Neurocognitive Tests on the iPad

1. Neurocognitive Tests on the iPad Sarah Waring1, Emily Whitaker1, James Blair2 1Department of Biomedical Engineering, 2Department of Anesthesiology, Vanderbilt University METHODS GOAL RESULTS Our goal was to create an iPad program that will be used to administer a battery of neurocognitive tests (primarily the Stroop test) as part of the pre-operative screening process. • Our Xcode programming and thorough troubleshooting resulted in a working Stroop test program that runs on the iPad. • Features include: • A start-up screen where the physician can enter a patient ID number that will be stored with the scores. • Patient instructions and “Start” button. • 32 quiz questions that progress from easy (word matches ink color) to more challenging (word and ink color do not match). Each question is timed for 5 seconds; if the patient cannot answer in time, he/she misses the question. • A results page where the physician can view the score report and/or export the scores (along with the patient ID number) through email. • Our test was found to be simple and easy to use when tested on university students. • We have created a program to be used with an iPad for administration because the device: • Is portable and lightweight • Has a long battery life • Has a touch screen, which is easy to use • Exhibits instant start-up • The iPad program will provide an easier and more efficient method to administer and score neurocognitive tests. • To create the program, we used Xcode and SDK, which program in Objective-C language. • Coding involved taking the idea of a simple “quiz” game and modifying for our purposes. • To code the Stroop test, we used current paper- and computer-based tests as resources. • Questions were chosen from a written Stroop test example and answer choices were selected using a random number generator. • The Stroop test program has the ability to enter a patient ID number and store and export scores. • The test requires that the user identify the color of the ink of a word when presented with a color word prompt. • Scoring is determined from response time and accuracy, both of which can be calculated in the iPad program. BACKGROUND • Post-operative cognitive dysfunction (POCD) is defined as the impairment of vital mental processes after surgery with anesthesia, and is most common in elderly patients. • To date, most “comprehensive” pre-operative screening neglects the brain. • Assessments of cognitive dysfunction are only performed after surgery, so there is no pre-op baseline to compare to. • Thus, a pre-operative test of mental function is needed. • In conjunction with Dr. James Blair, we are attempting to create a battery of neurocognitive tests to parallel his imaging studies using MRI/DTI/fMRI to determine if these tests can be a screening tool for risk of POCD. CONCLUSION and FUTURE DIRECTIONS Figure 3. Screenshot of the Stroop test start screen. The physician can enter a patient ID number to be stored along with the scores. Figure 4. Screenshot of an example Stroop test question on the iPad. The user must identify the color of the ink, which in this case matches the word. Figure 5. Another screenshot of an example question; this time, the color of the ink does not match the word, making it more challenging. Figure 6. Screenshot of the results page of the Strooptest. The physician can view the scores and also export to email for easy data storage. • The final iPad program will be used in conjunction with physiological imaging (performed by Dr. Blair) to detect changes in cognitive function and brain structures, and will provide easier methods of test administration to facilitate his study. • The creation of a successful program will allow for the combination of multiple tests and easy data transfer for analysis, thus cutting costs. • We hope our program will help continue research into POCD and help researchers gain more knowledge of how surgery and anesthesia affect the brain. • In the future, we hope this study will ultimately lead to a development of better anesthetic practices to decrease cases of POCD in the elderly. • Finally, the program could eventually appear in Apple’s App Store (after getting approval) for distribution so that other hospitals can use it for screening. Figure 1. The anterior cingulate cortex (ACC) is thought to be the area of the brain that functions while taking the Stroop test. Figure 2.Example of the paper version of the Stroop test. Lines 1-2: font color matches the word; lines 3-8: font color does not match the word. REFERENCES • The Stroop Test is a neurocognitive test that assesses concept shifting ability and executive function. • The test presents the patient with a series of color words that appear in different colored inks. • The patient’s score is based on both timing and accuracy in selecting the correct ink color. • Traditionally administered on paper by a trained proctor, the Stroop test has recently been modified for the computer. • Hanning, C.D. “Postoperative cognitive dysfunction.” British Journal of Anaesthesia 95(1): 82-87. • Monk, T.G., et al. “Predictors of cognitive dysfunction after major noncardiac surgery.” Anesthesiology 108(1):18-30. • Monk, T.G., et al. “Anesthetic management and one-year mortality after noncardiac surgery.” AnesthAnalg 100(1):4-10. • Ancelin, M. et al. "Exposure to Anesthetic Agents, Cognitive Functioning and Depressive Symptomology in the Elderly." British Journal of Psychiatry 178(2001): 360-66. • Pardo, J.V., et al. “The anterior cingulate cortex mediates processing selection in the Stroopattentional conflict paradigm.” Proc. Natl. Acad. Sci. USA 87(1990):256-259.