shrivastava, A., Johnston, M., & Bureau, Y. (2012). Stigma of Mental Illness-1: Clinical
reflections. Mens sana monographs, 10(1), 70-84. doi: [10.4103/0973-1229.90181]
Sun D, Stuart GW, Jenkinson M, Wood SJ, McGorry PD, Velakoulis D, et al. Brain surface
contraction mapped in first-episode schizophrenia—A longitudinal magnetic resonance
imaging study. Molecular Psychiatry. 2009;14:976–986

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Topor, A., Andersson, G., Denhov, A., Holmqvist, S., Mattsson, M., Stefansson, C. G., &
Bülow, P. (2014). Psychosis and poverty: coping with poverty and severe mental illness
in everyday life. Psychosis, 6(2), 117-127.
https://doi.org/10.1080/17522439.2013.790070
Zhou, H. Y., Li, Z., Xie, D. J., Xu, T., Cheung, E. E., Li, H., & Chan, R. C. (2018). Heritability
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Appendix