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Background: Listening to heartbeat sounds have been found to affect cardiac activity and behavior. However, less is known about the effects of these stimuli on brain activity and cognition. Alpha oscillations (8-13 Hz) are considered markers of cortical activation. Frontal alpha Asymmetry (FαA) reflects the valence attributed to the stimulus and the tendency to approach/avoid it., Aim: This study investigates the effects of sounds mimicking heart pulsations at different rhythms on reaction times and neurophysiological activity., Method: EEG data were collected during a resting-state condition and two Simple Reaction Time tasks (SRT), during which artificially generated heartbeat sounds at fast (120 bpm, FastBeat condition) or slow (60 bpm, SlowBeat condition) rhythms were administered. Alpha power was compared across the three conditions. Differences in the SRT and FαA values were examined between the FastBeat and SlowBeat conditions., Results: Compared to the resting-state condition, decreased alpha activity over bilateral frontocentral regions was observed in both tasks. The comparison between the FastBeat and the SlowBeat conditions revealed faster response times, a pattern of alpha suppression over right frontal regions, and lower FαA values in the former., Conclusions: The similarity of alpha reductions elicited in the comparison between the resting-state and the two task conditions suggests that these patterns were ascribable to processes common to both conditions (SRT task, auditory stimulation). In contrast, the differences between the two conditions suggest that fast heartbeat sounds are perceived as more adverse and stressful stimuli, inducing cortical activation over regions associated with negative states and avoidant tendencies., Competing Interests: Declaration of competing interest None., (Copyright © 2024. Published by Elsevier B.V.)

Objectives: To assess the prognostic role of evoked potentials (EP) in neonates with normal magnetic resonance imaging (MRI) after therapeutic hypothermia (TH) for hypoxic-ischemic encephalopathy (HIE)., Methods: Thirty-five neonates recruited for TH because of HIE, having normal neonatal MRI, performed neonatal somatosensory (SEP), visual (VEP) evoked potentials and electroencephalogram (EEG). The effect of SEP, VEP or EEG abnormalities on Griffith's developmental scales at 12 and 24 months was measured; positive (PPV) and negative (NPV) predictive value, sensitivity, specificity and accuracy were calculated., Results: At 24 months, 28% had global psychomotor impairment and 57% had isolated impairments. VEP abnormality was associated with impaired hearing-language score (p = 0.002) and performance score (p < 0.0001). VEP achieved best PPV (0.91, 95% C.I. 0.62-0.99) and specificity (0.93, 95% C.I. 0.70-0.99). The combination of neurophysiological tests achieved the best NPV (0.85, 95% C.I. 0.58-0.96), sensitivity (0.90, 95% C.I. 0.70-0.97), overall accuracy (0.83, 95% C.I. 0.67-0.92)., Conclusions: Psychomotor sequelae may occur in survivors of neonatal HIE with normal MRI. VEP is the single best neurophysiological prognostic marker but the combination of neurophysiological tests has a better value., Significance: When facing the challenge of neurodevelopmental prognosis in infants with normal MRI after TH, EPs are useful prognostic tools, complementary to EEG., (Copyright © 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Objective: The introduction of therapeutic hypothermia for neonatal hypoxic-ischemic encephalopathy calls for reevaluation of the prognostic role of somatosensory evoked potentials (SEPs)., Methods: Among 80 consecutive neonates undergoing hypothermia for hypoxic-ischemic encephalopathy, 58 performed SEPs and MRI at 4-14 days of life and were recruited in this multicenter study. SEPs were scored as: 0 (bilaterally/unilaterally recorded N20) or 1 (bilaterally absent N20). The severity of brain injury was scored using MRI., Results: Bilaterally absent N20 was observed in 10/58 neonates (17%); all had moderate/severe MRI abnormalities; 36/48 neonates (75%) with score 0 at SEPs had normal MRI. The positive predictive value of SEPs on MRI outcome was of 1.00, while the negative predictive value 0.72, sensitivity 0.48, specificity 1.00, with an accuracy of 0.78 (p < .001)., Conclusions: Bilateral absence of cortical SEPs predicts moderate/severe MRI pattern of injury., Significance: Therapeutic hypothermia does not seem to significantly affect prognostic reliability of SEPs., (Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Objective: To evaluate whether wearing a wool cap, a routine practice used to prevent heat loss in premature infants, affects interpretation of electroencephalogram spectral analysis., Methods: Eighteen premature infants (median gestational age 28 weeks, range 23-32) without neurological complications were randomized to two channel (C3, C4 referred to Cz) digital electroencephalogram recordings with (90 min) and without (90 min) wearing wool cap, at 4 days of life. Electroencephalogram was analyzed automatically by measurement of burst suppression ratio and asymmetry index and by Fast Fourier Transform to calculate total absolute spectral power; relative spectral power in the δ (0.5-3.5 Hz), θ (4-7.5 Hz), α (8-12.5 Hz), and β (13-30 Hz) frequency bands; spectral edge frequency; and mean dominant frequency., Results: The use of wool cap had no effect on all electroencephalogram parameters considered. Gestational age showed an effect on relative spectral power of all considered bands, spectral edge frequency and mean dominant frequency, while no effect was seen on burst suppression ratio and asymmetry index. Neonates born at gestational weeks lower than 28 had significantly higher relative power in the δ band and lower relative power in the α and β bands., Conclusions: Heat loss prevention using wool cap does not affect interpretation of spectral electroencephalogram. Spectral values in our group of very premature infants without neurological complications correspond to normal data reported in the literature. Maturation changes consist of reduction of relative power of the δ band, spectral edge frequency and mean dominant frequency., (Copyright © 2014 Elsevier Masson SAS. All rights reserved.)