Verbal learning differences in chronic mild traumatic brain injury

Following mild traumatic brain injury (TBI), a percentage of individuals report chronic memory and attention difficulties. Traditional neuropsychological assessments often fail to find evidence for such complaints. We hypothesized that mild TBI patients may, in fact, experience subtle cognitive deficits that reflect diminished initial acquisition that can be explained by changes in cerebral white matter microstructure. In the data presented here, a sample of nonlitigating and gainfully employed mild TBI patients demonstrated statistically significant differences from age and education matched control participants in performance on the first trial of a verbal learning task. Performance on this trial was associated with reduced fractional anisotropy in the uncinate fasciculus and the superior longitudinal fasciculus providing an anatomical correlate for the cognitive findings. Mild TBI patients were not impaired relative to control participants on total learning or memory composite variables. Performance on the first learning trial was not related to any psychological variables including mood. We concluded that patients with mild TBI demonstrate diminished verbal learning that is not often interpreted in standard neuropsychological assessment. Copyright © The International Neuropsychological Society 2010

Verbal learning strategy following mild traumatic brain injury

That learning and memory deficits persist many years following mild traumatic brain injury (mTBI) is controversial due to inconsistent objective evidence supporting subjective complaints. Our prior work demonstrated significant reductions in performance on the initial trial of a verbal learning task and overall slower rate of learning in well-motivated mTBI participants relative to demographically matched controls. In our previous work, we speculated that differences in strategy use could explain the differences in rate of learning. The current study serves to test this hypothesis by examining strategy use on the California Verbal Learning Test-Second Edition. Our present findings support the primary hypothesis that mTBI participants under-utilize semantic clustering strategies during list-learning relative to control participants. Despite achieving comparable total learning scores, we posit that the persisting learning and memory difficulties reported by some mTBI patients may be related to reduced usage of efficient internally driven strategies that facilitate learning. Given that strategy training has demonstrated improvements in learning and memory in educational and occupational settings, we offer that these findings have translational value in offering an additional approach in remediation of learning and memory complaints reported by some following mTBI. © Copyright The International Neuropsychological Society 2011

Safety of human MRI at static fields above the FDA 8T guideline: Sodium imaging at 9.4T does not affect vital signs or cognitive ability.

Purpose: To assess whether exposure to a 9.4T static magnetic field during sodium imaging at 105.92 MHz affects human vital signs and cognitive function. Materials and Methods: Measurements of human vital signs and cognitive ability made before and after exposure to a 9.4T MR scanner and a mock scanner with no magnetic field are compared using a protocol approved by the United States Food and Drug Administration. Results: Exposure to a 9.4T static magnetic field during sodium imaging did not result in a statistically significant change in the vital signs or cognitive ability of healthy normal volunteers. Conclusion: Vital sign and cognitive ability measurements made before and after sodium imaging at 9.4T suggest that performing human MRI at 105.92 MHz in a 9.4T static magnetic field does not pose a health risk

Symptom validity assessment: Practice issues and medical necessity: NAN Policy & Planning Committee

Symptom exaggeration or fabrication occurs in a sizeable minority of neuropsychological examinees, with greater prevalence in forensic contexts. Adequate assessment of response validity is essential in order to maximize confidence in the results of neurocognitive and personality measures and in the diagnoses and recommendations that are based on the results. Symptom validity assessment may include specific tests, indices, and observations. The manner in which symptom validity is assessed may vary depending on context but must include a thorough examination of cultural factors. Assessment of response validity, as a component of a medically necessary evaluation, is medically necessary. When determined by the neuropsychologist to be necessary for the assessment of response validity, administration of specific symptom validity tests are also medically necessary. © 2005 Published by Elsevier Ltd on behalf of National Academy of Neuropsychology

The importance of neuropsychological assessment for the evaluation of childhood learning disorders NAN Policy and Planning Committee

When children experience learning difficulties, an appropriate evaluation of abilities and skills can provide the foundation for an accurate diagnosis and useful recommendations. When comprehensive information about a child\u27s brain-related strengths and weaknesses is necessary to understand potential sources of the problem and implications for functioning, a neuropsychological evaluation is most often the best choice. This paper was written to help parents, educators, health care providers, and third-party payors to understand the nature of neuropsychological assessment and to choose the type of evaluation that will furnish relevant information for the child\u27s educational planning

Independent and court-ordered forensic neuropsychological examinations: Official statement of the National Academy of Neuropsychology

Independent forensic neuropsychological examinations are performed by neuropsychologists who are hired as independent contractors by third parties to make determinations regarding neuropsychological functioning. The responsibilities of neuropsychologists when performing independent or court-ordered forensic examinations differ from those of clinical examinations. Because neuropsychological training typically occurs in clinical contexts, the transition to forensic contexts may result in uncertainty about how to negotiate the unique responsibilities of the forensic examiner role. Neuropsychologists are responsible for maintaining the highest standards of professional practice when performing independent and court-ordered forensic examinations. To reach and maintain the highest standards of practice, neuropsychologists must understand the unique relationships with retaining parties and examinees and strive to maintain true independence and objectivity. Although a true neuropsychologist-patient relationship is not considered to exist within the context of a forensic neuropsychological evaluation, neuropsychologists have ethical responsibilities to both the retaining party and the examinee. © 2005 National Academy of Neuropsychology. Published by Elsevier Ltd. All rights reserved