Schizophrenia is a devastating and costly mental disorder that affects 1% of population worldwide. Patients manifest clusters of positive, negative and cognitive symptoms in early twenties and are often left with life-long severe mental disability and social stigma. Cognitive deficits in patients with schizophrenia are considered core symptoms of this disorder, and can manifest at the initial stage (Elvevåg and Goldberg, 2000). Atypical antipsychotics ameliorate positive symptoms but may only modestly improve cognitive symptoms (Richelson, 2010). In addition to this, some of the typical antipsychotics are even have deteriorative effects on cognitive symptoms (Heaton and Crowley 1981). To find the appropriate treatments for cognitive deficits of schizophrenia, it is important to know the underlying pathophysiology.
Cognitive deficits in schizophrenia affect ‘executive functions’ which involves working memory, reasoning and task flexibility (Cho et al., 2006). Executive function like ‘set-shifting’ refers to the ability to modify the ongoing behavior in response to a change in strategies to achieve the goal (Floresco et al., 2008). Literature suggests that different neurotransmitters are involved in the pathophysiology of cognitive deficits in schizophrenia.
From long time, dopaminergic hypothesis of schizophrenia has got importance because of increased dopaminergic activity in subcortical brain areas associated with the positive symptoms of schizophrenia. In contrast to increased dopaminergic activity in the subcortical area, evidence indicates that dopaminergic activity is decreased in the prefrontal cortex in schizophrenic patients (Perlstein et al., 2001). Reduction in dopaminergic D1 receptors and density of dopaminergic fiber...
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...chizophrenia is not clear. We ask whether these abnormalities emerge simultaneously or one precedes remaining or they appear in combination. Impaired ability to shift intuitive attentional set forms a core feature of schizophrenic illness and it is associated with prefrontal cortical abnormality. To assess the executive functions in rats, we will be using ‘set-shifting’ task. Set-shifting task requires rats to learn visual-cue discrimination, and then, shift to a response discrimination strategy to obtain a reinforcer (sucrose pellet). Our preliminary results show that control rats take ~75 trials to reach the successful performance criterion in the set-shifting task. We predict that rats infused with GABA, dopamine and/or glutamate antagonists in the prilimbic cortex will require a greater number of trials than the control rats to reach the performance criterion.
Schizophrenia: From Mind to Molecule. Washington, DC: American Psychiatric Press. Kalat, J. (2004). Biological Psychology.
-Lieberman JA, Stroup TS, McEvoy JP, Swartz MS, Rosenheck RA, Perkins DO, Keefe RS, Davis SM, Davis CE, Lebowitz BD, Severe J, Hsiao JK. Effectiveness of antipsychotic drugs in patients with chronic schizophrenia. N Engl J Med. 2005. Web.
Mental illnesses are diseases that plague a being’s mind and corrupts one’s thoughts and feelings. Schizophrenia is one of the many disastrous illnesses that consume one’s life, is known as a real disease that deserves much attention. Experts believe that what causes the illness is a defect in the gene’s of the brain, and little signs of schizophrenia are shown until about one’s early adult years. Some effects of schizophrenia can either be negative or positive, but even if the effects could be either one, people should still be aware that there is something puzzling and alarming happening in the mind of a schizophrenic patient.
