Primate brain MRI

B-ENT. 2012; 8(4): 289-94 Verhoeven S, De Ridder D, Venstermans C, Van de Heyning P A 62-year-old man complaining of vertigo and progressive hearing loss was diagnosed with an arachnoid cyst at the right cerebellopontine angle based on magnetic resonance imaging (MRI). In this case-report, we used computed tomography (CT) cisternography to determine whether the arachnoid cyst communicated with the cerebrospinal fluid (CSF) space. Differentiating between a noncommunicating and communicating arachnoid cyst is required for presurgical evaluation. CT cisternography is a less used but reliable radiological technique for determining the presence of communication, and could therefore be included in the diagnostic work-up of arachnoid cysts. The patient underwent surgery with fenestration of the arachnoid cyst; his vertigo improved and his hearing was preserved.

Southeast Asian J Trop Med Public Health. 2012 Sep; 43(5): 1201-4 Ittyachen AM, Jose MB We report a case of a Russell's viper (Daboia russelii) bite involving a 55-year-old male who developed a bilateral thalamic infarction. Although the coagulopathy was controlled within twenty-four hours, the patient became restless and disoriented. Due to the initial prolonged clotting time, we suspected an intracranial bleed. T2 magnetic resonance imaging (MRI) of the brain showed bilateral infarcts of the thalamus. Cerebral infarction secondary to snake envenomation has been reported before, but to our knowledge bilateral involvement of the thalamus has not been reported.

Laeknabladid. 2013 Jan; 99(1): 25-31 Sveinsson OA, Asgeirsson H, Olafsson IH Brain abscess is a life threatening illness, demanding rapid diagnosis and treatment. Its development requires seeding of an organism into the brain parenchyma, often in an area of damaged brain tissue or in a region with poor microcirculation. The lesion evolves from a cerebritis stage to capsule formation. Brain abscesses can be caused by contiguous or haematogenous spread of an infection, or by head trauma/ neurosurgical procedure. The most common presentation is that of headache and vomiting due to raised intracranial pressure. Seizures have been reported in up to 50% of cases. Focal neurological deficits may be present, depending on the location of the lesion. Treatment of a brain abscess involves aspiration or excision, along with parenteral antibiotic therapy. The outcome has improved dramatically in the last decades due to improvement in diagnostic techniques, neurosurgery, and broad-spectrum...

J Neurosci. 2013 Jan 9; 33(2): 611-23 Tidoni E, Borgomaneri S, di Pellegrino G, Avenanti A The ability to infer deceptive intents from nonverbal behavior is critical for social interactions. By combining single-pulse and repetitive transcranial magnetic stimulation (TMS) in healthy humans, we provide both correlational and causative evidence that action simulation is actively involved in the ability to recognize deceptive body movements. We recorded motor-evoked potentials during a faked-action discrimination (FAD) task: participants watched videos of actors lifting a cube and judged whether the actors were trying to deceive them concerning the real weight of the cube. Seeing faked actions facilitated the observers' motor system more than truthful actions in a body-part-specific manner, suggesting that motor resonance was sensitive to deceptive movements. Furthermore, we found that TMS virtual lesion to the anterior node of the action observation network, namely the left inferior...

J Neurosci. 2013 Jan 9; 33(2): 523-31 Zaretskaya N, Anstis S, Bartels A Grouping local elements into a holistic percept, also known as spatial binding, is crucial for meaningful perception. Previous studies have shown that neurons in early visual areas V1 and V2 can signal complex grouping-related information, such as illusory contours or object-border ownerships. However, relatively little is known about higher-level processes contributing to these signals and mediating global Gestalt perception. We used a novel bistable motion illusion that induced alternating and mutually exclusive vivid conscious experiences of either dynamic illusory contours forming a global Gestalt or moving ungrouped local elements while the visual stimulation remained the same. fMRI in healthy human volunteers revealed that activity fluctuations in two sites of the parietal cortex, the superior parietal lobe and the anterior intraparietal sulcus (aIPS), correlated specifically with the perception of the...

J Neurosci. 2013 Jan 9; 33(2): 387-96 Gold BT, Kim C, Johnson NF, Kryscio RJ, Smith CD Recent behavioral data have shown that lifelong bilingualism can maintain youthful cognitive control abilities in aging. Here, we provide the first direct evidence of a neural basis for the bilingual cognitive control boost in aging. Two experiments were conducted, using a perceptual task-switching paradigm, including a total of 110 participants. In Experiment 1, older adult bilinguals showed better perceptual switching performance than their monolingual peers. In Experiment 2, younger and older adult monolinguals and bilinguals completed the same perceptual task-switching experiment while functional magnetic resonance imaging (fMRI) was performed. Typical age-related performance reductions and fMRI activation increases were observed. However, like younger adults, bilingual older adults outperformed their monolingual peers while displaying decreased activation in left lateral frontal cortex and...

Neurology. 2013 Jan 8; 80(2): e13-6 Mendoza M, Latorre JG Ondine's curse is an eponym that refers to central alveolar apnea/hypopnea observed among patients with acquired or congenital brainstem disorders. This condition results in loss of automatic and/or voluntary respiration with characteristic polysomnographic finding of impaired ventilator responses to hypercapnia and sleep apnea, which are more pronounced during non-REM sleep, less in REM sleep, and least during wakefulness.

