TY - JOUR
T1 - Temporal lobe interictal spikes disrupt encoding and retrieval of verbal memory
T2 - A subregion analysis
AU - Camarillo-Rodriguez, Liliana
AU - Leenen, Iwin
AU - Waldman, Zachary
AU - Serruya, Mijail
AU - Wanda, Paul A.
AU - Herweg, Nora A.
AU - Kahana, Michael J.
AU - Rubinstein, Daniel
AU - Orosz, Iren
AU - Lega, Bradley
AU - Podkorytova, Irina
AU - Gross, Robert E.
AU - Worrell, Gregory
AU - Davis, Kathryn A.
AU - Jobst, Barbara C.
AU - Sheth, Sameer A.
AU - Weiss, Shennan A.
AU - Sperling, Michael R.
N1 - Publisher Copyright:
© 2022 International League Against Epilepsy.
PY - 2022/9
Y1 - 2022/9
N2 - Objective: The medial temporal lobe (MTL) encodes and recalls memories and can be a predominant site for interictal spikes (IS) in patients with focal epilepsy. It is unclear whether memory deficits are due to IS in the MTL producing a transient decline. Here, we investigated whether IS in the MTL subregions and lateral temporal cortex impact episodic memory encoding and recall. Methods: Seventy-eight participants undergoing presurgical evaluation for medically refractory focal epilepsy with depth electrodes placed in the temporal lobe participated in a verbal free recall task. IS were manually annotated during the pre-encoding, encoding, and recall epochs. We examined the effect of IS on word recall using mixed-effects logistic regression. Results: IS in the left hippocampus (odds ratio [OR] =.73, 95% confidence interval [CI] =.63–.84, p <.001) and left middle temporal gyrus (OR =.46, 95% CI =.27–.78, p <.05) during word encoding decreased subsequent recall performance. Within the left hippocampus, this effect was specific for area CA1 (OR =.76, 95% CI =.66–.88, p <.01) and dentate gyrus (OR =.74, 95% CI =.62–.89, p <.05). IS in other MTL subregions or inferior and superior temporal gyrus and IS occurring during the prestimulus window did not affect word encoding (p >.05). IS during retrieval in right hippocampal (OR =.22, 95% CI =.08–.63, p =.01) and parahippocampal regions (OR =.24, 95% CI =.07–.8, p <.05) reduced the probability of recalling a word. Significance: IS in medial and lateral temporal cortex contribute to transient memory decline during verbal episodic memory.
AB - Objective: The medial temporal lobe (MTL) encodes and recalls memories and can be a predominant site for interictal spikes (IS) in patients with focal epilepsy. It is unclear whether memory deficits are due to IS in the MTL producing a transient decline. Here, we investigated whether IS in the MTL subregions and lateral temporal cortex impact episodic memory encoding and recall. Methods: Seventy-eight participants undergoing presurgical evaluation for medically refractory focal epilepsy with depth electrodes placed in the temporal lobe participated in a verbal free recall task. IS were manually annotated during the pre-encoding, encoding, and recall epochs. We examined the effect of IS on word recall using mixed-effects logistic regression. Results: IS in the left hippocampus (odds ratio [OR] =.73, 95% confidence interval [CI] =.63–.84, p <.001) and left middle temporal gyrus (OR =.46, 95% CI =.27–.78, p <.05) during word encoding decreased subsequent recall performance. Within the left hippocampus, this effect was specific for area CA1 (OR =.76, 95% CI =.66–.88, p <.01) and dentate gyrus (OR =.74, 95% CI =.62–.89, p <.05). IS in other MTL subregions or inferior and superior temporal gyrus and IS occurring during the prestimulus window did not affect word encoding (p >.05). IS during retrieval in right hippocampal (OR =.22, 95% CI =.08–.63, p =.01) and parahippocampal regions (OR =.24, 95% CI =.07–.8, p <.05) reduced the probability of recalling a word. Significance: IS in medial and lateral temporal cortex contribute to transient memory decline during verbal episodic memory.
KW - CA1
KW - dentate gyrus
KW - episodic memory
KW - interictal epileptiform discharges
KW - intracranial EEG
KW - lateral temporal cortex
KW - medial temporal lobe
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U2 - 10.1111/epi.17334
DO - 10.1111/epi.17334
M3 - Article
C2 - 35708911
AN - SCOPUS:85132995231
SN - 0013-9580
VL - 63
SP - 2325
EP - 2337
JO - Epilepsia
JF - Epilepsia
IS - 9
ER -