We propose that cerebrovascular disease may predispose, precipitate, or perpetuate some geriatric depressive syndromes. The "vascular depression" hypothesis is supported by the comorbidity of depression, vascular disease, and vascular risk factors and the association of ischemic lesions to distinctive behavioral symptoms. Disruption of prefrontal systems or their modulating pathways by single lesions or by an accumulation of lesions exceeding a threshold are hypothesized to be central mechanisms in vascular depression. The vascular depression concept can generate studies of clinical and heuristic value. Drugs used for the prevention and treatment of cerebrovascular disease may be shown to reduce the risk for vascular depression or improve its outcomes. The choice of antidepressants in vascular depression may depend on their effect on neurologic recovery from ischemic lesions. Research can clarify the pathways to vascular depression by focusing on the site of the lesion, the resultant brain dysfunction, the presentation of depression and time of onset, and the contribution of nonbiological factors.

'Vascular depression' hypothesis.

The neural correlates of music perception were studied by measuring cerebral blood flow (CBF) changes with positron emission tomography (PET). Twelve volunteers were scanned using the bolus water method under four separate conditions: (1) listening to a sequence of noise bursts, (2) listening to unfamiliar tonal melodies, (3) comparing the pitch of the first two notes of the same set of melodies, and (4) comparing the pitch of the first and last notes of the melodies. The latter two conditions were designed to investigate short-term pitch retention under low or high memory load, respectively. Subtraction of the obtained PET images, superimposed on matched MRI scans, provides anatomical localization of CBF changes associated with specific cognitive functions. Listening to melodies, relative to acoustically matched noise sequences, resulted in CBF increases in the right superior temporal and right occipital cortices. Pitch judgments of the first two notes of each melody, relative to passive listening to the same stimuli, resulted in right frontal-lobe activation. Analysis of the high memory load condition relative to passive listening revealed the participation of a number of cortical and subcortical regions, notably in the right frontal and right temporal lobes, as well as in parietal and insular cortex. Both pitch judgment conditions also revealed CBF decreases within the left primary auditory cortex. We conclude that specialized neural systems in the right superior temporal cortex participate in perceptual analysis of melodies; pitch comparisons are effected via a neural network that includes right prefrontal cortex, but active retention of pitch involves the interaction of right temporal and frontal cortices.

https://www.jneurosci.org/content/jneuro/14/4/1908.full.pdf

Neural mechanisms underlying melodic perception and memory for pitch.

The yield of alkenols and cycloalkenols is substantially improved by carrying out the reaction of olefins with formaldehyde in the presence of selected catalysts. In accordance with one embodiment, alk-3-en-1-ols are produced in good yields from isobutylene and formaldehyde in the presence of organic carboxylic acid salts of Group IB metals.

The Organization of the Cochlear Receptor

Recent work has indicated that the insula may be involved in goal-directed cognition, switching between networks, and the conscious awareness of affect and somatosensation. However, these findings have been limited by the insula's remarkably high base rate of activation and considerable functional heterogeneity. The present study used a relatively unbiased data-driven approach combining resting-state connectivity-based parcellation of the insula with large-scale meta-analysis to understand how the insula is anatomically organized based on functional connectivity patterns as well as the consistency and specificity of the associated cognitive functions. Our findings support a tripartite subdivision of the insula and reveal that the patterns of functional connectivity in the resting-state analysis appear to be relatively conserved across tasks in the meta-analytic coactivation analysis. The function of the networks was meta-analytically "decoded" using the Neurosynth framework and revealed that while the dorsoanterior insula is more consistently involved in human cognition than ventroanterior and posterior networks, each parcellated network is specifically associated with a distinct function. Collectively, this work suggests that the insula is instrumental in integrating disparate functional systems involved in processing affect, sensory-motor processing, and general cognition and is well suited to provide an interface between feelings, cognition, and action.

/pdf/decoding-the-role-of-the-insula-in-human-cognition-wiyg6scj8x.pdf

Decoding the Role of the Insula in Human Cognition: Functional Parcellation and Large-Scale Reverse Inference

Objective. Sudden hearing loss (SHL) is a frightening symptom that often prompts an urgent or emergent visit to a physician. This guideline provides evidence-based recommendations for the diagnosis...

