The development of controllable and reproducible animal models of intracerebral hemorrhage (ICH) is essential for the systematic study of the pathophysiology and treatment of hemorrhagic stroke. In recent years, we have used a modified version of a murine ICH model to inject blood into mouse basal ganglia. According to our protocol, autologous blood is stereotactically infused in two stages into the right striatum to mimic the natural events of hemorrhagic stroke. Following ICH induction, animals demonstrate reproducible hematomas, brain edema formation and marked neurological deficits. Our technique has proven to be a reliable and reproducible means of creating ICH in mice in a number of acute and chronic studies. We believe that our model will serve as an ideal paradigm for investigating the complex pathophysiology of hemorrhagic stroke. The protocol for establishing this model takes about 2 h.

Despite a substantial body of work comprising theoretical modeling, the effects of medial temporal lobe lesions, and electrophysiological signal analysis, the role of the hippocampus in recognition memory remains controversial. In particular, it is not known whether the hippocampus exclusively supports recollection or both recollection and familiarity-the two latent cognitive processes theorized to underlie recognition memory. We studied recognition memory in a large group of patients undergoing intracranial electroencephalographic (iEEG) monitoring for epilepsy. By measuring high-frequency activity (HFA)-a signal associated with precise spatiotemporal properties-we show that hippocampal activity during recognition predicted recognition memory performance and tracked both recollection and familiarity. Through the lens of dual-process models, these results indicate that the hippocampus supports both the recollection and familiarity processes.hippocampus | recognition memory | recollection | familiarity | high-frequency activity R ecognition is one's ability to judge an item as previously encountered. Whereas it is well known that the hippocampus plays a crucial role in human recall memory, the role of the hippocampus in recognition memory remains surprisingly controversial (1-4). A number of studies have reported that bilateral hippocampal injury in humans causes impaired recall, whereas recognition remains intact (5). Others document the preservation of recognition in the setting of hippocampal lesioning in nonhuman primates (6) and rodents (7). On the other hand, a substantial literature describes combined recall and recognition deficits in a similarly injured group of patients (8) and animals (9, 10).Recognition is thought to rely on two processes: familiarity, wherein upon seeing a person's face, the rememberer has only a vague sense he has met the person before, and recollection, wherein the subject sees the person's face and vividly remembers details of the encounter (11,12). What role the hippocampus plays in supporting these processes remains the subject of considerable debate. Many memory researchers have proposed the discrepancy in the lesion data above derives from the fact that the hippocampus, which is well known to play a role in associative and relational memory (13), exclusively subserves recollection, whereas familiarity is supported by the extrahippocampal medial temporal lobe (MTL) (14). By this account, humans and animals are able to compensate for the loss of the hippocampus, and thus recollection, by relying on familiarity (15-18). A contrasting view holds that the hippocampus instead contributes to both recollection and familiarity, thus explaining why hippocampal damage is associated with severe impairment of both processes and consequently the overall recognition performance (4,8,19,20). Whether neural circuitry underlying familiarity and recollection lie within the hippocampus has also been extensively studied using functional MRI (fMRI) (21). Still, that many fMRI experiments show that ...

The authors found that indirect bypass does not promote adequate pial collateral artery development and appears to be of limited utility in patients with symptomatic ICA or MCA stenoocclusive disease and secondary hemodynamic failure. Rates of postoperative TIAs or cerebral infarctions after indirect bypass in this patient population do not differ from previous reports in patients who received medical management only.

This systematic review revealed no significant association between lamina terminalis fenestration and a reduced incidence of shunt-dependent hydrocephalus. The interpretation of these results, however, is restricted by unmatched cohort differences as well as other inherent study limitations. Although the overall literature supports lamina terminalis fenestration, a number of authors have questioned the technique's benefits, thus rendering its efficacy in reducing shunt-dependent hydrocephalus unclear. A well-designed, multicenter, randomized controlled trial is needed to definitively address the efficacy of this microsurgical technique.