Recent literature has provided new insights into the role of rehabilitation in neurological recovery post-stroke. The present review combines results of animal and clinical research to provide a summary of published information regarding the mechanisms of neural recovery and impact of rehabilitation.

Plasticity of the uninjured and post-stroke brain is examined to provide a background for the examination of brain reorganization and recovery following stroke.

Recent research has confirmed many of the basic underpinnings of rehabilitation and provided new insight into the role of rehabilitation in neurological recovery. Recovery post stroke is dependent upon cortical reorganization, and therefore, upon the presence of intact cortex, especially in areas adjacent to the infarct. Exposure to stimulating and complex environments and involvement in tasks or activities that are meaningful to the individual with stroke serves to increase cortical reorganization and enhance functional recovery. Additional factors associated with neurological recovery include size of stroke lesion, and the timing and intensity of therapy.

Although randomized controlled trials (RCTs) are the gold standard for evaluating therapeutic interventions, surgical RCTs are particularly challenging and few have been done in the field of epilepsy surgery. We assess the level of RCT activity in epilepsy surgery and propose feasible alternatives to develop sustainable research initiatives in this area.

We undertook a systematic review of the world literature to assess the level of RCT activity in epilepsy surgery. Previous personal experience with RCTs in epilepsy surgery and examples of successful Canadian multicentre research networks were reviewed to propose initiatives for sustainable, valid research in epilepsy surgery.

We identified 12 RCTs in epilepsy surgery, including 692 patients, of whom 416 were involved in vagus nerve stimulation, 16 in various brain electrostimulation procedures, 180 in comparisons of different surgical techniques, and 80 in a comparison of medical versus surgical therapy. Most studies were of short duration (median = 3 months, range 3-12 months). In the area of resective surgery, only temporal lobe epilepsy has been subjected to any type of RCT comparison. All RCTs have been done within the last 13 years. There were no multicentre Canadian surgical studies.

The adoption of RCTs in epilepsy surgery has been slow and difficult worldwide. Because of its universal health care system and its well established epilepsy surgery centres, Canada is in a strong position to create a national epilepsy surgery research initiative capable of undertaking high quality, sustainable research in epilepsy surgery.

Saccadic adaptation corrects errors in saccadic amplitude. Experimentally-induced saccadic adaptation provides a method for studying motor learning. The cerebellum is a major participant in saccadic adaptation. Chiari type II malformation (CII) is a developmental deformity of the cerebellum and brainstem that is associated with spina bifida. We investigated the effects of CII on saccadic adaptation.

We measured eye movements using an infrared eye tracker in 21 subjects with CII (CII group) and 39 typically developing children (control group), aged 8-19 years. Saccadic adaptation was induced experimentally using targets that stepped horizontally 12º to the right and then stepped backward 3º during saccades.

Saccadic adaptation was achieved at the end of the adaptation phase in participants in each group. Saccadic amplitude gain decreased by 6.9% in the CII group and 9.3% in the control group. The groups did not differ significantly (p = 0.27). Amplitude gain reduction was significantly less in the CII participants who had multiple shunt revisions. Regression analyses revealed no effects of spinal lesion level, presence of nystagmus, or cerebellar vermis dysmorphology on saccadic adaptation.

The neural circuits involved in saccadic adaptation appear to be functionally intact in CII.

Middle-latency somatosensory evoked potentials (SEPs) following median nerve stimulation can provide a sensitive measure of cortical function. We sought to determine whether the mechanical forces of whiplash injury or concussion alter normal processing of middle-latency SEPs.

In a cross-sectional pilot study 20 subjects with whiplash were investigated (50% between 0.5-2 months and 50% between 6-41 months post injury) and compared to 83 healthy subjects using a standard middle-latency SEP procedure. In a subsequent prospective study subjects with either acute whiplash (n=13) or Grade 3 concussion (n=16) were investigated within 48 hours and again three months post injury.

In the pilot study the middle-latency SEP component N60 was significantly increased in the ten subjects investigated within two months after whiplash. In contrast, the ten subjects examined more than six months after injury showed normal latencies. In the prospective study N60 latencies were increased after whiplash and concussion when tested within 48 hours of injury. At three months, latencies were improved though still significantly different from controls post whiplash and concussion.

Both whiplash injury and concussion alter processing of the middle-latency SEP component N60 in the acute post traumatic period. The acute changes appear to normalize between three-six months post injury. The SEP similarities suggest that the overlapping clinical symptomatology post whiplash and concussion may reflect a similar underlying mechanism of rotational mild traumatic brain injury.

Behcet's disease is a multisystemic vascular inflammatory disorder of unknown origin. It is relatively rare and central nervous system involvement is seen in 5% of affected individuals. Somatosensory evoked potentials (SEPs) can provide information that shows the presence of clinically unsuspected lesions in the central nervous system of these patients. However, the effects of changing the stimulus frequencies on latencies of SEP potentials and central conduction time (CCT) in patients with neuro-Behcet's disease (NB) have not been studied yet. In this study, our aim was to reveal these effects to investigate whether the change of stimulus frequencies could be of convenient use in obtaining more accurate CCT estimations in SEP studies of these patients.

