This Month in Archives of Neurology

In this basic science review, Kabbaj describes what is known about the circuitry of the hypothalamus, midbrain, amygdala, prefrontal cortex, hippocampus, and limbic areas that determines how an individual will perceive stress and cope with it. Are differences among individual responses genetic, conditioned, or both?

The frequent occurrence of the IgG antibody to ganglioside GQ1b in Miller Fisher syndrome and related anti-GQ1b–positive syndromes is of great diagnostic and therapeutic significance to physicians. The pathophysiologic role and clinical relevance of these ganglioside antibodies are elegantly reviewed by Paparounas.

In this review on conscious awareness, Ortinski and Meador address 3 general questions: Where in the brain does consciousness occur? When does it occur in relation to external and/or internal stimuli? How are the underlying neural mechanisms involved in the emergence of consciousness? The integration of several essential nodes of consciousness into 1 seamless hologram of thought and awareness—the binding problem—poses many new questions. The neuronal correlates of consciousness introduced by Crick and Koch are advanced. It is a timely and stimulating discussion of perhaps the central issue in neuroscience: why we are aware.

Rainier and colleagues report the identification of missense mutations in the myofibrillogenesis regulator gene (MR-1) in affected subjects in 2 unrelated kindreds with paroxysmal dystonia choreoathetosis (PDC), which maps to chromosome 2q33-2q35. They show that the MR-1 exon containing these mutations (exon 1) is expressed only in the brain, explaining the brain-specific symptoms of subjects with these mutations. Furthermore, they show that these mutations are absent in control subjects and cause substitutions of valine for alanine at amino acid positions 6 (PDC-Pa kindred) and 9 (PDC-Det kindred). Although MR-1 function is unknown, they suggest that PDC pathophysiologic features involve abnormal ion localization, similar to how ion channel disturbance has been described in other episodic neurologic disorders. It is an important new genetic finding and a tribute to the brilliant and dedicated research that John Fink, MD, and his colleagues have pursued for many years regarding the genetic basis of movement disorders. Roger N. Rosenberg, MD, Editor, provides editorial perspective.

Levy et al, in a careful and well-designed study, find a lack of familial aggregation in Parkinson and Alzheimer diseases. These findings do not support the hypothesis of a major shared genetic contribution to the etiology of the 2 most common neurodegenerative disorders. Editorial comment is provided by Walter A. Kukull, PhD.

The comparison of initial treatment with pramipexole vs levodopa in early Parkinson disease (PD) is reported by the Parkinson Study Group. Each therapy as an initial treatment for PD, as described in this article, has selective benefits and adverse effects. Both options resulted in a similar quality of life. Although both are reasonable forms of initial dopaminergic therapy for PD, they are associated with different efficacy and adverse effect profiles.

Kumar et al report the occurrence of 3 clusters of Parkinson disease in Canada. They conclude that in light of current evidence, an important role for the environmental causation of Parkinson disease is present in these clusters, including viral infection and toxins.

This article by Schlegel and colleagues studied whether the National Institutes of Health Stroke Scale (NIHSS) predicted disposition in patients with stroke who were treated with thrombolysis. They found that an increasing NIHSS score was a robust and independent predictor of discharge to rehabilitation or nursing facilities, roughly doubling for each 5-point increment. Intracerebral hemorrhage after thrombolysis therapy is a catastrophic event that often precludes discharge home.

The number needed to treat is a useful measure of a treatment's clinical benefit or harm. Saver reports that for every 100 patients with acute stroke treated with thrombolytic therapy, about 32 have a better final outcome and 3 have a worse final outcome as a result of treatment. A quantitative assessment of the number needed to treat, as reviewed in this article, establishes the definitive value of neurotherapeutic intervention.

Joo et al define the clinical, electroencephalographic, magnetic resonance imaging, Wada test, and neuropsychological test results in patients who had unitemporal or bitemporal hypometabolism with mesial temporal lobe epilepsy who werestudied using positron emission tomography. These findings are of considerable value in evaluating patients for temporal lobectomy.

Oh and colleagues found that the corpus callosum (CC) was a more sensitive location for depicting axonal injury than other regions of normal-appearing white matter in patients with multiple sclerosis. A correlation between the reduction of N-acetylaspartate–creatine-phosphocreatine in the normal-appearing CC and T1 lesions suggests that the transaction of axons in lesions may cause distant axonal damage and/or dysfunction that are expressed and more sensitively detectable in the CC.

The utility and prognostic importance of digital video-electroencephalographic monitoring in the neurological-neurosurgical intensive care unit (NICU) is discussed by Pandian and colleagues. In general, continuous electroencephalographic monitoring is essential in the diagnosis and treatment of refractory status epilepticus or encephalopathy with seizures in the NICU.

The expression and activation of nuclear factor κB (NF-kB) in nerve biopsy specimens from patients with peripheral neuropathies of different origins are reported by Mazzeo and colleagues. Nuclear factor κB is a transcription factor expressed in many cells and is involved in immune and inflammatory responses. Nerve biopsy specimens from patients with neuropathies of several important types were studied for the activated form of NF-kB. Their findings indicate a direct role of NF-kB in inflammatory neuropathies and familial amyloidotic polyneuropathy.

The Frontal Assessment Battery is presented to differentiate between frontotemporal dementia and Alzheimer disease. The findings of Slachevsky et al show that the Frontal Assessment Battery can distinguish patients with frontotemporal dementia from those who have Alzheimer disease with a sensitivity of 77% and a specificity of 87%.