Journal of neurology
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The pathophysiology of human narcolepsy is still poorly understood. The hypoactivity of some neurotransmitter systems has been hypothesised on the basis of the canine model. To determine whether narcolepsy is associated with changes in excitability of the cerebral cortex, we assessed the excitability of the motor cortex with transcranial magnetic stimulation (TMS) in 13 patients with narcolepsy and in 12 control subjects. ⋯ These results are consistent with an impaired balance between excitatory and inhibitory intracortical circuits in narcolepsy that leads to cortical hypoexcitability. We hypothesise that the deficiency of the excitatory hypocretin/orexin-neurotransmitter-system in narcolepsy is reflected in changes of cortical excitability since circuits originating in the lateral hypothalamus and in the basal forebrain project widely to the neocortex, including motor cortex. This abnormal excitability of cortical networks could be the physiological correlate of excessive daytime sleepiness and it could be the substrate for allowing dissociated states of wakefulness and sleep to emerge suddenly while patients are awake, which constitute the symptoms of narcolepsy.
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The significance of deja vu is widely recognised in the context of temporal lobe epilepsy, and enquiry about deja vu is frequently made in the clinical assessment of patients with possible epilepsy. Deja vu has also been associated with several psychiatric disorders. The historical context of current understanding of deja vu is discussed. ⋯ Several neuroanatomical and psychological models of the deja vu experience are highlighted, implicating the perceptual, mnemonic and affective regions of the lateral temporal cortex, hippocampus and amygdala in the genesis of deja vu. A possible genetic basis for a neurochemical model of deja vu is discussed. Clinical approaches to the patient presenting with possible deja vu are proposed.
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Journal of neurology · Dec 2004
Long-term prognosis of ischemic stroke in young adults. Study of 272 cases.
There have been few studies of the long-term prognosis of young adults with ischemic stroke. The present study aimed to evaluate the long-term clinical outcome in a large series of young adults with ischemic stroke admitted to a tertiary medical center over the last 27 years, and to identify possible predictors for mortality, stroke recurrence and poor functional recovery. ⋯ The long-term prognosis for the ischemic stroke in the young is better than in the elderly, but the risk of mortality in young adults with ischemic stroke is much higher than in the general population of the same age. A bad prognosis is associated with an atherosclerotic risk profile, with a higher mortality and recurrent stroke rates and poorer functional recovery. The main functional limitation in the young survivors of their initial ischemic stroke occurs in work activity, since most patients are independent but almost half of them do not return to work.
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Journal of neurology · Oct 2004
Randomized Controlled Trial Comparative Study Clinical TrialA placebo-controlled trial of gabapentin for painful HIV-associated sensory neuropathies.
Painful HIV-associated sensory neuropathies (HIV-SN) are a common complication of HIV infection. The pathogenesis is unknown and the treatment very limited. Gabapentin (GBP) is effective in painful diabetic neuropathy and postherpetic neuralgia and its effectiveness on painful HIV-SN has been reported anecdotally. ⋯ GBP was more effective than placebo in reducing pain and sleep interference in patients with HIV-SN.