Try a new search

Format these results:

Searched for:

person:friedd06

in-biosketch:true

Total Results:

183


Vascular risk factors as predictors of epilepsy in older age: The Framingham Heart Study

Stefanidou, Maria; Himali, Jayandra J; Devinsky, Orrin; Romero, Jose R; Ikram, Mohammad Arfan; Beiser, Alexa S; Seshadri, Sudha; Friedman, Daniel
OBJECTIVE:Stroke is the most common cause of epilepsy in older age. Subclinical cerebrovascular disease is believed to underlie some of the 30%-50% of late-onset epilepsy without a known cause (Li et al. Epilepsia. 1997;38:1216; Cleary et al. Lancet. 2004;363:1184). We studied the role of modifiable vascular risk factors in predicting subsequent epilepsy among participants ages 45 or older in the Framingham Heart Study (FHS), a longitudinal, community-based study. METHODS:Participants of the Offspring Cohort who attended FHS exam 5 (1991-1995) were included who were at least 45-years-old at that time, had available vascular risk factor data, and epilepsy follow-up (n = 2986, mean age 58, 48% male). Adjudication of epilepsy cases included review of medical charts to exclude seizure mimics and acute symptomatic seizures. The vascular risk factors studied included hypertension, diabetes mellitus, smoking, and hyperlipidemia. The role of the Framingham Stroke Risk Profile score was also investigated. Cox proportional hazards regression models were used for the analyses. RESULTS:Fifty-five incident epilepsy cases were identified during a mean of 19 years of follow-up. Hypertension was associated with a near 2-fold risk (hazard ratio [HR]: 1.93, 95% confidence interval [CI]: 1.10-3.37, p = .022) of developing epilepsy, even after adjustment for prevalent and interim stroke. In secondary analysis, excluding patients with normal blood pressure who were receiving anti-HTN (anti-hypertensive) treatment (n = 2613, 50 incident epilepsy cases) the association was (HR: 2.44, 95% CI: 1.36-4.35, p = .003). SIGNIFICANCE/CONCLUSIONS:Our results offer further evidence that hypertension, a potentially modifiable and highly prevalent vascular risk factor in the general population, increases 2- to 2.5-fold the risk of developing late-onset epilepsy.
PMID: 34786697
ISSN: 1528-1167
CID: 5049142

Depression and suicidality among Hispanics with epilepsy: Findings from the Managing Epilepsy Well (MEW) Network integrated database

O'Kula, Susanna S; Briggs, Farren B S; Brownrigg, Brittany; Sarna, Kaylee; Rosales, Omar; Shegog, Ross; Fraser, Robert T; Johnson, Erica K; Quarells, Rakale C; Friedman, Daniel; Sajatovic, Martha; Spruill, Tanya M
OBJECTIVE:Network. METHODS:to examine the prevalence of elevated depressive symptoms (PHQ ≥ 10, NDDI-E ≥ 15) and suicidal ideation (PHQ-9 item 9 ≥ 1, NDDI-E item 4 ≥ 2). Multilevel mixed-effects logistic regression models examined associations between ethnicity, elevated depressive symptoms, and suicidal ideation among PWE. Secondary analyses examined correlates of elevated depressive symptoms and suicidal ideation among Hispanic PWE. RESULTS:Of 559 participants, 49.6% (n = 277) were Hispanic. Elevated depressive symptoms were endorsed by 38.1% (n = 213) of all participants (32.5% of Hispanics); suicidal ideation was endorsed by 18.4% (n = 103) of all participants (16.3% of Hispanics). After adjustment for sociodemographic and health attributes, Hispanic PWE had a 44% lower prevalence of elevated depressive symptoms (OR = 0.56, CI 0.37-0.84, p = 0.0056) compared to non-Hispanics but similar rates of suicidal ideation (OR = 0.84, CI 0.45-1.58, p = 0.59). Acculturation measures were available for 256 (92.4%) of Hispanic PWE: language preference was Spanish for 62.9%, 46.1% were foreign-born. Spanish-speaking Hispanics were less likely than English-speaking Hispanics to report elevated depressive symptoms (OR = 0.43, CI 0.19-0.97, p = 0.041); however, Hispanics who reported fair or poor health status had a four-fold higher depression prevalence compared to those who reported excellent or very good health status [reference group] (OR = 4.44, CI 1.50-13.18, p = 0.0071). Of the Hispanics who provided prior 30-day seizure data, ≥1 monthly seizure was independently associated with higher depression prevalence (OR = 3.11, CI 1.29-7.45, p = 0.01). Being foreign-born was not associated with elevated depressive symptoms or suicidal ideation prevalence. CONCLUSIONS:In a large, geographically diverse sample of PWE, elevated depressive symptoms were significantly lower in Hispanics compared to non-Hispanics. Spanish language preference was associated with a lower prevalence of elevated depressive symptoms among Hispanic PWE. Future studies should include acculturation data to better screen for depression and suicidal ideation risk and optimize interventions for Hispanic PWE.
PMID: 34798558
ISSN: 1525-5069
CID: 5049762

