Schizophrenia is a largely misunderstood mental illness. For many people, their only experience with this disease is what they see in films. Schizophrenics are often portrayed as violent individuals that abuse drugs and/or alcohol, and had troubled childhoods. The reality is that, in general, these things don’t apply. Individuals with schizophrenia suffer from a long list of cognitive, psychotic, and emotional problems caused by deficits in the brain. Although schizophrenia has been researched for over 100 years there is still a lot that experts don’t understand about the disease. A recent study led by the University of Nottingham in the United Kingdom argues that we are looking at schizophrenia all wrong. Results from the study suggest that schizophrenia may be an extreme personality that exists on a spectrum with healthy personality types.
A previous study found that compared to healthy controls individuals with schizophrenia exhibit a weakened response in the brain to motor visuomotor tasks. The researchers of the Nottingham study wanted to know if this also applied to individuals with schizotypal personality traits. Schizotypy (SPD) is a personality disorder characterized by brief psychotic episodes. Traits of this disorder lie on a spectrum and affect normal healthy individuals to people with full blown SPD. The study was conducted at the University of Nottingham and Cardiff University in Wales. The researchers recruited a total of 166 healthy volunteers from imaging centers on their campuses. The volunteers each filled out a Schizotypal Personality Questionnaire (SPQ) which is a self-reported survey that measures normal to abnormal degrees of schizotypy. Researchers then used Magnetoencephalography (MEG), a technique that measures the magnetic fields generated by neuronal activity of the brain, to look at brainwaves while participants moved their index finger. Correlations between MEG and SPQ results were then computed. The study found a significant negative correlation between the two, suggesting that schizophrenia is on a continuum with schizotypy and is an extreme form with more severe neural deficits.
This study seems very well thought out and the methods were very thorough. The researchers complied to a strict criteria for exclusion of volunteers. The volunteers consisted of both male and females and while there were more females the researchers conducted statistical analysis and determined that the difference was not significant. This was then done to control for sex of the participants. The choice to use MEG to measure brain function seems like a good choice. MEG can measure brain activity extremely fast, unlike EEG it can localize brainwaves, and unlike fMRI it measures direct brain function. The researchers also used a sampling with replacement technique in their data analysis which allowed them to check the reliability of their results.
Even though this study is methodically strong I question the small sample size and issues surrounding the SPQ. Sample size can influence the power of a study to detect the size of an effect. With a small sample size there is an increased risk for a Type II error in which results confirm the hypothesis when in fact the alternative is true. Due to this I would expect to see this study repeated to strengthen the conclusions. I have multiple concerns with the SPQ. While self-reported surveys can help to measure constructs of personality that would otherwise be difficult to measure they come with a multitude of problems. Not only do they rely on the honesty of participants, but not all participants are going to understand or interpret the questions the same. Another concern I have with with the SPQ is how it was conducted. At one site the survey was conducted in-person under the supervision of an experimenter and at the other participants filled it out online before meeting with experimenters. People often behave differently when being watched so could this difference have effected answers? My last concern is the differences in the scales used for the SPQ at the two sites. One site used a 5-point Likert scale while the other used a binary scale. The article does state that participant total scores were normalized using standard deviations and means, however I still wonder how the differences in scale could have influenced how participants answered the survey questions.
Overall I’d say this a fairly strong study, however before I jump on the band wagon I’d like to see this study repeated with more uniform questionnaire practices and a larger sample size. With that said the researchers bring to light a very thought provoking topic on how we view schizophrenia and mental illness as a whole in our society. I think this study does a good job of humanizing people with schizophrenia and showing that they exists on a spectrum of human experience with everyone else and not on another plane entirely. This can go far way in helping to destigmatize mental illness and change the way schizophrenia is portrayed in Hollywood.
Refernces
Liddle, et al. “Attenuated Post-Movement Beta Rebound Associated With Schizotypal Features in Healthy People.” OUP Academic, Oxford University Press, 18 Sept. 2018, academic.oup.com/schizophreniabulletin/advance-article/doi/10.1093/schbul/sby117/5095481.
Data/Society/Decision-making Spring 2019 