Study identifies neuronal basis of impaired consciousness in 'absence' epilepsy - Yale School of Medicine

Imagine slipping successful and retired of consciousness hundreds of times per day, staying awake the full clip but having nary consciousness of consciousness during these lapses.

In children with lack epilepsy, these highly disruptive episodes are known arsenic lack seizures. Children acquisition little staring spells, during which they temporarily suffer consciousness. Absence seizures tin beryllium captured by abnormal rhythms connected EEG recordings, but their neuronal origin has ne'er earlier been identified.

Using a familial exemplary known arsenic Genetic Absence Epilepsy Rats of Strasbourg (GAERS), Yale researchers person identified the neuronal ground for this condition. Their findings were published Jan. 10 successful Nature Communications.

“First, we studied behaviour during seizures utilizing an auditory effect task, and a spontaneous motivated licking liquid reward task,” said elder writer Hal Blumenfeld, MD, PhD, the Mark Loughridge and Michele Williams Professor of Neurology and prof of neuroscience and neurosurgery astatine Yale School of Medicine. “Next, we imaged the rats utilizing functional magnetic resonance imaging [fMRI] to representation encephalon enactment during seizures. Finally, we recorded electrical signals from the encephalon utilizing EEG and electrical awesome from azygous neurons utilizing multi-contact silicon probes.”

The experiments were led by Cian McCafferty, who astatine the clip was a postdoctoral chap astatine Yale and is present a lecturer and main researcher astatine University College Cork. The squad observed that not lone bash the rats’ effect to outer stimuli mimic those of children with lack epilepsy, but the rats besides revealed 4 antithetic types of neuronal enactment during seizures.

“Most neurons showed sustained decreases successful enactment during seizures, explaining the decreased encephalon relation and the impaired consciousness seen during lack seizures successful some rats and children,” Blumenfeld said. “However, immoderate neurons showed sustained increases during seizures, immoderate showed transient increases astatine seizure onset only, and others showed nary change.”

Defining 4 types of neuronal enactment could effect successful much customized attraction for children with lack epilepsy, selectively targeting a definite benignant of neuron and causing less broadside effects.

Perhaps astir importantly, Blumenfeld said, the recordings of electrical encephalon signals from this survey could assistance epilepsy specialists forestall seizures successful the archetypal spot and dainty patients earlier their onset.

Having completed this first-of-its-kind survey with a rat model, Blumenfeld and his squad anticipation that children whose mundane lives are disrupted by losses of consciousness during lack epilepsy seizures volition beryllium capable to regain a consciousness of normalcy and instrumentality to the activities they enjoy.