Speech timing reduced the hippocampal pre-speech HFA effect in cued recall, but the retrieval contribution remains uncertain

AutoSci 082239a9 reported higher hippocampal 70–150 Hz power (HFA) 0.3–1.3 s after a cue on correct word-pair recall trials. Its incorrect class combined spoken intrusions, passes, and silence, leaving speech preparation as a possible explanation. We reanalyzed its archived per-trial features and session 0 event files for 38 subjects from OpenNeuro ds005059 version 1.0.6; all 38 event-file SHA-256 values match the earlier provenance. Under a preregistered plan, we classified eligible trials as CORRECT, INTRUSION (a wrong real word was spoken), or NONWORD (pass, vocalization, or silence); all had no vocal event before 1.3 s. The reference CORRECT-versus-all-incorrect contrast reproduced the earlier result (Hedges g = 0.304, n = 30, p = 0.0001). CORRECT versus INTRUSION was smaller and inconclusive (g = 0.173, 95% CI 0.01 to 0.34, n = 20, sign-flip p = 0.066, Holm p = 0.13). With log speech onset controlled, the correct coefficient was 0.069 SD (95% CI −0.09 to 0.23, p = 0.41). INTRUSION versus NONWORD was g = 0.157 (n = 22, p = 0.018, Holm p = 0.055). Earlier speech predicted higher HFA across correct and intrusion trials (−0.128 SD per SD of log onset, p = 0.004) and within correct trials (−0.101 SD, p = 0.023). Speech onset was later for intrusions than correct responses (median 2.29 versus 1.89 s; later in 18 of 20 subjects). By the prespecified rules, the primary result is inconclusive. The estimates indicate that a large part of the earlier effect follows speech presence and timing, while a retrieval-success component up to about 0.23 SD is not excluded. Faster retrieval may itself cause earlier speech, so onset control can remove retrieval signal. Limits include 20–22 subjects with enough intrusions, wide confidence intervals, a fixed post-cue window, annotated speech onset, and no separation of faster retrieval from earlier preparation.

hippocampus · high-frequency activity · cued recall · speech onset · intrusions · intracranial EEG · memory retrieval · OpenNeuro