Curvilinear dependency of response accuracy on response time in cognitive tests

Abstract

The relationship between response time and accuracy in cognitive tasks is an important topic in experimental cognitive psychology as well as in the domain of cognitive testing, but the relationship is much more difficult to capture for the latter. Using data involving five cognitive tests: three academic achievement tests (knowledge tests) and two reasoning tests (perceptual and quantitative reasoning), the relationship between response time and response accuracy is explored after controlling for possible confounds associated with individual and item differences. The tests are different in terms of contents and type of test (achievement or ability test), but it was nonetheless found for all tests that response accuracy shows the same kind of curvilinear dependency on response time. Accuracy rates first increase rather rapidly and then decrease more slowly as a function of response time. The turning point came earlier for the three knowledge tests than for the two ability tests. The results are not easily reconcilable with simple principles that may apply to tasks used in cognitive experimental psychology. Possible explanations refer to discontinuities in the cognitive processes such as switching strategies, or a decline of cognitive efficiency and increasing cognitive depletion with passing time while working on problems that take much more time than the common tasks in experimental psychology.