Publications by authors named "Aaron Sheerin"

Experimental animals' seizures are often defined arbitrarily based on duration, which may lead to misjudgement of the syndrome and failure to develop a cure. We employed a functional definition of seizures based on the clinical practice of observing epileptiform electrocorticography and simultaneous ictal behaviour, and examined post-traumatic epilepsy induced in rats by rostral parasagittal fluid percussion injury and epilepsy patients evaluated with invasive monitoring. We showed previously that rostral parasagittal fluid percussion injury induces different types of chronic recurrent spontaneous partial seizures that worsen in frequency and duration over the months post injury.

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Ion channelopathy plays an important role in human epilepsy with a genetic cause and has been hypothesized to occur in epilepsy after acquired insults to the CNS as well. Acquired alterations of ion channel function occur after induction of status epilepticus (SE) in animal models of epilepsy, but it is unclear how they correlate with the onset of spontaneous seizures. We examined the properties of hyperpolarization-activated cation (HCN) channels in CA1 hippocampal pyramidal neurons in conjunction with video-EEG (VEEG) recordings to monitor the development of spontaneous seizures in the rat pilocarpine model of epilepsy.

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The mechanisms underlying brain seizure tolerance, a phenomenon in which brief periods of seizures protect brain against the lethal effects of subsequent sustained seizures, are poorly understood. Because brain seizure tolerance and brain ischemia tolerance likely share certain common mechanisms, the recent evidence that activation of extracellular regulated kinase (ERK) and p38 kinase pathways plays a critical role in ischemic preconditioning suggests that a similar mechanism may underlie brain seizure tolerance. We investigated the hypothesis in a rat kainic acid preparation of seizure preconditioning and tolerance, which was established by induction of one episode of priming epileptic status lasting for 20 min on the first day and another episode of sustained epileptic status lasting for 2 hr on the second day.

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Purpose: The purpose of this study was to determine whether N-palmitoylethanolamide (PEA), a putative endocannabinoid, would be effective against kindled amygdaloid seizures. For a comparison with earlier work, we also tested the effectiveness of PEA against pentylenetetrazol (PTZ)-induced convulsions.

Methods: Kindling electrodes were implanted bilaterally in the amygdala in 32 Long-Evans rats.

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Febrile convulsions are common among preschool children and are studied experimentally with hyperthermia in rat pups. Although heat-induced convulsions (HC+) can affect behaviors in adulthood, to date no one has examined the effects on behavior in the neonatal period. We examined the effects of HC+ on ultrasonic vocalizations (USVs) and mother-pup interactions in P10- and P12-aged rat pups.

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Unilateral forced nostril breathing (UFNB) through the left nostril is associated with enhanced spatial abilities, whereas UFNB through the right nostril is associated with enhanced verbal abilities. However, the effects of UFNB on standard tasks of laterality (e.g.

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In this study we examined the unknown issue of whether seizure-induced newborn hippocampal neurons in freely moving adult rats are able to respond to pathophysiological stimuli in the same way as their neighboring neurons do. Three days after pentylenetrazol (PTZ)-induced generalized seizures, rats received 5-bromodeoxyuridine (BrdU) injections to label dividing cells, followed 4 weeks later by the second PTZ injection to induce second episode of generalized seizures. We observed that the first episode of PTZ-induced seizures resulted in a significant increase in the number of newborn neurons in the adult hippocampal dentate gyrus.

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Previous research has indicated that normals exhibit strong leftward biases during free-viewing perceptual judgments of brightness and quantity. When participants view two symmetrical objects and they are forced to choose which object appears darker or more numerous, participants usually select the stimulus with the relevant feature on the left side. The present study investigated the possibility that these perceptual asymmetries are dependent on scanning a stimulus horizontally across the midline by administering a task with two rectangular reversed stimuli presented either horizontally or vertically.

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