We performed median nerve SEPs of 14 patients with NB and 15 healthy volunteers. We changed the stimulus frequency: 2 Hz, 4Hz, 6Hz and 9Hz in successive recordings and statistically compared the changes on SEP potentials and peak and onset CCT in the neuro-Behcet (NB) group and the normal group.

Our results indicated that the onset CCT values of the NB group were higher than the normal group at 4Hz and 9Hz stimulations. However, the comparison of peak CCT in the NB group and the normal group did not show any statistically meaningful differences at all stimulation frequencies.

Onset CCT has not been measured before in former SEP studies of patients with NB. We highly recommend measuring onset CCT at higher stimulation frequencies in order to reveal central conduction time pathologies in these patients.

Neurofibromatosis type 2 (NF2) is an autosomal dominant disease predisposing individuals to the risk of developing tumors of cranial and spinal nerves. The NF2 tumor suppressor protein, known as Merlin/Schwanomin, is a member of the protein 4.1 superfamily that function as links between the cytoskeleton and the plasma membrane.

Upon selective extraction of membrane-associated proteins from erythrocyte plasma membrane (ghosts) using low ionic strength solution, the bulk of NF2 protein remains associated with the spectrin-actin depleted inside-out-vesicles. Western blot analysis showed a ~70 kDa polypeptide in the erythrocyte plasma membrane. Furthermore, quantitative removal of NF2 protein from the inside-out-vesicles was achieved using 1.0 M potassium iodide, a treatment known to remove tightly-bound peripheral membrane proteins.

These results suggest a novel mode of NF2 protein association with the erythrocyte membrane that is distinct from the known membrane interactions of protein 4.1. Based on these biochemical properties, several purification strategies were devised to isolate native NF2 protein from human erythrocyte ghosts. Using purified and recombinant NF2 protein as internal standards, we quantified approximately ~41-65,000 molecules of NF2 protein per erythrocyte.

We provide evidence for the presence of NF2 protein in the human erythrocyte membrane. The identification of NF2 protein in the human erythrocyte membrane will make it feasible to discover novel interactions of NF2 protein utilizing powerful techniques of erythrocyte biochemistry and genetics in mammalian cells.

Susac syndrome is a rare condition involving the brain, retina, and cochlea. Electroencephalogram (EEG) findings from published case reports show mainly generalized slowing.

A 30-year-old man presented with acute onset of superior vision loss, unsteady gait, and hearing loss. This was accompanied by short-term memory loss and behavioral and mood changes. MRI showed multiple white matter hyperintensities. The EEG showed frontal intermittent rhythmic delta activity. A diagnosis of Susac syndrome was made and treatment with methylprednisolone, ASA, and Nimodipine was instituted. At one-year follow-up, bilateral hearing loss, mild visual impairment, and mood changes were still apparent.

Frontal intermittent rhythmic delta activity can be seen in Susac syndrome.

Patients infected with West Nile virus (WNV) may develop acute neurologic disease, which can be severe or even fatal, including WNV meningitis, encephalitis, and an irreversible acute flaccid paralysis or poliomyelitis-like syndrome. Movement disorders have also been described.

We report combined neuronal loss, gliosis, and neurofibrillary tangle formation in the substantia nigra of a 41-year-old man with a history of WNV encephalomyelitis and poliomyelitis-like paralysis.

Clinically our patient did not display parkinsonism, however, it is interesting to speculate whether, in the absence of the residual subacute poliomyelitis-like syndrome, the neuropathologic findings could have eventually evolved clinically into WNV-associated postencephalitic parkinsonism.

SUNCT is a rare primary headache disorder that is associated with activation of the posterior hypothalamus and often poorly responsive to medication. Recently, a relationship between between pituitary microadenoma and SUNCT has been suggested, and reports of both amelioration and exacerbation by dopamine-agonists have been published. These findings suggest a functional role for the hypothalamic-pituitary axis in SUNCT.

We report the long-term 4 year follow-up of a 35 year-old patient with a 14-year history of medically and surgically intractable SUNCT who experienced immediate and complete resolution of symptoms after resection of a 6 mm pituitary microadenoma.

This patient was first seen at the age of 28 years with a 10-year history of attacks of right retro-orbital pain satisfying the IHS criteria for SUNCT. Many medical and surgical treatments were attempted without success. An MRI demonstrated a 6 mm microadenoma without compression of surrounding structures. A trial of bromocriptine caused marked exacerbation of his pain. The patient underwent a trans-sphenoidal resection of the pituitary lesion. SUNCT attacks worsened for the first 24h post-operatively, then disappeared. He has been completely headache-free, without medication, for the past 43 months with the last follow-up being January 2006.

This case emphasizes the relationship between pituitary microadenomas and SUNCT, supports the role of the hypothalamic-pituitary axis in the genesis of SUNCT, and illustrates the importance of careful imaging of the pituitary region in patients with SUNCT.