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Premorbid Cognitive Deficits in Schizophrenia and Depression

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Depression is an illness that affects a person’s thoughts, mood, and even physical health. Depression is described as having feelings of overwhelming sadness, emptiness, and worthlessness. Depression can become severe enough that it begins to interfere with a person’s work, relationships, and even their willingness to live. The study that has been chosen for the topic of this paper is one that uses the clinical psychology research approach. According to the (ABPP) American Board of Professional Psychology (2012), Clinical Psychologists are professionals that provide services such as treatments, preventions and evaluations of people with behavioral disorders. This type of psychology also offers services as far as assessment and diagnosis (ABPP, 2012). I have chosen this topic to try to better understand the reasons that some people become so overwhelmed by the illness of depression. I have had a sister die of a drug overdose, she was a heavy drug user both of prescription and illegal drugs, and also a severe alcoholic, I believe that a lot of this had to do with her being in a depressed state, that happened after the death of her husband, so with this being said.

I would like to understand the differences in depression disorders how to identify them and the best way to treat them. There are several types of depression that can affect person’s life, the first step is to identify the symptoms, next what could have caused of the illness, then figure out the best treatment for that individual person, which may be with medication or therapy, or both. The study I have chosen to critique is “Static and Dynamic Cognitive Deficits in Childhood Preceding Adult Schizophrenia: A 30-Year Study” the study was done by Reichenberg, Caspi, Harrington, Houts, Keefe, Murray, & Moffitt (February, 2010) in The American Journal of Psychiatry. This study talks about recurrent depression and also schizophrenia. The actual Dunedin Study has several sub-studies and has been an on-going study for over thirty years. The study was done on premorbid cognitive deficits in schizophrenia, in other words it is a study based on what happens before the diagnosis of schizophrenia. Some of the questions that where answered in the studies are: “What is their developmental course? Do all premorbid cognitive deficits follow the same course? Are premorbid cognitive deficits specific to schizophrenia or shared by other psychiatric disorders?” (Reichenberg, Caspi, Harrington, Houts, Keefe, Murray, & Moffitt, February, 2010). Literature Review

The problem with this study is that it seems to be very one sided. There is nothing mentioned about other things that could lead to the cognitive declines in these children. There is nothing mentioned about their childhood environment, as far as upbringing or history of genetic factors. The researches do however mention that they are from a full range of socioeconomic status levels, but they are mostly Caucasian which is another downfall of the study, because race should have been a factor in s study such as this. According to Bresnahan, Begg, Brown, Schaefer, Sohler, Insel, Vella, & Susser, (2007), in a study that they had done the results showed that African Americans are three times more likely to be diagnosed with schizophrenia than whites.

The participants that were part the Dunedin study it is known that this study has been going on for over thirty years. The information in this study is reported by either the children, the parents or they are observed by the researchers, there is nothing included in the data about any common harmful or unpleasant experiences, for example, if any of the family members were alcoholics or of there were any mental or physical abuse. There has been many papers published that explains how early trauma such as this can have lasting effects on the brain and also the body of the child. This trauma can become a tortuous pathway that our brain comes up with to help us deal with the reaction to these stressful events. This pathway helps us produce emotions like anxiety and even fear, and also physical reactions for example, an increase in blood pressure, heart rate or we even may become sweaty. This study takes none of this into consideration.

There is however, another sub-study that suggests that the use of cannabis in the teen years will increase the risk of developing schizophrenia as an adult (Leask, 2004). A researcher named Arseneault, had already done a study on the effects of cannabis and the increased risk of developing adult schizophrenia, (Leask, 2004). In Arseneault (2004) study there was the controlling of earlier psychotic symptoms that could have possibly influenced by both the cannabis use and the on-set of the schizophrenia. The results of this study were that individuals did show that the use of cannabis doubles the risk for the development of schizophrenia (Arseneault, Cannon, Witton, & Murray, (2004). The researchers also report that at a population level if the cannabis is taken out of the equation and 8% decrease in the occurrence of developing schizophrenia assuming a causal relationship (Arseneault, Cannon, Witton, & Murray, (2004). In other words, psychotic disorders could be prevented if youths would not use the cannabis, so now we need to understand why the cannabis causes the psychosis. This is only the beginning to the problems that were ignored in this study. Methods

