[Formula: see text]Official Position of the American Academy of Clinical Neuropsychology (AACN): Guidelines for Practicum Training in Clinical Neuropsychology.

Practical experience is central to the education and training of neuropsychologists, beginning in graduate school and extending through postdoctoral fellowship. However, historically, little attention has been given to the structure and requirements of practicum training in clinical neuropsychology. A working group of senior-level neuropsychologists, as well as a current postdoctoral fellow, all from a diverse range of settings (The AACN Practicum Guidelines Workgroup), was formed to propose guidelines for practicum training in clinical neuropsychology. The Workgroup reviewed relevant literature and sought input from professional organizations involved in education and training in neuropsychology. The proposed guidelines provide a definition of practicum training in clinical neuropsychology, detail entry and exit criteria across competencies relevant to practicum training in clinical neuropsychology, and discuss the relationship between doctoral training programs and practicum training sites. The proposed guidelines also provide a methodology for competency-based evaluation of clinical neuropsychology practicum trainees and outline characteristics and features that are integral to an effective training environment. Although the guidelines discussed below may not be implemented in their entirety across all clinical neuropsychology practicum training sites, they are consistent with the latest developments in competency-based education.

The role of sleep in forgetting in temporal lobe epilepsy: a pilot study.

The purpose of this study was to examine how sleep impacts memory function in temporal lobe epilepsy (TLE). Patients with TLE (n=7) and control subjects (n=9) underwent training and overnight testing on (1) a motor sequence task known to undergo sleep-dependent enhancement in healthy subjects, and (2) the selective reminding test, a verbal memory task on which patients with TLE have shown impaired performance 24 hours after training. Sleep data were collected by polysomnography. Results indicate that patients with TLE display greater forgetting on the selective reminding test compared with controls over 12 hours of daytime wakefulness, but not over a similar period including a night of sleep. Slow wave sleep is correlated with overnight performance change on the selective reminding test. Patients with TLE show no deficit in sleep-dependent motor sequence task improvement. The findings provide potential insight into the pattern and pathophysiology of forgetting in TLE.

Threshold-independent functional MRI determination of language dominance: a validation study against clinical gold standards.

Functional MRI (fMRI) is often used for presurgical language lateralization. In the most common approach, a laterality index (LI) is calculated on the basis of suprathreshold voxels. However, strong dependencies between LI and threshold can diminish the effectiveness of this technique; in this study we investigated an original methodology that is independent of threshold. We compared this threshold-independent method against the common threshold-dependent method in 14 patients with epilepsy who underwent Wada testing. In addition, clinical results from electrocortical language mapping and postoperative language findings were used to assess the validity of the fMRI lateralization method. The threshold-dependent methodology yielded ambiguous or incongruent lateralization outcomes in 4 of 14 patients in the inferior frontal gyrus (IFG) and in 6 of 14 patients in the supramarginal gyrus (SMG). Conversely, the threshold-independent method yielded unambiguous lateralization in all the patients tested, and demonstrated lateralization outcomes incongruent with clinical standards in 2 of 14 patients in IFG and in 1 of 14 patients in SMG. This validation study demonstrates that the threshold-dependent LI calculation is prone to significant within-patient variability that could render results unreliable; the threshold-independent method can generate distinct LIs that are more concordant with gold standard clinical findings.

Mild cognitive impairment: a neuropsychological perspective.

Mild cognitive impairment (MCI) is a clinical diagnosis in which deficits in cognitive function are evident but not of sufficient severity to warrant a diagnosis of dementia. For the majority of patients, MCI represents a transitional state between normal aging and mild dementia, usually Alzheimer's disease. Multiple subtypes of MCI are now recognized. In addition to presentations featuring memory impairment, symptoms in other cognitive domains (eg, executive function, language, visuospatial) have been identified. Neuropsychological testing can be extremely useful in making the MCI diagnosis and tracking the evolution of cognitive symptoms over time. A comprehensive test battery includes measures of baseline intellectual ability, attention, executive function, memory, language, visuospatial skills, and mood. Informant-based measures of neuropsychiatric symptoms, behaviors, and competency in instrumental activity are also included. Careful assessment can identify subtle deficits that may otherwise elude detection, particularly in individuals of superior baseline intellectual ability. As we move closer to disease-modifying therapy for Alzheimer's disease, early identification becomes critical for identifying patients who have an opportunity to benefit from treatment.

Functional MRI of memory in the hippocampus: Laterality indices may be more meaningful if calculated from whole voxel distributions.

Lateralization of memory by functional MRI (fMRI) may be helpful for surgical planning related to the medial temporal lobe (MTL). Most fMRI memory studies have calculated lateralization indices (LI) in the MTL from suprathreshold voxels only, but the selection of threshold remains highly arbitrary. We hypothesized that LIs could be reliably extracted from the distribution of voxels encompassing all positive T statistical values, each weighted by their own statistical significance. We also hypothesized that patient LIs that are two or more standard deviations (SD) away from the control group mean LI may be more clinically relevant than LIs that are not compared to control group. Thirteen healthy subjects had memory fMRI, and five epilepsy patients had both fMRI and the intracarotid amobarbital procedure (IAP). The fMRI task consisted of encoding patterns, scenes, and words. We found that normal subjects' LIs extracted from whole weighted statistical distributions tended to lateralize to the left for words, to the right for patterns, and intermediately for scenes, consistent with previous research. Weighted LIs were less variable than those calculated from suprathreshold voxels only. Using this approach, all patients had fMRI memory lateralizations consistent with IAP results. The weighted LIs provided a more clear-cut distinction of patients from the normal group (in terms of SDs from the group mean) than the suprathreshold voxel count approach. Our results suggest that using weighted distributions can be a useful strategy for assessing memory lateralization by fMRI in the MTL.