Neurology. 2013 Jan 8; 80(2): e21 Gasparini S, Ferlazzo E, Branca D, Labate A, Cianci V, Latella MA, Aguglia U A 43-year-old woman presented with 1 month of progressive lower limb burning sensation, blurred vision, and gait disturbance. Her mother died of Creutzfeldt-Jakob disease (CJD). Neurologic examination revealed only cerebellar ataxia. EEG revealed periodic generalized discharges. MRI (figure 1) showed FLAIR hyperintensity in caudate and lenticular nuclei. Molecular analysis confirmed genetic CJD (PRNP E200K mutation). One month later, she became comatose. After 10 months, EEG showed diffuse background flattening without periodic abnormalities, and MRI (figure 2) disclosed diffuse pseudohypertrophy of cerebral cortex. MRI in this patient with end-stage CJD allowed us to reveal in vivo the macroscopic spongiform changes usually observed at autopsy.

Proc Natl Acad Sci U S A. 2012 Dec 11; 109(50): 20738-43 Barton B, Venezia JH, Saberi K, Hickok G, Brewer AA The functional organization of human auditory cortex has not yet been characterized beyond a rudimentary level of detail. Here, we use functional MRI to measure the microstructure of orthogonal tonotopic and periodotopic gradients forming complete auditory field maps (AFMs) in human core and belt auditory cortex. These AFMs show clear homologies to subfields of auditory cortex identified in nonhuman primates and in human cytoarchitectural studies. In addition, we present measurements of the macrostructural organization of these AFMs into "clover leaf" clusters, consistent with the macrostructural organization seen across human visual cortex. As auditory cortex is at the interface between peripheral hearing and central processes, improved understanding of the organization of this system could open the door to a better understanding of the transformation from auditory...

BMJ. 2013; 346: e8702 Walsh F, Simmonds F, Young GB, Owen AM

J Cardiovasc Surg (Torino). 2013 Feb; 54(1): 93-9 Rosenkranz M, Gerloff C Carotid artery stenting is associated with the risk of periprocedural stroke. Moreover, modern magnetic resonance (MR) imaging techniques have found high rates of clinically silent ischemic brain lesions on post-treatment diffusion-weighted MR imaging (DWI) scans. The clinical significance of procedure-related DWI lesions, however, is still a matter of debate. This review article considers the frequency, location and pathophysiology of new DWI lesions on post-treatment MR images and summarizes available data on their clinical significance.

J Neurosci. 2013 Feb 20; 33(8): 3259-3275 Mantini D, Corbetta M, Romani GL, Orban GA, Vanduffel W Primate evolution has been accompanied by complex reorganizations in brain anatomy and function. Little is known, however, about the relationship between anatomical and functional changes induced through primate evolution. Using functional magnetic resonance imaging, we assessed spatial and temporal correspondences of cortical networks in humans and monkeys. We provided evidence for topologically and functionally correspondent networks in sensory-motor and attention regions. More specifically, we revealed a possible monkey equivalent of the human ventral attention network. For other human networks, such as the language and the default-mode networks, we detected topological correspondent networks in the monkey, but with different functional signatures. Furthermore, we observed two lateralized human frontoparietal networks in the cortical regions displaying the greatest evolutionary...

J Neurosci. 2012 Nov 28; 32(48): 17351-64 Quallo MM, Kraskov A, Lemon RN It has been suggested that the distinctive capacity of some nonhuman primates to use tools may reflect a well-developed corticospinal system and, in particular, direct cortico-motoneuronal (CM) connections to hand muscles. We investigated the activity of corticospinal neurons in the primary motor cortex hand area during the use of a tool by two adult macaque monkeys. They used a light rake to retrieve food rewards placed in their extrapersonal space. An analysis of EMG activity showed that the rake task involved a complex interaction of muscles acting on the digits, hand, and arm. Sixty-nine corticospinal neurons were identified antidromically as pyramidal tract neurons (PTNs). When tested on the rake task, most (64 of 69; 93%) showed a significant modulation of their discharge during at least one of three task periods: grasping the rake, projecting it beyond the food reward, and then pulling it back to retrieve...

Top Stroke Rehabil. 2013 Jan-Feb; 20(1): 5-21 Cherney LR, Babbitt EM, Hurwitz R, Rogers LM, Stinear J, Wang X, Harvey RL, Parrish T To illustrate the ethical challenges that arose from investigating a novel treatment procedure, transcranial direct current stimulation (tDCS), in a research participant with aphasia.We review the current evidence supporting the use of tDCS in aphasia research, highlighting methodological gaps in our knowledge of tDCS. Then, we examine the case of Mr. C, a person with chronic aphasia who participated in a research protocol investigating the impact of tDCS on aphasia treatment. We describe the procedures that he underwent and the resulting behavioral and neurophysiological outcomes. Finally, we share the steps that were taken to balance beneficence and nonmaleficence and to ensure Mr. C's autonomy.The objective data show that while Mr. C may not have benefitted from participating in the research, neither did he experience any harm.Researchers must consider...

Am J Psychiatry. 2013 Jan 1; 170(1): 122-3 Rane S, Kose S, Gore JC, Heckers S

J Clin Psychiatry. 2012 Nov; 73(11): e30 Jain R, Jackson WC For patients with depression, antidepressant response rates are generally low and residual symptoms can increase the risk of relapse. Poor response may be linked to increased inflammatory cytokines and obesity. Specifically targeting inflammation with adjunct l-methylfolate treatment may help patients with depression finally achieve remission. In this Webcast, experts examine the multi-directional relationship between obesity, inflammation, and depression, consider preliminary data on genetic alleles, and review evidence using l-methylfolate as a targeted therapy.