This is a qualitative study with what this researcher would say would be a quasi-experimental design, because in this type of design there is no random pre-selection process used in the study. There were 1,037 participants both male and female, they were members of a cohort, which according to Business Dictionary.com (2012) is a group that shares an experience at a certain period of time or they can also share one or more of the same characteristics, in this case all of the participants were born in Dunedin, New Zealand between 1972 and 1973. This study was over a 30 year span and the participants went through evaluations at certain periods from ages 3 to 32 years of age. The researchers later compared the data of the children who developed schizophrenia or some sort of depression as adults (Reichenberg, Caspi, Harrington, Houts, Keefe, Murray, & Moffitt, 2010). WISC-R

Some methods of testing these children were that within one month of the children’s birthdays at the ages of 7, 9, 12, and 13 years of age they were given the Wechsler Intelligence Scale for Children-Revised (WISC-R) test. The test is designed to do a complete measurement of a child’s cognitive ability (nova.edu, n.d.). The researchers were not aware of the results of the tests that were administered previously. The children were given eight sub-tests based on verbal comprehension, which evaluates a child’s understanding of the language through the receptive mode for example listening or reading, perceptual organization, (these test helps look at how a person understands or sees the world around them), and freedom from distractibility, (these tests try to look at the child’s ability to concentrate and to stay focused). There was a total of four of the sub-test omitted two because they were not part of the IQ and the other two because of the time constraints. The tests that were not given were mazes, digit span, comprehension and picture arrangement.

According to Banas, & Willis (1978), the mazes of the WISC-R are to measure planning ability and perceptual organization. Digit scan is another of the subtests that were omitted in the study when testing the children’s I.Q. Digit scan measures attention, concentration, and immediate memory this could have been an important factor because lower scores are signs of attention deficit or anxiety (Rich, 2011). Then we have comprehension, this sub-test measures social conversation and common sense, which might also be an important factor, especially the common sense factor. The final sub-test that was omitted was picture arrangement this sub-test requires the pictures to be placed in order to tell a story, the test measures things like nonverbal social interaction, and the ability to reason chronologically (Rich, 2011). This researcher believes that any of these factors could have changed the results of this study in both a positive and a negative way(s). Mental Age

As far as the mental age a normal child would be expected to increase in the WISC-R scores as they increase in age. The researchers translated these raw scores into mental age scores this was done using a regression model that was found in the WISC-R manual. According to Reichenberg, Caspi, Harrington, Houts, Keefe, Murray, & Moffitt (2010) mental age scores tell us what the chronological age for a certain level of functioning should be so we can better tract and monitor child’s development over a period of time. In other words these IQ and the subtests are used for comparing a child to others in a population of the same chronological age. Assessment of Schizophrenia Spectrum Disorder and Depression Schizophrenia

In this phase of the study, the schizophrenia was assessed at the age 21 follow-up examination. If there was any possibility that the participant had the illness before this examination they were entered into the group referred to as “schizophreniform” or “schizophrenia syndrome” because of the ages and that they were diagnosed in a hospital setting just a research diagnosis, (Reichenberg, Caspi, Harrington, Houts, Keefe, Murray, & Moffitt, 2010). According to Reichenberg, Caspi, Harrington, Houts, Keefe, Murray, & Moffitt (2010), they developed special qualifications to be diagnosed in a research setting. They required the person to have hallucinations that were not drug related and at least two other positive symptoms. The study also reports that these are stricter requirements than the actual Diagnostic and Statistical Manual of Mental Disorders fourth edition (DSMIV) norms for the illness. The DSMIV does not require hallucinations to be present for a diagnosis and also they did take into consideration that a lot of this study was based on self-reporting. However this researcher believes that if a participant was thought to have had schizophrenia then that participant should have been referred to a place of treatment, not just assumed to be ill.

