Confabulations usually refer to memory distortions, characterized by the production of verbal statements or actions that are inconsistent with the patient's history and present situation. However, behavioral patterns reminiscent of memory confabulations can also occur in patients with right hemisphere damage, in relation to their personal, peripersonal or extrapersonal space. Thus, such patients may be unaware of their left hemiplegia and confabulate about it (anosognosia), deny the ownership of their left limbs (somatoparaphrenia), insult and hit them (misoplegia), or experience a "third", supernumerary left limb. Right brain-damaged patients can also sometimes confabulate about the left, neglected part of images presented in their peripersonal space, or believe to be in another place (reduplicative paramnesia). We review here these instances of confabulation occurring after right hemisphere damage, and propose that they might reflect, at least partially, the attempts of the left hemisphere to make sense of inappropriate input received from the damaged right hemisphere.
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http://dx.doi.org/10.1016/j.cortex.2016.07.007 | DOI Listing |
Alzheimers Dement
December 2024
University of California, Irvine, Irvine, CA, USA.
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View Article and Find Full Text PDFAlzheimers Dement
December 2024
University of Pittsburgh, Pittsburgh, PA, USA.
Background: Employing a custom 60-channel single-transmit/32-channel receive Tic-Tac-Toe (TTT) coil in 7T MRI imaging has enhanced the resolution and contrast for identifying White Matter Hyperintensities (WMHs), which are critical markers in Alzheimer's disease and related dementias (AD/ADRD).
Method: The method involves resecting the left hemisphere of the brain, excluding the cerebellum, followed by embalming in 10% formalin. 1.
Alzheimers Dement
December 2024
University of California San Francisco, San Francisco, CA, USA.
Background: Despite the prevalent belief that socioemotional processing remains mostly intact in the early stages of Alzheimer's disease (AD), impaired Theory of Mind - the ability to understand and interpret others' thoughts, beliefs, and feelings - has been observed in persons with AD. During everyday conversations, the high cognitive loading of socioemotional interactions may adversely impact the ability of persons with AD to identify emotions and read others' intentions. This study aimed to investigate socioemotional perception capabilities in early-stage AD and to determine whether cerebellar and cerebral integrity predicts performance on socioemotional perception tests.
View Article and Find Full Text PDFNeuroimage
December 2024
F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA; Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA. Electronic address:
This study aims to investigate the variations in guanidino (Guan), amine and amide chemical exchange saturation transfer (CEST) contrasts in ischemic stroke using permanent middle cerebral artery occlusion (pMCAO) and transient MCAO (tMCAO) models at high (9.4T) and clinical (3T) MRI fields. CEST contrasts were extracted using the Polynomial and Lorentzian Line-shape Fitting (PLOF) method.
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