Long-term priors influence visual perception through recruitment of long-range feedback

Hardstone, Richard; Zhu, Michael; Flinker, Adeen; Melloni, Lucia; Devore, Sasha; Friedman, Daniel; Dugan, Patricia; Doyle, Werner K; Devinsky, Orrin; He, Biyu J
Perception results from the interplay of sensory input and prior knowledge. Despite behavioral evidence that long-term priors powerfully shape perception, the neural mechanisms underlying these interactions remain poorly understood. We obtained direct cortical recordings in neurosurgical patients as they viewed ambiguous images that elicit constant perceptual switching. We observe top-down influences from the temporal to occipital cortex, during the preferred percept that is congruent with the long-term prior. By contrast, stronger feedforward drive is observed during the non-preferred percept, consistent with a prediction error signal. A computational model based on hierarchical predictive coding and attractor networks reproduces all key experimental findings. These results suggest a pattern of large-scale information flow change underlying long-term priors' influence on perception and provide constraints on theories about long-term priors' influence on perception.
PMID: 34725348
ISSN: 2041-1723
CID: 5037932

Moment-by-moment tracking of naturalistic learning and its underlying hippocampo-cortical interactions

Michelmann, Sebastian; Price, Amy R; Aubrey, Bobbi; Strauss, Camilla K; Doyle, Werner K; Friedman, Daniel; Dugan, Patricia C; Devinsky, Orrin; Devore, Sasha; Flinker, Adeen; Hasson, Uri; Norman, Kenneth A
Humans form lasting memories of stimuli that were only encountered once. This naturally occurs when listening to a story, however it remains unclear how and when memories are stored and retrieved during story-listening. Here, we first confirm in behavioral experiments that participants can learn about the structure of a story after a single exposure and are able to recall upcoming words when the story is presented again. We then track mnemonic information in high frequency activity (70-200 Hz) as patients undergoing electrocorticographic recordings listen twice to the same story. We demonstrate predictive recall of upcoming information through neural responses in auditory processing regions. This neural measure correlates with behavioral measures of event segmentation and learning. Event boundaries are linked to information flow from cortex to hippocampus. When listening for a second time, information flow from hippocampus to cortex precedes moments of predictive recall. These results provide insight on a fine-grained temporal scale into how episodic memory encoding and retrieval work under naturalistic conditions.
PMID: 34518520
ISSN: 2041-1723
CID: 5012282

Effects of hippocampal interictal discharge timing, duration, and spatial extent on list learning

