Detail publikace

Effect Of Cognitive Stimulation On Hippocampal Ripples In Epileptic Patients

BRÁZDIL, M. CIMBÁLNÍK, J. ROMAN, R. HALÁMEK, J. JURÁK, P.

Originální název

Effect Of Cognitive Stimulation On Hippocampal Ripples In Epileptic Patients

Český název

Effect Of Cognitive Stimulation On Hippocampal Ripples In Epileptic Patients

Anglický název

Effect Of Cognitive Stimulation On Hippocampal Ripples In Epileptic Patients

Typ

článek ve sborníku

Jazyk

en

Originální abstrakt

Interictal HFOs (ripples and fast ripples) have been repeatedly identified in recordings from depth macroelectrodes in epileptics. In contrast to fast ripples, which are believed to reflect the neuronal substrates of epileptogenicity, ripples are considered to be a signature of both normal and epileptic brain processes. The differentiation of physiological and epileptic ripples in intracranial recordings remains unavailable. We analyzed SEEG recordings in seven patients with intractable partial seizures in whom hippocampal activity was recorded in resting state and subsequently during simple cognitive task with randomly presented frequent and rare visual stimuli. Using automated detection of ripples based on length of power envelope, we analyzed potentia l differences in ripple rate (RR) in the cognitive vs. resting period, within epileptic (EH) and nonepileptic hippocampi (NH). Further direct impact of cognitive stimuli on ripples (immediately after the stimulus) was investigated. Ripples have been detected within hippocampal recordings in all the investigated subjects. Mean RR in resting periods was 11.36 +/- 8.34/min within EH, and 10.13 +/- 8.75/min within NH. In the cognitive task periods mean RR within EH and NH decreased to 7.16 +/-5.75/min, and 8.75 +/- 7.69/min respectively. The reduction of RR during cognitive stimulation was significant in EH, but not in NH. Interestingly we observed a transient suppression of ripples in both EH (slight) and NH (significant) in the first second after the stimuli onset, followed by a significant increase in RR for both EH and NH. Our results point to different reactivity of ripples within EH and NH to the cognitive stimulation.

Český abstrakt

Interiktálních HFO (vlnky a rychlé vlnky) bylo opakovaně zjištěno v nahrávky z hloubky macroelectrodes v epileptiky. Na rozdíl od rychlé vlny, které jsou věřil, aby odrážely neuronální substráty epileptogenicity, vlnky považují za podpis obou normální a epileptickými mozkových procesů. Odlišení fyziologických a epileptické vlny v intrakraniální recordings zůstává k dispozici. Analyzovali jsme SEEG nahrávky v sedmi pacientů s nezvladatelnou parciálními záchvaty, kterým hipokampální aktivita byla zaznamenána v klidovém stavu a v následně během jednoduché kognitivní úkol s náhodně vykázaly časté a vzácné vizuální podněty. Pomocí automatické detekce vlnky na základě délky moc obálky, jsme analyzovali potentia l rozdíly v ceně zvlnění (RR) v kognitivní vs. klidové období, v rámci epilepsie (EH) a nonepileptic hipokampus (NH). Dále byla zkoumána přímý dopad kognitivní podnětů na vlnky (bezprostředně po stimulační). Vlnky byly zjištěny v rámci hipokampální nahrávky ve všech zkoumaných subjektů. 11,36 +/-8,34/min v rámci EH a 10.13 +/-8,75/min v rámci NH střední RR v klidové období. V období znamená kognitivní úkol RR v rámci EH a NH snížil 7.16 +/-5,75/min a 8,75 +/-7,69/min. Snížení RR během kognitivní stimulace byl významný v EH, ale ne v NH. Zajímavé je jsme pozorovali přechodné potlačování vlnění v EH (mírné) a NH (významné) v první vteřině po nástupu podněty, následuje výrazný posun v záznamu o prostředku pro EH a NH. Naše výsledky ukazují na různé reaktivita vlnky EH a NH na kognitivní stimulaci.

Anglický abstrakt

Interictal HFOs (ripples and fast ripples) have been repeatedly identified in recordings from depth macroelectrodes in epileptics. In contrast to fast ripples, which are believed to reflect the neuronal substrates of epileptogenicity, ripples are considered to be a signature of both normal and epileptic brain processes. The differentiation of physiological and epileptic ripples in intracranial recordings remains unavailable. We analyzed SEEG recordings in seven patients with intractable partial seizures in whom hippocampal activity was recorded in resting state and subsequently during simple cognitive task with randomly presented frequent and rare visual stimuli. Using automated detection of ripples based on length of power envelope, we analyzed potentia l differences in ripple rate (RR) in the cognitive vs. resting period, within epileptic (EH) and nonepileptic hippocampi (NH). Further direct impact of cognitive stimuli on ripples (immediately after the stimulus) was investigated. Ripples have been detected within hippocampal recordings in all the investigated subjects. Mean RR in resting periods was 11.36 +/- 8.34/min within EH, and 10.13 +/- 8.75/min within NH. In the cognitive task periods mean RR within EH and NH decreased to 7.16 +/-5.75/min, and 8.75 +/- 7.69/min respectively. The reduction of RR during cognitive stimulation was significant in EH, but not in NH. Interestingly we observed a transient suppression of ripples in both EH (slight) and NH (significant) in the first second after the stimuli onset, followed by a significant increase in RR for both EH and NH. Our results point to different reactivity of ripples within EH and NH to the cognitive stimulation.

Klíčová slova

Kognitivní stimulace, hipokampus, epilepsie

Rok RIV

2013

Vydáno

23.06.2013

Strany od

1

Strany do

1

Strany počet

1

BibTex


@inproceedings{BUT101505,
  author="Milan {Brázdil} and Jan {Cimbálník} and Robert {Roman} and Josef {Halámek} and Pavel {Jurák}",
  title="Effect Of Cognitive Stimulation On Hippocampal Ripples In Epileptic Patients",
  annote="Interictal HFOs (ripples and fast ripples) have been repeatedly identified in recordings from depth macroelectrodes in epileptics. In contrast to fast ripples, which are believed to reflect the neuronal substrates of epileptogenicity, ripples are considered to be a signature of both normal and epileptic brain processes. The differentiation of physiological and epileptic ripples in intracranial recordings remains unavailable. We analyzed SEEG recordings in seven patients with intractable partial seizures in whom hippocampal activity was recorded in resting state and subsequently during simple cognitive task with randomly presented frequent and rare visual stimuli. Using automated detection of ripples based on length of power envelope, we analyzed potentia l differences in ripple rate (RR) in the cognitive vs. resting period, within epileptic (EH) and nonepileptic hippocampi (NH). Further direct impact of cognitive stimuli on ripples (immediately after the stimulus) was investigated. Ripples have been detected within hippocampal recordings in all the investigated subjects. Mean RR in resting periods was 11.36 +/- 8.34/min within EH, and 10.13 +/- 8.75/min within NH. In the cognitive task periods mean RR within EH and NH decreased to 7.16 +/-5.75/min, and 8.75 +/- 7.69/min respectively. The reduction of RR during cognitive stimulation was significant in EH, but not in NH. Interestingly we observed a transient suppression of ripples in both EH (slight) and NH (significant) in the first second after the stimuli onset, followed by a significant increase in RR for both EH and NH. Our results point to different reactivity of ripples within EH and NH to the cognitive stimulation.",
  booktitle="Epilepsia",
  chapter="101505",
  doi="10.1016/j.jns.2013.07.131",
  howpublished="online",
  number="1",
  year="2013",
  month="june",
  pages="1--1",
  type="conference paper"
}