102. Maturation of the auditory evoked potentials: its relation with temporal properties of acoustic stimuli

ABSTRACTThe plainfin midshipman, Porichthys notatus, is a soniferous marine teleost fish that generates acoustic signals for intraspecific social communication. Nocturnally active males and females rely on their auditory sense to detect and locate vocally active conspecifics during social behaviors. Previous work showed that the midshipman inner ear saccule and lagena are highly adapted to detect and encode socially relevant acoustic stimuli, but the auditory sensitivity and function of the midshipman utricle remain largely unknown. Here, we characterized the auditory evoked potentials from hair cells in the utricle of non-reproductive type I males and tested the hypothesis that the midshipman utricle is sensitive to behaviorally relevant acoustic stimuli. Hair cell potentials were recorded from the rostral, medial and caudal regions of the utricle in response to pure tone stimuli presented by an underwater speaker. We show that the utricle is highly sensitive to particle motion stimuli produced by an underwater speaker positioned in the horizontal plane. Utricular potentials were recorded across a broad range of frequencies with lowest particle acceleration (dB re. 1 m s−2) thresholds occurring at 105 Hz (lowest frequency tested; mean threshold −32 dB re. 1 m s−2) and highest thresholds at 605–1005 Hz (mean threshold range −5 to −4 dB re. 1 m s−2). The high gain and broadband frequency sensitivity of the utricle suggest that it likely serves a primary auditory function and is well suited to detect conspecific vocalizations including broadband agonistic signals and the multiharmonic advertisement calls produced by reproductive type I males.

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Effect of the Use of Different Acoustic Stimuli on Cortical Auditory Evoked Potentials and Autonomic Cardiac Modulation

BioMed Research International ◽

10.1155/2018/5171304 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9

Author(s):

Simone Fiuza Regaçone ◽

Vitor Engrácia Valenti ◽

Ana Cláudia Figueiredo Frizzo

Keyword(s):

Nervous System ◽

Evoked Potentials ◽

Auditory Evoked Potentials ◽

Parasympathetic Nervous System ◽

Acoustic Stimulation ◽

Acoustic Stimuli ◽

Complex Stimuli ◽

Cortical Auditory Evoked Potentials ◽

The Relationship ◽

Cardiac Modulation

Purpose. The aim of this study was to analyze the relationship between Cortical Auditory Evoked Potentials (CAEPs) measurements and autonomic cardiac modulation in relation to different acoustic stimuli and to verify which of these stimuli have more influence on the autonomic nervous system. Methods. Sixty healthy women, aged between 18 and 25 years, participated in this study. Prior to the CAEP examination, blood pressure and resting heart rate were measured using a stethoscope, sphygmomanometer, and the Polar RS800CX cardiofrequency measures. After the collection of these measures, the CAEP test was started simultaneously with the HRV collection. Results. All the HRV indices presented correlations with the components of the CAEPs. During the acoustic stimulation, a predominance of the modulation of the autonomic parasympathetic nervous system was observed. The harmonic and disharmonic stimuli were the ones that presented the most correlations between the measures analyzed in this study. Conclusions. There was an association between CAEP and cardiac autonomic modulation in relation to different acoustic stimuli. Among the acoustic stimuli used in this study, the ones that most influenced the autonomic cardiac modulation were harmonic and disharmonic stimuli, which are acoustically more complex stimuli.

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