Leeman-Markowski, Beth; Hardstone, Richard; Lohnas, Lynn; Cowen, Benjamin; Davachi, Lila; Doyle, Werner; Dugan, Patricia; Friedman, Daniel; Liu, Anli; Melloni, Lucia; Selesnick, Ivan; Wang, Binhuan; Meador, Kimford; Devinsky, Orrin
Interictal epileptiform discharges (IEDs) can impair memory. The properties of IEDs most detrimental to memory, however, are undefined. We studied the impact of temporal and spatial characteristics of IEDs on list learning. Subjects completed a memory task during intracranial EEG recordings including hippocampal depth and temporal neocortical subdural electrodes. Subjects viewed a series of objects, and after a distracting task, recalled the objects from the list. The impacts of IED presence, duration, and propagation to neocortex during encoding of individual stimuli were assessed. The effects of IED total number and duration during maintenance and recall periods on delayed recall performance were also determined. The influence of IEDs during recall was further investigated by comparing the likelihood of IEDs preceding correctly recalled items vs. periods of no verbal response. Across 6 subjects, we analyzed 28 hippocampal and 139 lateral temporal contacts. Recall performance was poor, with a median of 17.2% correct responses (range 10.4-21.9%). Interictal epileptiform discharges during encoding, maintenance, and recall did not significantly impact task performance, and there was no significant difference between the likelihood of IEDs during correct recall vs. periods of no response. No significant effects of discharge duration during encoding, maintenance, or recall were observed. Interictal epileptiform discharges with spread to lateral temporal cortex during encoding did not adversely impact recall. A post hoc analysis refining model assumptions indicated a negative impact of IED count during the maintenance period, but otherwise confirmed the above results. Our findings suggest no major effect of hippocampal IEDs on list learning, but study limitations, such as baseline hippocampal dysfunction, should be considered. The impact of IEDs during the maintenance period may be a focus of future research.
PMID: 34416521
ISSN: 1525-5069
CID: 4988992

Telephone-based depression self-management in Hispanic adults with epilepsy: a pilot randomized controlled trial

Spruill, Tanya M; Friedman, Daniel; Diaz, Laura; Butler, Mark J; Goldfeld, Keith S; O'Kula, Susanna; Montesdeoca, Jacqueline; Payano, Leydi; Shallcross, Amanda J; Kaur, Kiranjot; Tau, Michael; Vazquez, Blanca; Jongeling, Amy; Ogedegbe, Gbenga; Devinsky, Orrin
Depression is associated with adverse outcomes in epilepsy but is undertreated in this population. Project UPLIFT, a telephone-based depression self-management program, was developed for adults with epilepsy and has been shown to reduce depressive symptoms in English-speaking patients. There remains an unmet need for accessible mental health programs for Hispanic adults with epilepsy. The purpose of this study was to evaluate the feasibility, acceptability, and effects on depressive symptoms of a culturally adapted version of UPLIFT for the Hispanic community. Hispanic patients with elevated depressive symptoms (n = 72) were enrolled from epilepsy clinics in New York City and randomized to UPLIFT or usual care. UPLIFT was delivered in English or Spanish to small groups in eight weekly telephone sessions. Feasibility was assessed by recruitment, retention, and adherence rates and acceptability was assessed by self-reported satisfaction with the intervention. Depressive symptoms (PHQ-9 scores) were compared between study arms over 12 months. The mean age was 43.3±11.3, 71% of participants were female and 67% were primary Spanish speakers. Recruitment (76% consent rate) and retention rates (86-93%) were high. UPLIFT participants completed a median of six out of eight sessions and satisfaction ratings were high, but rates of long-term practice were low. Rates of clinically significant depressive symptoms (PHQ-9 ≥5) were lower in UPLIFT versus usual care throughout follow-up (63% vs. 72%, 8 weeks; 40% vs. 70%, 6 months; 47% vs. 70%, 12 months). Multivariable-adjusted regressions demonstrated statistically significant differences at 6 months (OR = 0.24, 95% CI, 0.06-0.93), which were slightly reduced at 12 months (OR = 0.30, 95% CI, 0.08-1.16). Results suggest that UPLIFT is feasible and acceptable among Hispanic adults with epilepsy and demonstrate promising effects on depressive symptoms. Larger trials in geographically diverse samples are warranted.
PMID: 33963873
ISSN: 1613-9860
CID: 4866912

Spatiotemporal dynamics between interictal epileptiform discharges and ripples during associative memory processing

