The present study compared the effects of fornix lesions and medial prefrontal lesions on a test of object recognition memory, delayed non-matching-to-sample. Neither lesion impaired the acquisition of this non-spatial test of working memory, indeed there was clear evidence that fornix damage resulted in improved non-matching performance during initial acquisition. This improvement in performance could be related to the loss of a spatial bias during the early stages of training. A series of experiments then systematically increased the familiarity of the stimuli (i.e. testing recency rather than recognition judgements). Neither the fornix nor the prefrontal lesions disrupted performance under these conditions, even though this manipulation affected nonmatching in a predictable manner. The same animals were also tested on a spatial forced-alternation task in a T-maze (spatial delayed non-matching-to-sample). The animals with fornix lesions performed at chance while the prefrontal animals were mildly, but significantly, impaired. The present findings are considered in the light of a number of seemingly contradictory findings regarding the effects of hippocampal system damage on nonspatial tests of recognition memory.
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http://dx.doi.org/10.1016/0166-4328(93)90051-q | DOI Listing |
Epilepsia
January 2025
Department of Epileptology and Cerebral Rhythmology, APHM, Timone Hospital, Marseille, France.
Objective: Lennox-Gastaut syndrome (LGS) is typically characterized by drug-resistant epilepsy and subsequent cognitive deterioration. Surgery is a rare but viable option for the control of seizures in a subset of patients with LGS. This study aimed to describe the organization of the epileptogenic zone network (EZN) in patients with LGS using stereoelectroencephalography (SEEG) and to report the outcome of post-SEEG treatment.
View Article and Find Full Text PDFNeuroimage
January 2025
High-Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria; Christian Doppler Laboratory for MR Imaging Biomarkers (BIOMAK), Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria.
Objectives: To assess topographical patterns of metabolic abnormalities in the cerebrum of multiple sclerosis (MS) patients and their relationship to clinical disability using rapid echo-less 3D-MR spectroscopic imaging (MRSI) at 7T.
Materials And Methods: This study included 26 MS patients (13 women; median age 34) and 13 age- and sex-matched healthy controls (7 women; median age 33). Metabolic maps were obtained using echo-less 3D-MRSI at 7T with a 64 × 64 × 33 matrix and a nominal voxel size of 3.
Exp Neurol
January 2025
Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an 710061, China. Electronic address:
Depression is one of the most common non-motor symptoms in Parkinson's disease (PD) and the hyperactivity of the lateral habenula (LHb) may contribute to depression. The present study was performed to investigate the effects and mechanisms of group I metabotropic glutamate receptors (mGluRs) in the LHb on PD-related depressive-like behaviors. Unilateral 6-hydroxydopamine lesions of the substantia nigra pars compacta (SNc) were used to establish the PD rat model.
View Article and Find Full Text PDFAim: The Transorbital and supraorbital minimally invasive approaches have been defined to reach intraorbital structures, adjacent sinuses, skull base, and other intracranial targets in this region. These approaches reduce the possible cosmetic and brain retraction-related morbidities caused by traditional transcranial approaches. Although these pathways are being studied endoscopically, a stereotactic approach has not been defined.
View Article and Find Full Text PDFAlzheimers Dement
January 2025
Guangdong Provincial Key Laboratory of Brain Function and Disease, Center for Brain and Mental Well-Being, Department of Psychology, Sun Yat-sen University, Guangzhou, China.
Introduction: Visual short-term memory (VSTM) is a critical indicator of Alzheimer's disease (AD), but whether its neural substrates could adapt to early disease progression and contribute to cognitive resilience in amnestic mild cognitive impairment (aMCI) has been unclear.
Methods: Fifty-five aMCI patients and 68 normal controls (NC) performed a change-detection task and underwent multimodal neuroimaging scanning.
Results: Among the atrophic brain regions in aMCI, VSTM performance correlated with the volume of the right prefrontal cortex (PFC) but not the medial temporal lobe (MTL), and this correlation was mainly present in patients with greater MTL atrophy.
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