Imagined Musical Scale Relationships Decoded from Auditory Cortex.

Notes in a musical scale convey different levels of stability or incompleteness, forming what is known as a tonal hierarchy. Levels of stability conveyed by these scale degrees are partly responsible for generating expectations as a melody proceeds, for emotions deriving from fulfillment (or not) of those expectations, and for judgments of overall melodic well-formedness. These functions can be extracted even during imagined music. We investigated whether patterns of neural activity in fMRI could be used to identify heard and imagined notes, and if patterns associated with heard notes could identify notes that were merely imagined. We presented trained musicians with the beginning of a scale (key and timbre were varied). The next note in the scale was either heard or imagined. A probe tone task assessed sensitivity to the tonal hierarchy, and state and trait measures of imagery were included as predictors. Multivoxel classification yielded above-chance results in primary auditory cortex (Heschl's gyrus) for heard scale-degree decoding. Imagined scale-degree decoding was successful in multiple cortical regions spanning bilateral superior temporal, inferior parietal, precentral, and inferior frontal areas. The right superior temporal gyrus yielded successful cross-decoding of heard-to-imagined scale-degree, indicating a shared pathway between tonal-hierarchy perception and imagery. Decoding in right and left superior temporal gyrus and right inferior frontal gyrus was more successful in people with more differentiated tonal hierarchies and in left inferior frontal gyrus among people with higher self-reported auditory imagery vividness, providing a link between behavioral traits and success of neural decoding. These results point to the neural specificity of imagined auditory experiences-even of such functional knowledge-but also document informative individual differences in the precision of that neural response.

Evaluation of imaging-guided core biopsy of pancreatic masses.

OBJECTIVE: The purpose of this study was to determine the sensitivity and accuracy of imaging-guided core biopsy in the diagnosis of pancreatic masses. CONCLUSION: Imaging-guided core biopsy is sensitive, safe, and accurate in the diagnosis of malignant lesions of the pancreas. Benign biopsy findings cannot be used to exclude the presence of a neoplasm, and repetition of a biopsy should be considered if there is high clinical suspicion of malignancy.

Changing role of imaging-guided percutaneous biopsy of adrenal masses: evaluation of 50 adrenal biopsies.

OBJECTIVE: Prior series of percutaneous imaging-guided biopsies of adrenal masses before the advent of dedicated CT and MRI of the adrenal glands have shown that 40-57% of adrenal masses biopsied were adenomas-benign lesions requiring no further evaluation or treatment. This study was performed to assess the effect of dedicated adrenal imaging with CT and MRI on the rate of percutaneous imaging-guided biopsies of adrenal masses. MATERIALS AND METHODS: We reviewed 50 consecutive adrenal mass biopsies performed during a 48-month period. The patient demographics, technique of biopsy, pathology results, and results of any prior dedicated adrenal imaging with MRI or CT protocols were noted. RESULTS: Only six (12%) of 50 biopsies were adenomas. Five of these six cases were preceded by dedicated adrenal CT or MRI. Thirty-five cases were metastatic disease, four were adrenal cortical carcinoma, three were pheochromocytoma, and two biopsies were nondiagnostic. Overall, 20 of 50 cases were preceded by a dedicated adrenal CT or MRI examination to exclude an adenoma; in 21 of the remaining 30 cases, the imaging characteristics before biopsy were inconsistent with the potential diagnosis of an adenoma and dedicated adrenal CT or MRI was not recommended. CONCLUSION: The number of adrenal adenomas biopsied has declined markedly with the introduction of dedicated adrenal CT and MRI for adrenal adenomas. Percutaneous imaging-guided biopsy is useful in confirming the presence and nature of suspected metastatic deposits to the adrenal gland and in diagnosing or excluding adrenal adenomas in patients with equivocal imaging characteristics.