Henin, Simon; Shankar, Anita; Borges, Helen; Flinker, Adeen; Doyle, Werner; Friedman, Daniel; Devinsky, Orrin; Buzsáki, György; Liu, Anli
We describe the spatiotemporal course of cortical high-gamma activity, hippocampal ripple activity and interictal epileptiform discharges during an associative memory task in 15 epilepsy patients undergoing invasive EEG. Successful encoding trials manifested significantly greater high-gamma activity in hippocampus and frontal regions. Successful cued recall trials manifested sustained high-gamma activity in hippocampus compared to failed responses. Hippocampal ripple rates were greater during successful encoding and retrieval trials. Interictal epileptiform discharges during encoding were associated with 15% decreased odds of remembering in hippocampus (95% confidence interval 6-23%). Hippocampal interictal epileptiform discharges during retrieval predicted 25% decreased odds of remembering (15-33%). Odds of remembering were reduced by 25-52% if interictal epileptiform discharges occurred during the 500-2000-ms window of encoding or by 41% during retrieval. During encoding and retrieval, hippocampal interictal epileptiform discharges were followed by a transient decrease in ripple rate. We hypothesize that interictal epileptiform discharges impair associative memory in a regionally and temporally specific manner by decreasing physiological hippocampal ripples necessary for effective encoding and recall. Because dynamic memory impairment arises from pathological interictal epileptiform discharge events competing with physiological ripples, interictal epileptiform discharges represent a promising therapeutic target for memory remediation in patients with epilepsy.
PMID: 33889945
ISSN: 1460-2156
CID: 4847522

Flexible, high-resolution thin-film electrodes for human and animal neural research

Chiang, Chia-Han; Wang, Charles; Barth, Katrina; Rahimpour, Shervin; Trumpis, Michael; Duraivel, Suseendrakumar; Rachinskiy, Iakov; Dubey, Agrita; Wingel, Katie Elizabeth; Wong, Megan; Witham, Nicholas Steven; Odell, Thomas George; Woods, Virginia; Bent, Brinnae; Doyle, Werner; Friedman, Daniel; Bihler, Eckardt; Reiche, Christopher Friedrich; Southwell, Derek; Haglund, Michael M; Friedman, Allan H; Lad, Shivanand; Devore, Sasha; Devinsky, Orrin; Solzbacher, Florian; Pesaran, Bijan; Cogan, Gregory; Viventi, Jonathan
OBJECTIVE:Brain functions such as perception, motor control, learning, and memory arise from the coordinated activity of neuronal assemblies distributed across multiple brain regions. While major progress has been made in understanding the function of individual neurons, circuit interactions remain poorly understood. A fundamental obstacle to deciphering circuit interactions is the limited availability of research tools to observe and manipulate the activity of large, distributed neuronal populations in humans. Here we describe the development, validation, and dissemination of flexible, high-resolution, thin-film (TF) electrodes for recording neural activity in animals and humans. APPROACH/METHODS:We leveraged standard flexible printed-circuit manufacturing processes to build high-resolution TF electrode arrays. We used biocompatible materials to form the substrate (liquid crystal polymer; LCP), metals (Au, PtIr, and Pd), molding (medical-grade silicone), and 3D-printed housing (nylon). We designed a custom, miniaturized, digitizing headstage to reduce the number of cables required to connect to the acquisition system and reduce the distance between the electrodes and the amplifiers. A custom mechanical system enabled the electrodes and headstages to be pre-assembled prior to sterilization, minimizing the setup time required in the operating room. PtIr electrode coatings lowered impedance and enabled stimulation. High-volume, commercial manufacturing enables cost-effective production of LCP-TF electrodes in large quantities. MAIN RESULTS/RESULTS:Our LCP-TF arrays achieve 25× higher electrode density, 20× higher channel count, and 11× reduced stiffness than conventional clinical electrodes. We validated our LCP-TF electrodes in multiple human intraoperative recording sessions and have disseminated this technology to >10 research groups. Using these arrays, we have observed high-frequency neural activity with sub-millimeter resolution. SIGNIFICANCE/CONCLUSIONS:Our LCP-TF electrodes will advance human neuroscience research and improve clinical care by enabling broad access to transformative, high-resolution electrode arrays.
PMID: 34010815
ISSN: 1741-2552
CID: 4877332

