Functional MRI is increasingly recognized for its potential as a powerful new tool in clinical neuropsychology. This is likely due to the fact that, with some degree of innovation, it is possible to convert practically any familiar cognitive test into one that can be performed in the MRI scanning environment. However, like any assessment approach, meaningful interpretation of fMRI data for the purpose of patient evaluation crucially requires normative data derived from a sample of unimpaired persons, against which individual patients may be compared. Currently, no such normative data are available for any fMRI-based cognitive testing protocol. In this paper, we report the first of a series of fMRI-compatible cognitive assessment protocols, a matrix reasoning test (f-MRT), for which normative samples of functional activation have been collected from unimpaired control subjects and structured in a manner that makes individual patient evaluation possible in terms of familiar z-score distributions. Practical application of the f-MRT is demonstrated via a contrastive case-study of two individuals with cognitive impairment in which fMRI data identifies subtleties in patient deficits otherwise missed by conventional measures of performance.

In this study, we describe an fMRI version of the verbal fluency test. This is the second in a series of fMRI adaptations of classical neuropsychological tests, for which normative samples of functional activation have been collected from unimpaired control subjects and structured in a manner that makes individual patient evaluation possible in terms of familiar z-score distributions. This fMRI protocol is shown to have strong convergent validity with the FAS phonemic fluency test and to elicit activation patterns highly consistent with a large body of previous neuroimaging studies of verbal fluency. We also present a case study, in which we report concurrent data from a patient with selective deficits in verbal processing, using both conventional neuropsychological and fMRI approaches. These analyses reveal striking correspondences between the deficits present in this patient on cognitive performance tests and the equally selective patterns of deviation present in his fMRI data.

Recent progress has been made using fMRI as a clinical assessment tool, often employing analogues of traditional “paper and pencil” tests. The Trail Making Test (TMT), popular for years as a neuropsychological exam, has been largely ignored in the realm of neuroimaging, most likely because its physical format and administration does not lend itself to straightforward adaptation as an fMRI paradigm. Likewise, there is relatively more ambiguity about the neural systems associated with this test than many other tests of comparable clinical use. In this study, we describe an fMRI version of Trail Making Test-B (TMTB) that maintains the core functionality of the TMT while optimizing its use for both research and clinical settings. Subjects (N = 32) were administered the Functional Trail Making Test-B (f-TMTB). Brain region activations elicited by the f-TMTB were consistent with expectations given by prior TMT neurophysiological studies, including significant activations in the ventral and dorsal visual pathways and the medial pre-supplementary motor area. The f-TMTB was further evaluated for concurrent validity with the traditional TMTB using an additional sample of control subjects (N = 100). Together, these results support the f-TMTB as a viable neuroimaging adaptation of the TMT that is optimized to evoke maximally robust fMRI activation with minimal time and equipment requirements.

Background:Emerging research proposes the imbalance between microvascular supply and metabolic demand as a contributing factor in the pathophysiology of mild traumatic brain injury. Prolonged effects on the dysregulation of neurovascular coupling may explain persistent symptomatic models such as Post-Concussion Syndrome.Objective:Increased knowledge of what we refer to as neurovascular uncoupling provides a template for establishing a new concussion treatment standard in the assessment and therapeutic guidance of concussion.Methods:The degree and localization of neurovascular uncoupling were statistically contextualized against a normative-based atlas in 270 concussed patients. Functional NeuroCognitive ImagingTM was used to establish pre-treatment benchmarks and guide neurotherapy. Conventional and functional neurocognitive imaging-directed measures were used to evaluate post-rehabilitative outcomes.Results:Functional neurocognitive imaging was successful in identifying regions of Neurovascular uncoupling unique to each patient’s brain and concussion profile. Longitudinal objective outcome measures demonstrated timely and lasting improvement of neurovascular coupling functioning in a significant majority of patients.Conclusion:We present practice-based evidence supporting the clinical administration of functional neurocognitive imaging with particular efficacy in the neurorehabilitation of concussion. We advocate the reliability of functional neurocognitive imaging in assessing severity and localization of neurovascular uncoupling, and promote its use in the therapeutic guidance and neurorehabilitation of mild traumatic brain injury. We further support the continual exploration of other potential pathophysiological alterations resulting from concussion.

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