22 kHz and 55 kHz ultrasonic vocalizations differentially influence neural and behavioral outcomes: Implications for modeling anxiety via auditory stimuli in the rat

Abstract

The communicative role of ultrasonic vocalizations (USVs) in rats is well established, with distinct USVs indicative of different affective states. USVs in the 22kHz range are typically emitted by adult rats when in anxiety-or fear-provoking situations (e.g. predator odor, social defeat), while 55kHz range USVs are typically emitted in appetitive situations (e.g., play, anticipation of reward). Previous work indicates that USVs (real-time and playback) can effectively communicate these affective states and influence changes in behavior and neural activity of the receiver. Changes in cFos activation following 22kHz USVs have been seen in cortical and limbic regions involved in anxiety, including the basolateral amygdala (BLA). However, it is unclear how USV playback influences cFos activity within the bed nucleus of the stria terminalis (BNST), a region also thought to be critical in processing anxiety-related information, and the nucleus accumbens, a region associated with reward. The present work sought to characterize distinct behavioral, physiological, and neural responses in rats presented with aversive (22kHz) compared to appetitive (55kHz) USVs or silence. Our findings show that rats exposed to 22kHz USVs: 1) engage in anxiety-like behaviors in the elevated zero maze, and 2) show distinct patterns of cFos activation within the BLA and BNST that contrast those seen in 55kHz playback and silence. Specifically, 22kHz USVs increased cFos density in the anterodorsal nuclei, while 55kHz playback increased cFos in the oval nucleus of the BNST, without significant changes within the nucleus accumbens. These results provide important groundwork for leveraging ethologically-relevant stimuli in the rat to improve our understanding of anxiety-related responses in both typical and pathological populations.

Suppression of ovarian hormones in adolescent rats has no effect on anxiety‐like behaviour or c‐fos activation in the amygdala

“…Although these data suggest that Antide‐treated females might differ slightly from control females on some measures of responsiveness to novelty and fear‐inducing stimuli, this interpretation of the results was not supported by the underlying brain activity because no differences in c‐Fos labelling were evident between groups in the basolateral or medial amygdaloid nuclei. This lack of between‐group differences in c‐Fos measures was unexpected, given the sensitivity of the BLA to stressors, including aversive acoustic noises 89 . A potential explanation is that measures of immobilisation in the ASR task do not strongly reflect aversive responses, and future studies could benefit from employing startle amplitude measures instead.…”

Playback of Alarm and Appetitive Calls Differentially Impacts Vocal, Heart-Rate, and Motor Response in Rats

“…We observed a striking difference in HR levels following 50-kHz versus 22-kHz playback, which lasted for almost 3 min ( Figure 4 F; Table S16 C). To the best of our knowledge, HR changes following rats' exposure to different USV were not described before despite some attempts ( Demaestri et al., 2019 ).…”

“…Previous playback studies have shown that presenting 50-kHz USV evoked various behaviors such as approach ( Wohr and Schwarting, 2007 ), positive responses to ambiguous cues ( Saito et al., 2016 ), reduction in fights ( Kisko et al., 2015a ), restoration of sexual activity in devocalized rats ( White and Barfield, 1989 ), and awakening from haloperidol-induced catalepsy ( Tonelli et al., 2018 ). Whereas, exposing rats to 22-kHz playback inhibited behavior ( Wohr and Schwarting, 2007 ), decreased locomotor activity during replay and immediately afterward ( Sales, 1991 ; Brudzynski and Chiu, 1995 ), and caused negative responses to ambiguous cues ( Saito et al., 2016 ), and anxiety-like behaviors ( Demaestri et al., 2019 ). Presentation of 50-kHz versus 22-kHz playback also resulted in activation of c-Fos in different brain areas ( Beckett et al., 1997 ; Sadananda et al., 2008 ; Ouda et al., 2016 ; Demaestri et al., 2019 ).…”

“…Whereas, exposing rats to 22-kHz playback inhibited behavior ( Wohr and Schwarting, 2007 ), decreased locomotor activity during replay and immediately afterward ( Sales, 1991 ; Brudzynski and Chiu, 1995 ), and caused negative responses to ambiguous cues ( Saito et al., 2016 ), and anxiety-like behaviors ( Demaestri et al., 2019 ). Presentation of 50-kHz versus 22-kHz playback also resulted in activation of c-Fos in different brain areas ( Beckett et al., 1997 ; Sadananda et al., 2008 ; Ouda et al., 2016 ; Demaestri et al., 2019 ).…”

The Comparison of a New Ultrasound-Induced Depression Model to the Chronic Mild Stress Paradigm

“…According to previous work (Morozova et al, 2016), a comparison of a 3-week exposure to 50 dB-ultrasound of mixed frequencies (“white noise”) at the range of 16–20 kHz did not result in a depressive-like state. The exposure of single frequency US-wave, 22 kHz, leads to anxiety in the first 5 min after exposure (Demaestri et al, 2019), but continuous action of 22 kHz does not lead to behavioral changes, because of an adaptation to the unchangeable stress impact (da Oliveira et al, 2015).…”