The overall goal of the following experiment is to examine handwriting in individuals at risk for psychosis. This is achieved by recruiting two groups of participants. The first group is made up of healthy controls, and the second group is made up of individuals at risk for psychosis.
As a second step, participants use a pen enabled tablet computer to provide handwriting data, which is analyzed by software. Next, statistical analysis compares the ultra high risk participants to healthy controls on a measure of pen movement, disfluency called average normalized jerk results are obtained that show individuals at risk for psychosis show greater pen movement disfluency a proximal measure for spontaneous dyskinesia based on significantly larger values of average normalized jerk. The main advantages of this technique over existing methods, such as instrumental strain gauges, or observer based reports, is that it makes it easier for us to train raiders and reduces experimental bias.
In addition, we are able to compare trials across multiple sites, which is something we haven't been able to do until now. Demonstrating this procedure is Derek Dean, a graduate student from my laboratory, Tina Gupta. Our clinical coordinator will enact the role of a participant.
The first task is to find study participants through email, internet, and traditional ads. Recruit adolescent and young adult subjects with an ultra high risk for development of psychosis and healthy control. Subjects exclude all participants based on a history of head injury, neurological disorder, substance dependence, or a history of taking neuroleptic medication of the initial participants.
Exclude healthy controls based on the presence of any category of Axis one disorder or a psychotic disorder in a first degree relative, exclude ultra high risk participants based on the presence of an Axis one psychotic disorder. For each continuing participant, use the structured interview for prodromal syndromes to diagnose prodromal syndrome. Then use the structured clinical interview for Axis one DSM four disorders to rule out a psychotic disorder diagnosis.
Also assess nicotine use for the month prior to testing on a zero to four scale for later comparison. Note that the ultra high risk participants included in this study rate significantly higher than controls on all symptom domains in the structured interview. For prodromal syndrome, the handwriting task is conducted in an assessment room seat the participant across the table from the investigator's chair.
Have a note card prepared with an example in script of L-L-E-E-L-L-E-E. Place the card so it'll be visible to the participant throughout the experiment. Next on a pen enabled tablet, computer.
Start running neuros script. Move software. Orient the tablet into landscape mode.
To provide the necessary writing space, allow the participant to position the computer screen in a comfortable writing position. Proceed by explaining the instructions displayed at the top of the screen to the participant. Use your dominant hand to write the sample.
Write in cursive, stay within the two centimeter guidelines. Work at a comfortable speed. These instructions will be visible during each trial.
Instruct the participant to begin the handwriting. Task is complete. When the participant has provided three samples, the writing samples have already been processed by the handwriting analysis software.
Select the appropriate settings for determining the average normalized jerk. Proceed with the analysis. The 16 strokes analyzed for average normalized jerk are shown here.
They alternate between blue as in this segment and red in color. The beginning and end of each segment is indicated by a circle. This trial is from a control participant.
Compare this with the Disfluent pen movement of a member of the ultra high risk group. Analysis of Covance reveals the control in ultra high risk groups have a significant difference. In average, normalized jerk indicating more disfluent pen movements among the ultra high risk group.
This suggests the handwriting analysis may have detected the presence of dyskinesia in the high risk participants. When you attempt this procedure, it is important to give the participant clear directions. Once mastered, this technique can be completed in 10 minutes After its development.
This technique paved the way for advances in the field of clinical science. We're able to examine movement abnormalities and underlying neurological dysfunction and youth who are at risk for developing serious mental illnesses and psychotic disorders such as schizophrenia.