/pdf/clinical-practice-guideline-sudden-hearing-loss-8acwe9fo8a.pdf

Clinical practice guideline: sudden hearing loss.

Sharon Abel, PhD Jane Baran, PhD Anthony Cacace, PhD Gail Chermak, PhD$ Susan Dalebout, PhD Jay Hall 111, PhD Linda Hood, PhD Lisa Hunter, PhD James Jerger, PhD Susan Jerger, PhD Robert Keith, PhD Frank Musiek, PhD Ross Roeser, PhD Christine Sloan, PhD University of Toronto, Toronto, ON University of Massachusetts, Amherst, MA Albany Medical College, Albany, NY Washington State University, Pullman, WA University of Virginia, Charlottesville,VA University of Florida, Gainesville, FL Louisiana State University Medical Center, New Orleans, LA University of Minnesota, Minneapolis, MN University of Texas at Dallas, Dallas, TX University of Texas at Dallas, Dallas, TX University of Cincinnati, Cincinnati, OH Dartmouth-Hitchcock Medical Center, Hanover, NH University of Texas at Dallas, Dallas, TX Annapolis Valley Regional School Board Berwick, NS

Report of the Consensus Conference on the Diagnosis of Auditory Processing Disorders in School-Aged Children.

The insula (Island of Reil) and its role in auditory processing. Literature review.

CONTENTSForeword by Dennis P. Phillips, Ph.D. Conceptual and Historical Foundations. Neurobiology of the Central Auditory Nervous System Relevant to Central Auditory Processing. Spoken Language Processing. Considerations in the Assessment of Central Auditory Processing Disorders. Behavioral Central Auditory Tests. Electrophysiologic Assessment of Central Auditory Processing Disorders. Fundamental Concepts and Considerations for Management. Management: Auditory Training and Metalinguistic and Metacognitive Strategies. Enhancing the Acoustic Signal and the Listening Environment. Research Needs and Future Directions. Glossary. References. Index.

Central Auditory Processing Disorders: New Perspectives

A dichotic digit test was administered to 21 subjects with intracranial lesions. Twelve subjects had lesions limited to the cortex and nine had brain stem disorders. The dichotic digit test appeared to be a sensitive measure for detecting cortex and brain stem lesions. Laterality data indicated markedly reduced performance for the ear contralateral to the hemispheric lesion. Overall results were similar to previous reports on dichotic digits, supporting the use of this test as a screening procedure or part of a test battery for CNS evaluation.

Assessment of central auditory dysfunction: the dichotic digit test revisited.

Objective: The purpose of the present study was to investigate the value of a new gap detection procedure called Gaps-In-Noise (GIN) for assessment of temporal resolution in a clinical population. Design: The test consists of 0 to 3 silent intervals ranging from 2 to 20 msec embedded in 6-sec segments of white noise. The location, number, and duration of the gaps per noise segment vary throughout the test for a total of 60 gaps presented in each of four lists. The GIN procedure was administered to 50 normal-hearing listeners (group I) and 18 subjects with confirmed neurological involvement of the central auditory nervous system (group II). Results: Results showed mean approximated gap detection thresholds of 4.8 msec for the left ear and 4.9 msec for the right ear for group I. In comparison, results for group II demonstrated a statistically significant increase in gap detection thresholds, with approximated thresholds of 7.8 msec and 8.5 msec being noted for the left and right ears, respectively. Significant mean differences were also observed in the overall performance scores (i.e., the identification of the presence of the gaps within the noise segments) of the two groups of subjects. Finally, psychometric functions, although similar for short and long duration gaps, were highly different for gaps in the 4- to 10-msec range for the two groups. Conclusions: A variety of psychoacoustic procedures are available to assess temporal resolution; however, the clinical use of these procedures is minimal at best. Results of the present study show that the GIN test holds promise as a clinically useful tool in the assessment of temporal resolution in the clinical arena.

Frank E. Musiek

Papers

Report of the Consensus Conference on the Diagnosis of Auditory Processing Disorders in School-Aged Children.

The insula (Island of Reil) and its role in auditory processing. Literature review.

Central Auditory Processing Disorders: New Perspectives

Assessment of central auditory dysfunction: the dichotic digit test revisited.

GIN (Gaps-In-Noise) test performance in subjects with confirmed central auditory nervous system involvement (vol 26, pg 608, 2005)