SUDEP education among U.S. and international neurology trainees

Nascimento, Fábio A; Laze, Juliana; Friedman, Daniel; Lam, Alice; Devinsky, Orrin
We evaluated baseline sudden unexpected death in epilepsy (SUDEP) knowledge and counseling practices among national and international adult neurology trainees with a 12-question online survey. The survey was emailed to all 169 U.S. neurology residency program directors and select international neurology/epilepsy program leaders. Program leaders were asked to distribute the survey link to adult neurology trainees. There were 161 respondents in the U.S. and 171 respondents outside the U.S. The latter were from 25 Latin American, European, Asian, and African countries. More than 90% of all trainees reported familiarity with SUDEP definition. Familiarity with SUDEP risk factors and mitigation measures ranged from 56% to 67% across these groups, with international trainees slightly more familiar with risk factors (67% vs. 61% in U.S.) but less familiar with mitigation measures (56% vs. 63% in U.S.). Approximately half of national (49%) and international (54%) trainees rarely or never counseled patients on SUDEP. Less than half of national (44%) and international (41%) trainees were educated about SUDEP. Many U.S. and adult neurology trainees remain unfamiliar with SUDEP risk factors and mitigation measures. Sudden unexpected death in epilepsy counseling falls below recommended standards. We suggest that worldwide neurology training programs' leaderships consider improving SUDEP education targeted at adult neurology trainees.
PMID: 34111766
ISSN: 1525-5069
CID: 4900212

Proteomics and Transcriptomics of the Hippocampus and Cortex in SUDEP and High-Risk SUDEP Patients

Leitner, Dominique F; Mills, James D; Pires, Geoffrey; Faustin, Arline; Drummond, Eleanor; Kanshin, Evgeny; Nayak, Shruti; Askenazi, Manor; Verducci, Chloe; Chen, Bei Jun; Janitz, Michael; Anink, Jasper J; Baayen, Johannes C; Idema, Sander; van Vliet, Erwin A; Devore, Sasha; Friedman, Daniel; Diehl, Beate; Scott, Catherine; Thijs, Roland; Wisniewski, Thomas; Ueberheide, Beatrix; Thom, Maria; Aronica, Eleonora; Devinsky, Orrin
OBJECTIVE:To identify the molecular signaling pathways underlying sudden unexpected death in epilepsy (SUDEP) and high-risk SUDEP compared to epilepsy control patients. METHODS:For proteomics analyses, we evaluated the hippocampus and frontal cortex from microdissected post-mortem brain tissue of 12 SUDEP and 14 non-SUDEP epilepsy patients. For transcriptomics analyses, we evaluated hippocampus and temporal cortex surgical brain tissue from mesial temporal lobe epilepsy (MTLE) patients: 6 low-risk and 8 high-risk SUDEP as determined by a short (< 50 seconds) or prolonged (≥ 50 seconds) postictal generalized EEG suppression (PGES) that may indicate severely depressed brain activity impairing respiration, arousal, and protective reflexes. RESULTS:In autopsy hippocampus and cortex, we observed no proteomic differences between SUDEP and non-SUDEP epilepsy patients, contrasting with our previously reported robust differences between epilepsy and non-epilepsy control patients. Transcriptomics in hippocampus and cortex from surgical epilepsy patients segregated by PGES identified 55 differentially expressed genes (37 protein-coding, 15 lncRNAs, three pending) in hippocampus. CONCLUSION/CONCLUSIONS:The SUDEP proteome and high-risk SUDEP transcriptome were similar to other epilepsy patients in hippocampus and frontal cortex, consistent with diverse epilepsy syndromes and comorbidities associated with SUDEP. Studies with larger cohorts and different epilepsy syndromes, as well as additional anatomic regions may identify molecular mechanisms of SUDEP.
PMID: 33910938
ISSN: 1526-632x
CID: 4852152