Sync-Think™

Reaction times are very often used to measure a person's alertness or level of attention. Research at the Brain Trauma Foundation (BTF) and many other research institutions have found that the variability of reaction times rather than the actual reaction time is a better indicator of attention.

Individuals with fatigue, aging, attention deficit disorder (ADD) and traumatic brain injury (TBI) have problems maintaining attention, and they show more variability on reaction time tests than the normal population.* This variability can be a result of degeneration or damage to brain attention circuits in aging and TBI respectively, a transient decrease in function such as in fatigue or a developmental problem such as in ADD.

BTF has a collaborative research project with experts from Cornell, UC Berkeley and UCSF, with a grant from the James S. McDonnell Foundation, to study the biology of attention deficits in mild TBI and see if there are links with subtle brain shear injury and timing problems. Research studies from the consortium show subtle shear injury correlating with attention and memory difficulties following mild TBI.**

However, attention can change second to second and reaction time tests may miss fluctuations in variability. BTF has developed and published a unique eye tracking variability analysis to monitor moment-to-moment attention. This system will be used to quickly evaluate attention in sports concussion, mild TBI and even to detect fatigue.

The two tests on this site are an introduction to the field of reaction times and variability. At the present time the resolution of computer-internet eye tracking systems are not sufficient to do quality variability analyses, so tapping to a beat is used in test number 2 to measure variability. We use three different beat rhythms to examine variability in different time frames. Test number 1 is a simple reaction test.

These tests are provided for your education and enjoyment and are not intended to be clinically diagnostic. The rankings of reaction times and variability are completely arbitrary and based on the population of people taking the tests. You will not be asked for any identifiers and we do not screen users. You must take test 1 and test 2 to get test results. Total time for both tests is approx. 3 minutes.

Test 1 description: 10 reaction time tests - each 1 to 3 seconds long, total time = approx. 30 seconds

Test 2 description:  3 variability tapping to beat tests preceded by short exercise trials - each 30 to 40 seconds long, total time = approx. 2 minutes

*     Fuentes K, Hunter MA, Strauss E, Hultsch DF. Intraindividual variability in cognitive performance in persons with chronic fatigue syndrome. Clin Neuropsychol. 2001;15:210-227.

Hultsch DF, MacDonald SW, Dixon RA. Variability in reaction time performance of younger and older adults. J Gerontol B Psychol Sci Soc Sci. 2002;57:101-115.

Stuss DT, Pogue J, Buckle L, Bondar J. Characterization of stability of performance in patients with traumatic brain injury: variability and consistency on reaction time test. Neuropsychology. 1994;8:316-324.

Toplak ME, Tannock R. Tapping and anticipation performance in attention deficit hyperactivity disorder. Percept Mot Skills. 2005;100:659-675.

 

**   Le TH, Mukherjee P, Henry RG, Berman JI, Ware M, Manley GT. Diffusion tensor imaging with three-dimensional fiber tractography of traumatic axonal shearing injury: an imaging correlate for the posterior callosal "disconnection" syndrome: case report. Neurosurgery. 2005;56:189.

Suh M, Basu S, Kolster R, Sarkar R, McCandliss B, Ghajar J. Increased oculomotor deficits during target blanking as an indicator of mild traumatic brain injury. Neurosci Lett. 2006;410:203-207.

Suh M, Kolster R, Sarkar R, McCandliss B, Ghajar J. Deficits in predictive smooth pursuit after mild traumatic brain injury. Neurosci Lett. 2006;401:108-113.