Long-term effect of prednisolone on functional blink recovery after transient peripheral facial motor paralysis.

Objective: To determine the functional recovery in patients with severe transient peripheral facial motor paralysis (Bell palsy).

Study Design: Prospective controlled trial.

Setting: Academic medical center.

Anti-malaria drug mefloquine induces motor learning deficits in humans.

Mefloquine (a marketed anti-malaria drug) prophylaxis has a high risk of causing adverse events. Interestingly, animal studies have shown that mefloquine imposes a major deficit in motor learning skills by affecting the connexin 36 gap junctions of the inferior olive. We were therefore interested in assessing whether mefloquine might induce similar effects in humans.

Long-term changes in cerebellar activation during functional recovery from transient peripheral motor paralysis.

Localized altered cerebellar cortical activity can be associated with short-term changes in motor learning that take place in the course of hours, but it is unknown whether it can be correlated to long-term recovery from transient peripheral motor diseases, and if so, whether it occurs concomitantly in related brain regions. Here we show in a longitudinal fMRI study of patients with unilateral Bell's palsy that increases in ipsilateral cerebellar activity follow the recovery course of facial motor functions over at least one and a half years. These findings hold true for changes in brain activity related to both oral and peri-orbital activation, even though these processes are differentially mediated by unilateral and bilateral brain connectivities, respectively.

Savings and extinction of conditioned eyeblink responses in fragile X syndrome.

The fragile X syndrome (FRAXA) is the most widespread heritable form of mental retardation caused by the lack of expression of the fragile X mental retardation protein (FMRP). This lack has been related to deficits in cerebellum-mediated acquisition of conditioned eyelid responses in individuals with FRAXA. In the present behavioral study, long-term effects of deficiency of FMRP were investigated by examining the acquisition, savings and extinction of delay eyeblink conditioning in male individuals with FRAXA.

Are locus coeruleus neurons involved in blinking?

To investigate the involvement of the noradrenergic locus coeruleus (LC) in the reflex blink circuit, c-Fos and neuronal tracer experiments were performed in the rat. LC neurons involved in reflex blink were localized by analyzing c-Fos protein expression after electrical stimulation of the supraorbital nerve. Subsequently, neuronal tracers were injected in two different nuclei which are part of the reflex blink circuit.