Biology subjects

Tefera, E.

Publications and source records attributed to Tefera, E..

3 recordsLinked to original sources

bioRxiv2026

Spoken Recall Reveals Lexical and Mnemonic Function Differences in Temporal Lobe Epilepsy Patients

Background and Objectives: Word-finding difficulty is common in healthy aging and in neurologic disorders, including temporal lobe epilepsy (TLE) and early Alzheimer disease. Standard language measures have limited sensitivity for detecting subtle or longitudinal changes in spontaneous speech. We examined whether natural language processing and acoustic analysis of spoken biographical recall could identify lexical and temporal speech features associated with language and memory performance in TLE. Methods: We conducted a cross-sectional observational study of spoken recall during a Famous Faces biographical memory task. Adults with TLE and healthy controls (HCs) viewed 20 famous faces and spontaneously recalled biographical details. Speech was transcribed and diarized using automated tools. Lexical measures included word counts and lexical index (ratio of rare to common words). Acoustic measures included utterance and pause duration and pause frequency. Features were compared between groups and correlated with neuropsychological measures, including Montreal Cognitive Assessment (MoCA), Boston Naming Test (BNT), delayed recall, education, and biographical recall accuracy Results: Eighty-one adults participated (51 TLE, 30 HCs). Lexical measures did not differ between groups. In TLE, lexical index correlated with BNT performance (rs=0.62) and MoCA score (rs=0.35). Compared with HCs, participants with TLE produced shorter utterances (5.54 {+/-} 2.50 vs. 6.59 {+/-} 2.63; Cohen's d=0.41, 95% CI -0.05 to 0.86, p=0.041), shorter pauses (0.61 {+/-} 0.21 vs 0.67 {+/-} 0.22, Cohen's d=0.29, 95% CI -0.16 to 0.74, p=0.043), and more frequent pauses (10.81 {+/-} 3.30 vs 9.29 {+/-} 3.59, Cohen's d=-0.45, 95% CI -0.90 to 0.01, p=0.036). Higher education was associated with longer utterances, longer pauses, and lower pause frequency, without evidence of a diagnosis-by-education interaction. Faster utterance rate was associated with better biographical recall in both groups, while higher pause rate was associated with worse recall in TLE. Discussion: Speech-derived lexical and temporal features from naturalistic recall capture clinically relevant variation in language and memory-related performance. Although lexical output did not distinguish TLE from HCs, lexical richness tracked naming and global cognition in TLE, while temporal speech features related to recall performance. These findings support the potential of automated speech analysis as a digital behavioral biomarker for word-finding difficulty in neurologic populations.

neuroscience↗

bioRxiv2026

Film Recall Reveals Intact Event Memory but Impaired Sequence Memory in Temporal Lobe Epilepsy Patients

