Commentary on Why Not Teach Critical Thinking by B. Hamby

Some ways of teaching critical thinking seem destine to failure, e.g.,CT across the curriculum, and some obstacles to acquiring CT skills seem insurmountable, e.g., cognitive biases, but some approaches to teaching and learning to think critically, discussed in this article, can mitigate those biases and be demonstrably successful

Commentary on “A Three-Dimensional Analysis of Definition with Bearing on Key Concepts” by Robert Ennis

On the nature of definitions and concepts, and the definition of critical thinking

Light bulb moments: identifying information research threshold concepts for fourth year engineering students

The librarians in the Dorothy Hill Physical Sciences and Engineering Library undertook a project to identify information research threshold concepts which fourth year undergraduate students must know to produce high quality research assignments. The methodology used to identify threshold concepts was to survey students, librarians and academics. A suggested threshold concept in information research is the critical evaluation of information resources to establish their authority, quality and credibility. This paper aims to demonstrate how a threshold concept approach clarifies the student experience in information research and provides a framework for the design of future information skills training

Dementia assessment and management in primary care settings: a survey of current provider practices in the United States.

BACKGROUND:Primary care providers (PCPs) are typically the first to screen and evaluate patients for neurocognitive disorders (NCDs), including mild cognitive impairment and dementia. However, data on PCP attitudes and evaluation and management practices are sparse. Our objective was to quantify perspectives and behaviors of PCPs and neurologists with respect to NCD evaluation and management. METHODS:A cross-sectional survey with 150 PCPs and 50 neurologists in the United States who evaluated more than 10 patients over age 55 per month. The 51-item survey assessed clinical practice characteristics, and confidence, perceived barriers, and typical practices when diagnosing and managing patients with NCDs. RESULTS:PCPs and neurologists reported similar confidence and approaches to general medical care and laboratory testing. Though over half of PCPs performed cognitive screening or referred patients for cognitive testing in over 50% of their patients, only 20% reported high confidence in interpreting results of cognitive tests. PCPs were more likely to order CT scans than MRIs, and only 14% of PCPs reported high confidence interpreting brain imaging findings, compared to 70% of specialists. Only 21% of PCPs were highly confident that they correctly recognized when a patient had an NCD, and only 13% were highly confident in making a specific NCD diagnosis (compared to 72 and 44% for neurologists, both p < 0.001). A quarter of all providers identified lack of familiarity with diagnostic criteria for NCD syndromes as a barrier to clinical practice. CONCLUSIONS:This study demonstrates how PCPs approach diagnosis and management of patients with NCDs, and identified areas for improvement in regards to cognitive testing and neuroimaging. This study also identified all providers' lack of familiarity with published diagnostic criteria for NCD syndromes. These findings may inform the development of new policies and interventions to help providers improve the efficacy of their decision processes and deliver better quality care to patients with NCDs

A comparison of magnetic resonance imaging and neuropsychological examination in the diagnostic distinction of Alzheimer’s disease and behavioral variant frontotemporal dementia

The clinical distinction between Alzheimer's disease (AD) and behavioral variant frontotemporal dementia (bvFTD) remains challenging and largely dependent on the experience of the clinician. This study investigates whether objective machine learning algorithms using supportive neuroimaging and neuropsychological clinical features can aid the distinction between both diseases. Retrospective neuroimaging and neuropsychological data of 166 participants (54 AD; 55 bvFTD; 57 healthy controls) was analyzed via a Naïve Bayes classification model. A subgroup of patients (n = 22) had pathologically-confirmed diagnoses. Results show that a combination of gray matter atrophy and neuropsychological features allowed a correct classification of 61.47% of cases at clinical presentation. More importantly, there was a clear dissociation between imaging and neuropsychological features, with the latter having the greater diagnostic accuracy (respectively 51.38 vs. 62.39%). These findings indicate that, at presentation, machine learning classification of bvFTD and AD is mostly based on cognitive and not imaging features. This clearly highlights the urgent need to develop better biomarkers for both diseases, but also emphasizes the value of machine learning in determining the predictive diagnostic features in neurodegeneration

Rule violation errors are associated with right lateral prefrontal cortex atrophy in neurodegenerative disease

Good cognitive performance requires adherence to rules specific to the task at hand. Patients with neurological disease often make rule violation errors, but the anatomical basis for rule violation during cognitive testing remains debated. The current study examined the neuroanatomical correlates of rule violation (RV) errors made on tests of executive functioning in 166 subjects diagnosed with neurodegenerative disease or as neurologically healthy. Specifically, RV errors were voxel-wisely correlated with gray matter volume derived from high-definition MR images using voxel-based morphometry implemented in SPM2. Latent variable analysis showed that rule violation errors tapped a unitary construct separate from repetition errors. This analysis was used to generate factor scores to represent what is common among rule violation errors across tests. The extracted rule violation factor scores correlated with tissue loss in the lateral middle and inferior frontal gyri and the caudate nucleus bilaterally. When a more stringent control for global cognitive functioning was applied using Mini Mental State Exam scores, only the correlations with the right lateral prefrontal cortex remained significant. These data underscore the importance of right lateral prefrontal cortex in behavioral monitoring and highlight the potential of rule violation error assessment for identifying patients with damage to this region

