Alongside stereotactic magnetic resonance imaging, microelectrode recording (MER) is frequently used during the deep brain stimulation (DBS) surgery for optimal target localization. The aim of this study is to optimize subthalamic nucleus (STN) mapping using MER analytical patterns. 16 patients underwent bilateral STN-DBS. MER was performed simultaneously for 5 microelectrodes in a setting of Ben’s-gun pattern in awake patients. Using spikes and background activity several different parameters and their spectral estimates in various frequency bands including low frequency (2–7 Hz), Alpha (8–12 Hz), Beta (sub-divided as Low_Beta (13–20 Hz) and High_Beta (21–30 Hz)) and Gamma (31 to 49 Hz) were computed. The optimal STN lead placement with the most optimal clinical effect/side-effect ratio accorded to the maximum spike rate in 85% of the implantation. Mean amplitude of background activity in the low beta frequency range was corresponding to right depth in 85% and right location in 94% of the implantation respectively. MER can be used for STN mapping and intraoperative decisions for the implantation of DBS electrode leads with a high accuracy. Spiking and background activity in the beta range are the most promising independent parameters for the delimitation of the proper anatomical site.

Background:Primary intraosseous cavernous hemangiomas (PICH) of the skull represent an infrequent bone tumor. Although some rare cases of PICHs located in the skull base have been published, to our concern only three cases have been reported in the English literature of PICHs arising within the clivus.Case Description:We present the case of a patient presenting an isolated abducens paresis due to a rare PICH of the clivus showing also an unusual destruction of the inner table as well as infiltration of the dura mater. Due to this uncommon infiltrative pattern of an otherwise expected intraosseous tumor, a cerebrospinal fluid (CSF)-fistula occurred while performing a transnasal biopsy. The patient recovered successfully without need of lumbar drainage or re-surgery. Additionally, intratumoral decompression was sufficient to relief the abducens paresis.Conclusions:Our case provides new and meaningful information about clinical features as well as growth pattern of these rare clival tumors. We also discuss the importance of knowing these peculiarities before surgery in order to plan the optimal operative management as well as to avoid complications while approaching PICHs localized in such a delicate cranial region.

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Glycine transporter 1 (GlyT1) is a potential pharmacological target to ameliorate memory deficits attributable to N-methyl-d-aspartate receptor (NMDAR) hypofunction. Disruption of glycine-reuptake near excitatory synapses is expected to enhance NMDAR function by increasing glycine-B site occupancy. Genetic models with conditional GlyT1 deletion restricted to forebrain neurons have yielded several promising promnesic effects, yet its impact on working memory function remains essentially unanswered because a previous attempt had yielded un-interpretable outcomes. The present study clarified this important outstanding lacuna using a within-subject multi-paradigm approach. Here, a consistent lack of effects was convincingly demonstrated across three working memory test paradigms – the radial arm maze, the cheeseboard maze, and the water maze. These null outcomes contrasted with the phenotype of enhanced working memory performance seen in mutant mice with GlyT1 deletion extended to cortical/hippocampal glial cells. It follows that glial-based GlyT1 might be more closely linked to the modulation of working memory function, and raises the possibility that neuronal and glial GlyT1 may regulate cognitive functions via dissociable mechanisms.