Even though there were some interviewing by the researchers and the parents of these children does not 100% validate the data that was received, and also it is reported in the study that participants did bring in medications that were classified by a pharmacist but there is no place in the study where the medications are taken into consideration. There were follow-ups done at the ages of 26 and 32 and by then 1% of the sample had been formally diagnosed, been hospitalized and were on antipsychotic medication. Also there were an additional 2.5% met all the criteria, for example, they had the hallucinations, and suffered severe impairments but were not registered as schizophrenic patients. Schizophrenia is a mental disorder that affects about 1 in 100 people.

It also can appear at different stages of life and granted it can sometimes be difficult to diagnose. Sometimes the symptoms appear as on-set symptoms as early as age 7 but the actual severe symptoms begin typically around the ages of 18 to 30. Signs of Schizophrenia can be misread and sometimes overlooked because of all the other disorders that have many of the same symptoms. However, the opinion of this researcher is that if a professional researcher suspect a participant in a study to have any type of undiagnosed illness or disorder of any kind then it should be a practice of good ethics to get the participant the proper diagnosis and any help that is needed. Recurrent Depression

This section of the study was evaluated at the ages of 18, 21, 26, and 32 using what the researchers referred to as the “Diagnostic Interview Schedule” which is just an interview schedule used as the foundation of a structured interview that will provide the basis for a psychological assessment or psychiatric evaluation. According to Shaffer, Fisher, Lucas, Dulcan, Schwab-Stone, (2000) the “National Institute of Mental Health Diagnostic Interview Schedule for Children Version IV (NIMH DISC-IV) and how it differs from earlier versions of the interview. The NIMH DISC-IV is a highly structured diagnostic interview, designed to assess more than 30 psychiatric disorders occurring in children and adolescents, and can be administered by “lay” interviewers after a minimal training period”.

The researchers of this study Reichenberg, Caspi, Harrington, Houts, Keefe, Murray, & Moffitt (2010), only compared the the participants that had schizophrenia with the participants that had episodes of recurrent depression in an attempt to make a group that was more comparable to with the chronic course and severity of the illness of schizophrenia and 13.4% of the members did demonstrate symptoms of recurrent depression of two or more episodes. The actual statistical analysis was pretty simple there were 35 members of the cohort that were diagnosed as schizophrenic, 145 members were diagnosed with recurrent depression, there were 556 members that were healthy and had no other disorders, for example, anxiety or substance abuse issues. Results

These participants where all from the Dunedin Multidisciplinary Health and Development Study, which turns out to be a research unit known as the Dunedin Multidisciplinary Health and Development Unit or (DMHDRU), this unit has been doing the study for over 40 years, the Dunedin Study has several sub studies which include; Family Health History Study, and the on-going Parenting Study and Next Generation Study (DMHDRU, 2012). Actually these children were chosen from birth to participate in this study from the Queen Mary Maternity Hospital in Dunedin, New Zealand. These children’s first assessment began at age 3 and continue periodically throughout their lives, they return to the hospital for one day no matter where they live in the world. During the assessment almost all aspects of their health is assessed both physically and mentally. As the children reach a certain age they begin going through the sub studies, this is going to make quite an interesting paper. This connects to the week one assignment by being a clinical study and a type of depression and schizophrenia.

The children who developed the schizophrenia as adults displayed slow development in static cognitive impairments that began early in life and remained stable. These impairments were in both visual and verbal knowledge achievement, the interpretation of thought process and the forming of concepts. These children also showed signs of slower than normal comprehension on attention, information processing speed, the ability to solve problems, and memory. However no participant that had been diagnosed with a recurrent depression episode later in their life showed any of these intellectual patterns (Reichenberg, Caspi, Harrington, Houts, Keefe, Murray, & Moffitt, 2010).