BACKGROUND AND OBJECTIVESPatients with epilepsy (PWE), especially temporal lobe epilepsy (TLE), experience impaired memory for personally experienced events. However, current assessments of episodic memory are limited in their ecological validity with a potential to miss detection of subtle cognitive decline. We conducted an exploratory study to determine whether a naturalistic film-viewing task with open-ended spoken recall could detect memory differences between TLE patients and healthy controls (HCs). METHODSTLE patients (ages 18-60, fluent in English, not legally blind) were recruited from a Level 4 Epilepsy Center (2018-2024). TLE diagnosis was based on seizure semiology, MRI Brain, and EEG. TLE patients scored [≥]22/30 on the Montreal Cognitive Assessment (MOCA); HCs scored [≥]26/30. Subjects watched 6 short films and then freely recalled film details. Spoken responses were recorded, transcribed, segmented, and scored for film- and event-level recall. Recall order was assessed using the Damerau-Levenshtein distance. Semantic and causal centrality were quantified using sentence embeddings and rater-identified causal links, respectively. Beta regression with cluster-robust standard errors assessed group and centrality effects on recall probability. Beta regression evaluated the influence of age, MOCA, and testing platform on sequence recall error. RESULTSWe recruited 51 subjects (27 TLEs; 24 HCs, 70.1% F, mean 29.9 {+/-}8.3 years). TLE patients and HCs showed similar recall of films (HC 89% {+/-}11% vs TLE 88% {+/-}18%, p = 0.54), coarse events (HC 50% {+/-}16% vs TLE 44% {+/-}18%, p = 0.19) and fine events (HC 25%{+/-}10% vs. TLE 22%{+/-}12%, p=0.17). Both groups recalled high causal centrality events better. For coarse event sequence recall, TLE patients showed a numerical trend toward greater sequence errors compared to HCs (HC 10.8% {+/-} 10.5% vs. TLE 19.5% {+/-} 18%, p = 0.06), although this difference did not reach statistical significance. However, TLE patients showed significantly greater fine event sequence errors at recall than HCs (HC 15% {+/-}13% vs 23% {+/-}18%, p = 0.02, Hedges g = 0.85, Cliffs {delta} = 0.51), with RTLE demonstrating more sequence errors than HCs (15%{+/-}13 vs. 29%{+/-}21% p = 0.021) Age, education, MOCA, and performance on standard verbal and visual memory tasks were unrelated to film, event, and sequence recall performance. DISCUSSIONWe demonstrate that a short film task with spontaneous spoken recall can identify sequence memory impairment in TLE patients despite intact film- and event-level recall. Sequence memory may represent a subtle manifestation of memory impairment that is not detected by standard cognitive testing. Key PointsO_LIWe asked whether a naturalistic film recall task could detect episodic memory impairment in a temporal lobe epilepsy cohort. C_LIO_LIPatients with temporal lobe epilepsy showed comparable film and event recall compared to healthy controls but were found to have impaired sequence memory. C_LIO_LISequential memory for temporal order is an overlooked aspect of episodic memory that may detect subtle memory decline. C_LI

neuroscience↗

bioRxiv2024

Natural Language Processing Applied to Spontaneous Recall of Famous Faces Reveals Memory Dysfunction in Temporal Lobe Epilepsy Patients

Objective and BackgroundEpilepsy patients rank memory problems as their most significant cognitive comorbidity. Current clinical assessments are laborious to administer and score and may not always detect subtle memory decline. The Famous Faces Task (FF) has robustly demonstrated that left temporal lobe epilepsy (LTLE) patients remember fewer names and biographical details compared to right TLE (RTLE) patients and healthy controls (HCs). We adapted the FF task to capture subjects entire spontaneous spoken recall, then scored responses using manual and natural language processing (NLP) methods. We expected to replicate previous group level differences using spontaneous speech and semi-automated analysis. MethodsSeventy-three (N=73) adults (28 LTLE, 18 RTLE, and 27 HCs) were included in a case-control prospective study design. Twenty FF in politics, sports, and entertainment (active 2008-2017) were shown to subjects, who were asked if they could recognize and spontaneously recall as much biographical detail as possible. We created human-generated and automatically-generated keyword dictionaries for each celebrity, based on a randomly selected training set of half of the HC transcripts. To control for speech output, we measured the speech duration, total word count and content word count for the FF task and a Cookie Theft Control Task (CTT), in which subjects were merely asked to describe a visual scene. Subjects responses to FF and CTT tasks were recorded, transcribed, and analyzed in a blinded manner with a combination of manual and automated NLP approaches. ResultsFamous face recognition accuracy was similar between groups. LTLE patients recalled fewer biographical details compared to HCs and RTLEs using both the gold-standard human-generated dictionary (24%{+/-}12% vs. 31%{+/-}12% and 30%{+/-}12%, p=0.007) and the automated dictionary (24%{+/-}12% vs. 31%{+/-}12% and 32%{+/-}13%, p=0.007). There were no group level differences in speech duration, total word count, or content word count for either the FF and CTT to explain difference in recall performance. There was a positive, statistically significant relationship between MOCA score and FF recall performance as scored by the human-generated ({rho}= .327, p= .029) and automatically-generated dictionaries ({rho}= .422, p= .004) for TLE subjects, but not HCs, an effect that was driven by LTLE subjects. DiscussionLTLE patients remember fewer details of famous people than HCs or RTLE patients, as discovered by NLP analysis of spontaneous recall. Decreased biographical memory was not due to decreased speech output and correlated with lower MOCA scores. NLP analysis of spontaneous recall can detect memory dysfunction in clinical populations in a semi-automated, objective, and sensitive manner.

neuroscience↗