Schizophrenia has been defined as a mental disorder characterized by a breakdown in mental thinking and a poor emotional response. This disorganization hasn’t till now acquired a clear understanding of the mechanisms that lie behind (Harrison 1999) but researchers suggest an increase in the dopaminergic transmission in the prefrontal cortex coupled to an inhibition of the glutamatergic pathways, majorly at the level of NMDA receptors (Wen-Jun Gao). For more than 50 years, the dopamine hypothesis had been considered the mother of the theories of schizophrenia. Van Rossum first proposed it in 1966 suggesting that a hyperactivity occurring at the level of the mesolimbic dopamine pathway is the mediator of positive symptoms of schizophrenia (Seeman 1987). More research has flaunted a hypoactivity in the mesocortical dopamine pathway, which has been hypothesized to mediate the negative, cognitive, and affective symptoms of schizophrenia (Knable & Weinberg 1997; Tzschentke 2001). However, in the past two decades, hypotheses of schizophrenia focused less on the already established facts of the hyperactivity of mesolimbic dopamine neurons and under-activity of the mesocortical dopamine neurons. A major hypothesis of schizophrenia digging, to a certain extent, far from dopamine proposes that a combination of genetic factors converge on the N-methyl-D-aspartate (NMDA) receptor of the excitatory neurotransmitter glutamate, leading to neurodevelopmental abnormalities in glutamate synapse formation and ultimately resulting in the observed hypofunction at the level of NMDA receptors. Knowing that NMDA receptors regulate dopaminergic neurons, the decreased activity of NMDA receptors may be involved in the abnormal dopamine activity associated ...
According to Gamble and Brennan (2000), the effectiveness of medication for schizophrenia to relieve patients from psychotic symptoms is limited. Although patients have adequate medication, some received little or no benefit from it and almost half of them still experience psychotic symptoms. They are also more likely to suffer relapse (Gamble and Brennan, 2000). Furthermore, Valmaggia, et al. (2005) found that 50% of patients who fully adhere to anti-psychotic medication regimes still have ongoing positi...
Schizophrenia is a disease that has plagued societies around the world for centuries, although it was not given its formal name until 1911. It is characterized by the presence of positive and negative symptoms. Positive symptoms are so named because of the presence of altered behaviors, such as delusions, hallucinations (usually auditory), extreme emotions, excited motor activity, and incoherent thoughts and speech. (1,2) In contrast, negative symptoms are described as a lack of behaviors, such as emotion, speech, social interaction, and action. (1,2) These symptoms are by no means concrete. Not all schizophrenic patients will exhibit all or even a majority of these symptoms, and there is some disagreement in the psychiatric community as to the exact diagnostic criteria. In addition, there is a great deal of debate as to the causes of the disease. While some proposed causes have been proven false, such as bad parenting and poor will power (2), there are many theories that remain. One of the most famous and most debatable is the dopamine hypothesis. The proposed hypothesis states that the brain of schizophrenic patients produces more dopamine than normal brains. It is this increased dopamine that is believed to be responsible for the symptoms of the disease. However, the is much debate in the scientific community as to the exact mechanism by which altered dopamine levels, especially in the prefrontal cortex, striatum, and limbic system, produce schizophrenia. There is much clinical evidense that provides support for the dopamine hypothesis. The first evidense that dopamine may be involved in schizophrenia came from amphetamine users. Amphetamines work by causing the brain to produce mo...
There are so many types of mental illnesses that affect people every day. When some people think of mental illnesses they think of the ones that would cause people to have physical symptoms as well, but that’s untrue, there are many more that you would never know anyone has if you were to see them on the street. As defined by the 2008 encyclopedia “a mental illness is any disease of the mind or brain that seriously affects a person’s ability or behavior. Symptoms of a mental illness may include extreme moods, such as excessive sadness or anxiety, or a decreased ability to think clearly or remember well.” A mentally ill person has severe symptoms that damage the person’s ability to function in everyday activities and situations. Every nation and every economic level can be affected by a mental illness. In the United States alone about 3% of the population has severe mental illness and to add to that number about 40% of people will experience a type of mental illness at least once in their lives. Some cases of mental illnesses can go away on their own, but some cases are so severe that they require professional treatment. There is so much more available to help people recover from their symptoms than in the past.