The average child IQ was 94 of the members that developed schizophrenia, 98 for the members that were diagnosed with recurrent depression and 101 for the members that were healthy. The issue with this is that Rich (2011) reports that the IQ’s of all members of the cohort fall within the same range which is between “Low Average” (85) and “Average” (100). The interesting thing here is that there is an IQ Score Interpretation Calculator. If the numbers are entered there is really not that much change. The following are the categories that are measured using this calculator: Remember the IQ was measured at the ages of 7, 9, 12, 13, Age 7 IQ 94 (Schizophrenic)

What is interesting here is that the only time you really see a change at all is in the mental age category and also at the age of 13 the child for the first time as a mental age above the actual age. Now if the researchers would have continued to assess these children at the age of 16, then there are changes the mental ages are closer in points and in the healthy category the mental age is an adult. What this tells this researcher is that with an IQ of 94 and 98 a 16 year old person is closer in mental age to their actual age and at 101 they begin to think like an adult. So is there really that much that the IQ scores actually tell us without all factors that should have been taken under consideration for a healthy development of a child? Discussion

Efficacy, well I am not so sure that it can even be considered, yes the researchers found lags in both cognitive deficits and cognitive development during childhood. However not all factors were taken into consideration. Cognitive impairments can be caused by several different things, these conditions can occur at any time from before delivery to late in life. Some of the causes at the time of delivery are infection, lack of oxygen during delivery or preterm birth and any complications (localhealth.com, 2011). Some of the conditions that could cause these lags in childhood and adolescents are autism, head injury, heavy metal poisoning, some types of infection, kidney disease, malnutrition, among others (localhealth.com, 2011).

Some of the factors that were not mentioned in the study in regards to cognitive developmental lags can be peer rejection, environment, relationships with parents, stressors and other childhood trauma and also several others factors could come into play here. Although, medicalnewstoday.com (2010) discusses several types of schizophrenia, the type that was in the Dunedin Study would be childhood schizophrenia which also known as childhood-onset schizophrenia or early-onset schizophrenia. In the Dunedin Study the researchers found that the onset of the illness in children ages 7-13. Medicalnewstoday.com (2010), reports that in most cases the onset of schizophrenia begins at the age of 10. It is also reported that the illness is uncommon in children and also very tough to recognize in the onset phases. There needs to be better awareness of the symptoms and effects of depression and better ways to make sure that people get the help needed to overcome this illness. There are problems that need to face and barriers to overcome.

There are issues with the people seeking the help needed from professionals because they may think that there is just having a bad week or month or even year and that it will just go away on by itself. There also might be fears of becoming dependent on medications. People must realize that they need to seek not only medical treatment but also therapy to learn the skills needed to deal with the problems that cause the depression in the first place. It sounds as if there are signs that could lead to possibly being able to diagnose schizophrenia at an earlier age or at least know that the possibility is there for the development of the problem. However, there are probably several other reasons that can be at fault for children struggling with in school with issues like verbal reasoning for example, being able to listen to and recall spoken information (memory), or understand the meaning of written or spoken information, these children also seem to have issues with attention, and processing speed as they become older.

If schizophrenia is associated with lower childhood IQ in things like comprehension, attention, information processing speed, problem solving ability, and memory could there be a possibility that these symptoms could possibly be an indication of some other childhood trauma, for example, poor nutrition, family problems, abuse or even that the child comes from a low income family. Another example, if anxiety and/or stress are connected with why some people develop schizophrenia and anxiety and/or stress are also reasons why some children perform poorly in school, then it would not seem right to even suggest that these problems support the “neurodevelopmental model” of schizophrenia. According to the Psychology Encyclopedia (2012) schizophrenia is more common among the disadvantaged and affects more people that are in some of the lowest socioeconomic groups. It has also been proven that children that come from low-income families also tend to do more poorly in school. According to Strauss, (2010) 83% of children from low income families are not competent readers and are well below average in reading proficiently by fourth grade and that it has been known for a long time that poverty affects a child’s performance in school. The next big question is, is it symptoms of schizophrenia, poverty, abuse, or even neglect? Could it even be an environmental issue?


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