Comparison of prefrontal atrophy and episodic memory performance in dysexecutive Alzheimer’s disease and behavioural-variant frontotemporal dementia

Alzheimer’s disease (AD) sometimes presents with prominent executive dysfunction and associated prefrontal cortex atrophy. The impact of such executive deficits on episodic memory performance as well as their neural correlates in AD, however, remains unclear. The aim of the current study was to investigate episodic memory and brain atrophy in AD patients with relatively spared executive functioning (SEF-AD; n = 12) and AD patients with relatively impaired executive functioning (IEF-AD; n = 23). We also compared the AD subgroups with a group of behavioral-variant frontotemporal dementia patients (bvFTD; n = 22), who typically exhibit significant executive deficits, and age-matched healthy controls (n = 38). On cognitive testing, the three patient groups showed comparable memory profiles on standard episodic memory tests, with significant impairment relative to controls. Voxel-based morphometry analyses revealed extensive prefrontal and medial temporal lobe atrophy in IEF-AD and bvFTD, whereas this was limited to the middle frontal gyrus and hippocampus in SEF-AD. Moreover, the additional prefrontal atrophy in IEF-AD and bvFTD correlated with memory performance, whereas this was not the case for SEF-AD. These findings indicate that IEF-AD patients show prefrontal atrophy in regions similar to bvFTD, and suggest that this contributes to episodic memory performance. This has implications for the differential diagnosis of bvFTD and subtypes of AD

Visuospatial Functioning In The Primary Progressive Aphasias

Objectives: The aim of this study was to identify whether the three main primary progressive aphasia (PPA) variants would show differential profiles on measures of visuospatial cognition. We hypothesized that the logopenic variant would have the most difficulty across tasks requiring visuospatial and visual memory abilities. Methods: PPA patients (n = 156), diagnosed using current criteria, and controls were tested on a battery of tests tapping different aspects of visuospatial cognition. We compared the groups on an overall visuospatial factor; construction, immediate recall, delayed recall, and executive functioning composites; and on individual tests. Cross-sectional and longitudinal comparisons were made, adjusted for disease severity, age, and education. Results: The logopenic variant had significantly lower scores on the visuospatial factor and the most impaired scores on all composites. The nonfluent variant had significant difficulty on all visuospatial composites except the delayed recall, which differentiated them from the logopenic variant. In contrast, the semantic variants performed poorly only on delayed recall of visual information. The logopenic and nonfluent variants showed decline in figure copying performance over time, whereas in the semantic variant, this skill was remarkably preserved. Conclusions: This extensive examination of performance on visuospatial tasks in the PPA variants solidifies some previous findings, for example, delayed recall of visual stimuli adds value in differential diagnosis between logopenic variant PPA and nonfluent variant PPA variants, and illuminates the possibility of common mechanisms that underlie both linguistic and non-linguistic deficits in the variants. Furthermore, this is the first study that has investigated visuospatial functioning over time in the PPA variants

Sub-retinal pigment epithelial deposits in a dominant late-onset retinal degeneration

Purpose. To determine the pathogenesis of an autosomal dominant late-onset retinal degeneration by studies of the retinal histopathology, phenotype of family members, and candidate genes for the disease. Methods. The retina from an 80-year-old patient donor was prepared for light and electron microscopy, including special stains and immunocytochemistry. Family members were examined clinically and with retinal function tests. Rhodopsin, peripherin//?DS, and TIMP3 genes were screened for mutations, and linkage analysis was performed with short tandem repeat polymorphisms flanking these genes. Results. Affected family members had nyctalopia in the sixth decade of life and severe visual loss developed by the eighth decade. The donor retina showed marked loss of photoreceptors except in the inferior periphery. A thick layer of extracellular deposits was present between the RPE and Bruch's membrane in all retinal regions. A 70-year-old affected family member had a retinopathy resembling retinitis pigmentosa. Her 42-year-old daughter had a patch of punctate yellow-white lesions in one fundus and abnormal dark adaptation. The 50-year-old son of the donor had normal fundi but abnormal dark adaptation and electroretinography. No mutations were detected in the coding sequence of the rhodopsin, peripherin/ilDS, and TIMP3 genes. Rhodopsin and TIMP3 were further excluded with linkage analysis. Conclusions. This novel retinal degeneration shares histopathologic and clinical features with both Sorsby fundus dystrophy and retinitis pigmentosa. The sub-RPE deposits may disrupt the exchange of nutrients and metabolites between the retina and the choriocapillaris, leading to photoreceptor dysfunction and degeneration. Invest Ophthalmol Vis Sci. 1996; 37:1772-1782 .LJeposits between the retinal pigment epithelium (RPE) and Bruch's membrane are characteristic of age-related macular degeneration (ARMD) 1 and Sorsby fundus dystrophy (SFD) . 2 It has been hypothesized 3 A that such sub-RPE deposits may disrupt transport processes between the choriocapillaris and photoreceptors and lead to loss of vision. We obtained the eyes of a patient donor from