One of the most prominent ideas is the "dopamine hypothesis." The dopamine hypothesis attributes hyperdopaminergic function, meaning an excess of dopamine at certain synapses, as a possible cause of schizophrenia (Fann, W.E., Karacan, I., Pokorney, A.D., & Williams, R.L., 1978). Dopamine systems arise from two primary midbrain clusters, the ventral tegmental area and the substantia nigra which have discrete projections to mesolimbic, mesocortical, and striatal regions of the brain. The neurochemical anatomy of dopamine differs in cortical and striatal regions, and it appears that dopamine concentration, receptor regulation, and D2 receptor density varies greatly between striatal and extrastriatal regions (Jones, & Pilowsky, 2002). It is supposed that the therapeutic actions of antipsychotic drugs are exerted via the mesolimbic and mesocortical dopamine pathways in the brain
Classical antipsychotic treatments are commonly used to treat schizophrenic patients with major positive symptoms of schizophrenia, such as Thorazine, Haldol, and Stelazine (Gleitman et al., 2011). Antipsychotic treatments are usually administered with a variety of psychosocial treatments including social skills training, vocational rehabilitation, supported employment, family therapy, or individual therapy (Barlow & Durand, 2014). This is to reduce relapse and help the patient improve their skills in deficits and comply in consuming the
African Americans have a unique relationship with the clinical disorder schizophrenia. Schizophrenia is more frequently diagnosed among African Americans than white Americans or any other racial or ethnic minority in the United States (Neighbors, Trierweiler, Ford & Muroff 2003). The reasons for this are complex and not fully understood. Because of this there is a considerable suspicion and mistrust of psychological care within the black community. Clinicians should take particular precaution in the diagnosis and treatment of African Americans.
National Library of Medicine, National Institute of Health. Schizophrenia. 31 Jan 2013. Web. 15 May 2014
Schizophrenia is a devastating mental disorder that strikes teens and young adults crippling their brain and fragmenting their mind. Victims of schizophrenia remain in endless mental agony constantly confused and in terror. They suffer constantly from hallucinations, delusions, and paranoia. Approximately 1% of the world population live with this disorder making it one of the most common mental disorders in the world. Despite the numbers, there is no known cause or cure for schizophrenia. So what is the disorder, why is it so hard to eliminate, and why do so many people fall victim to the fragmented mind?
The brain, a component of the nervous system that is located in our skulls is a complex organ that determines almost everything about us, from actions to personality traits. It controls voluntary movement, conscious thinking, language, memory, and emotion (“Brain” 2014). Through the use of brain imaging technologies, psychologists are able to break down the complexity of the active brain and study its particular processes. Such technologies include Positron Emission Topography (PET), Magnetic Resonance Imaging (MRI), Functional Magnetic Resonance Imaging (fMRI), Electroencephalogram (EEG), and Computerized Axial Tomography (CAT). These instruments are useful in the field of neurology, but have their own set of benefits and drawbacks depending on different situations. Hence, this essay will discuss and evaluate the brain technologies of PET and fMRI in its role of investigating the relationship between biological factors and behavior in terms of schizophrenia.
Cognitive deficits represent a particularly important point of intervention for the treatment of schizophrenia, a debilitating psychiatric disease that affects approximately 1% of the population (McGrath et al., 2008). These deficits are present in unmedicated (Saykin et al., 1991) and first episode patients with schizophrenia (Bilder et al., 1991; Hoff et al., 2005). Cognitive deficits are present throughout the lifetime of a patient with schizophrenia (Aylward et al., 1984) and remain stable through at least 10 years of illness (Hoff et al., 2005). Amelioration of the cognitive deficits, more than positive and negative symptoms, predict a satisfactory functional outcome in terms of full time employment and therefore represent an important target for therapeutic intervention (Green, 1996; Green, 2006). However, current typical antipsychotics generate little if any improvement in cognitive deficits in schizophrenia and therefore novel compounds are needed as indicated by the initiative sponsored by the National Institute of Mental Health called Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) (Keefe et al., 2007; Young et al., 2009).
Mental health refers to the state of individuals psychologically, emotionally and socially. Mental health affects a person’s emotions, feelings, thoughts, and sections when exposed to different situations. Furthermore, mental health is responsible for a person’s reaction to stress and other social conditions. Generally, mental health affects how a person relates to others and their ability to understand and interact with them. Therefore, problems that affect a person’s mental health affect the abilities to socialize, their feelings, moods, reaction to situations. The person experiencing mental health problem may portray different behaviors when confronted with different issues. Mental health issues have several