Auditory steady-state responses to tones amplitude-modulated at 80–110 Hz

Abstract

Steady-state responses can be recorded from the human scalp in response to tones that are sinusoidally modulated in amplitude at rates between 60 and 120 Hz. For 60 dB SPL 1000-Hz tones the maximum baseline-to-peak amplitude of about 0.06 microV occurs for modulation rates between 80 and 95 Hz. The phase of the response does not change with modulation depths greater than 25% and the amplitude saturates at modulation depths greater than 50%. The presence or absence of a response can be accurately determined by frequency-domain statistics and the response becomes clearly recognizable at intensities that are 16 +/- 8 dB above behavioral thresholds. With increasing intensity the response increases in amplitude at 1.9 nV/dB until an intensity of 70 dB SPL. As the intensity increases above 70 dB SPL the response increases in amplitude more rapidly at 7.8 nV/dB (at 1000 Hz) and contains significant energy at harmonics of the modulation frequency. This second stage of the intensity function is more prominent for stimuli with lower carrier frequencies (500 more than 1000 more than 2000 Hz) and is attenuated by high-pass masking. These steady-state responses should be helpful in evaluating human auditory physiology and in objective audiometry.

Electrically Evoked Auditory Steady-State Responses in a Guinea Pig Model: Latency Estimates and Effects of Stimulus Parameters

“…Table 1 shows latency estimates derived from modulation transfer functions that have been reported in the literature as well as the results obtained in this study. Amplitude and latency estimates of the ESSR obtained in the present study are, in general, consistent with those reported for acoustic stimulation [Stapells et al, 1984[Stapells et al, , 1987Kuwada et al, 1986Kuwada et al, , 2002Picton et al, 1987;Cohen et al, 1991;Dolphin and Mountain, 1992;Lins et al, 1995;John and Picton, 2000;John et al, 2001;Purcell et al, 2003Purcell et al, , 2004. Specifically, modulation transfer functions obtained from the above-mentioned studies all exhibit larger response amplitudes at two different modulation frequency regions: the lower frequency region at approximately 40 Hz and the higher frequency region at approximately 80-100 Hz.…”

“…Data obtained from the present study showed maximum response amplitudes at the higher modulation frequency region (around 95 Hz). This finding is in contrast to results from humans [Stapells et al, 1984[Stapells et al, , 1987Kuwada et al, 1986Kuwada et al, , 2002Picton et al, 1987;Cohen et al, 1991;Lins et al, 1995;John and Picton, 2000;John et al, 2001;Picton et al, 2003;Purcell et al, 2003Purcell et al, , 2004 showing steadystate responses recorded using the low modulation frequencies to be larger than those recorded using the high modulation frequencies. However, this may reflect the fact that our results were obtained from sedated animals and as such the response amplitudes at the lower modulation frequencies may be decreased because they are more sensitive to sleep and sedation.…”

Latencies of Auditory Steady-State Responses Recorded in Early Infancy

“…This may be related to the fact that generators further along the auditory pathway are less sensitive to more rapid stimuli. For the 80-to 125-Hz region, adult latencies of 13-30 ms have been reported for amplitude-modulated and/or frequency-modulated tones [Cohen et al, 1991;John et al, 2001;John and Picton, 2000a;Lins et al, 1995;Purcell et al, 2003; for review see Picton et al, 2003]. The large range of latency values in this region can be explained by the variety of tested carrier frequencies and the different intensities of the stimuli.…”

Correlação do potencial evocado auditivo de estado estável com outros achados em audiologia pediátrica

“…Sugere-se a profundidade de modulação em amplitude aplicada ao estímulo superior a 50% (Lins et al, 1995;Lins et al, 2002).…”

“…Outras vantagens da aplicação do PEAEE são a interpretação e análise dos resultados, que não dependem da experiência do avaliador, como ocorre com os potenciais com estímulos transientes (Lins, et al, 1995 (Lins et al, 1996;Aoyagi et al, 1999;Perez-abalo et al, 2001;Lins, 2002;Swanepoell et al, 2004;Calil, 2006;Luts et al, 2006;Duarte, 2008;Rodrigues, 2009). …”