Diverse experiences and approaches to tele neuropsychology: Commentary and reflections over the past year of COVID-19
Neuropsychological assessment of adults being considered for mechanical circulatory support
Cham, Switzerland: Springer Nature Switzerland AG; Switzerland, 2019
New York : Oxford University Press, 2019
Assessment Trends Among Neuropsychologists Conducting Sport-Related Concussion Evaluations
Neuropsychologists regularly conduct sport-related concussion (SRC) evaluations, although research has not tracked these assessment practices. As part of a survey of neuropsychological test usage, we analyzed data from 215 neuropsychologists who conduct SRC evaluations. Only 15% reported conducting baseline assessments of athletes as part of a sports program and 92% evaluate athletes' post-concussion without baseline data. The majority of respondents use a full battery, considered the most reliable approach for assessing concussion symptoms in athletes. Only 6% use computerized tests exclusively (>50% ImPACT). We discuss the implications of these results and address challenges faced by neuropsychologists who perform SRC evaluations.
Management of Cognitive Impairment in Heart Failure
OPINION STATEMENT/UNASSIGNED:Cognitive impairment (CI) is an inclusive term to describe trouble with memory, learning, concentration, or decision-making. CI is highly prevalent in patients with heart failure (HF) and is known to be associated with a variety of poor outcomes. While published HF guidelines recommend screening for CI, they do not indicate how, due to a lack of consensus in the literature about which instrument to use. Our recommendation is to use the Mini-Cog for this purpose because of its brevity and utility in identifying patients with HF at high risk for hospitalization or mortality. At this time, there is minimal published clinical trial evidence about how to manage CI in patients with HF. Reasonable approaches to management may include following guideline-directed medical therapy for HF, treatment of hypertension and atrial fibrillation, management of depression, proactive diagnosis and treatment of sleep apnea, and encouragement of aerobic exercise and weight loss. Left ventricular assist device (LVAD) therapy in patients with Stage D HF may improve CI in the short term after implantation, though there is a risk of worsening CI in the intermediate and long term. Clinicians who care for patients with HF should routinely screen for CI and when identified should encourage interventions to support self-care, increase family involvement, and arrange for more frequent follow-up.
Dominance of orientation over frequency in the perception of 3-D slant and shape
In images of textured three-dimensional surfaces, pattern changes can be characterized as changes in orientation and spatial frequency, features for which neurons in primary visual cortex are classically selective. Previously, we have demonstrated that correct 3-D shape perception is contingent on the visibility of orientation flows that run parallel to the surface curvature. We sought to determine the relative contributions of orientation modulations (OMs) and frequency modulations (FMs) for the detection of slant and shape from 3-D surfaces. Results show that 1) when OM and FM indicate inconsistent degrees of surface slant or curvature, observer responses were consistent with the slant or curvature specified by OM even if the FM indicated a slant or curvature in the opposite direction to the same degree. 2) For slanted surfaces, OM information dictates slant perception at both shallow and steep slants while FM information is effective only for steep slants. Together these results point to a dominant role of OM information in the perception of 3-D slant and shape.
Sensory deprivation differentially impacts the dendritic development of pyramidal versus non-pyramidal neurons in layer 6 of mouse barrel cortex
Early postnatal sensory experience can have profound impacts on the structure and function of cortical circuits affecting behavior. Using the mouse whisker-to-barrel system we chronically deprived animals of normal sensory experience by bilaterally trimming their whiskers every other day from birth for the first postnatal month. Brain tissue was then processed for Golgi staining and neurons in layer 6 of barrel cortex were reconstructed in three dimensions. Dendritic and somatic parameters were compared between sensory-deprived and normal sensory experience groups. Results demonstrated that layer 6 non-pyramidal neurons in the chronically deprived group showed an expansion of their dendritic arbors. The pyramidal cells responded to sensory deprivation with increased somatic size and basilar dendritic arborization but overall decreased apical dendritic parameters. In sum, sensory deprivation impacted on the neuronal architecture of pyramidal and non-pyramidal neurons in layer 6, which may provide a substrate for observed physiological and behavioral changes resulting from whisker trimming.
Physiology and morphology of callosal projection neurons in mouse
In the mammalian neocortex, the corpus callosum serves as the major source of interhemispheric communication, composed of axons from callosal neurons located in supragranular (II/III) and infragranular (V/VI) layers. We sought to characterize the physiology and morphology of supragranular and infragranular callosal neurons in mice using retrograde tracers and whole-cell patch clamp recordings. Whole-cell patch clamp recordings were made from retrogradely labeled callosal neurons following unilateral injection of fluorescent latex microspheres in the contralateral sensory-motor cortex. Following recordings and biocytin dialysis, labeled neurons were reconstructed using computer-assisted camera lucida (Neurolucida) for morphological analyses. Whole-cell recordings revealed that callosal neurons in both supra- and infragranular layers display very similar intrinsic membrane properties and are characteristic regular-spiking neurons. Morphological features examined from biocytin-filled reconstructions as well as retrogradely BDA labeled cells did not reveal any differences. Analysis of spontaneous postsynaptic potentials from callosal neurons did reveal several differences including average amplitude, frequency, and decay time. These findings suggest that callosal neurons in both supra- and infragranular layers have similar phenotypes though belong to different local, intracortical networks.