Babies in traffic: Infant vocalizations and listener sex modulate auditory motion perception.

Abstract

Infant vocalizations and "looming sounds" are classes of environmental stimuli that are critically important to survival but can have dramatically different emotional valences. Here, we simultaneously presented listeners with a stationary infant vocalization and a 3D virtual looming tone for which listeners made auditory time-to-arrival judgments. Negatively valenced infant cries produced more cautious (anticipatory) estimates of auditory arrival time of the tone over a no-vocalization control. Positively valenced laughs had the opposite effect, and across all conditions, men showed smaller anticipatory biases than women. In Experiment 2, vocalization-matched vocoded noise stimuli did not influence concurrent auditory time-to-arrival estimates compared with a control condition. In Experiment 3, listeners estimated the egocentric distance of a looming tone that stopped before arriving. For distant stopping points, women estimated the stopping point as closer when the tone was presented with an infant cry than when it was presented with a laugh. For near stopping points, women showed no differential effect of vocalization type. Men did not show differential effects of vocalization type at either distance. Our results support the idea that both the sex of the listener and the emotional valence of infant vocalizations can influence auditory motion perception and can modulate motor responses to other behaviorally relevant environmental sounds. We also find support for previous work that shows sex differences in emotion processing are diminished under conditions of higher stress.

Looming sounds are perceived as faster than receding sounds

“…However, the current finding is likely the result of a well-documented difficulty in applying metric labels accurately to speed stimuli rather than a true perceptual underestimation of the speed of approach (Recarte et al, 2000; Recarte & Nunes, 1996; Triggs & Berenyi, 1982). For example, previous research using the same stimuli required participants to execute a button push when a looming sound source arrived and participants significantly underestimated arrival time indicating a perceived speed that was faster than actual (Neuhoff et al, 2014, 2012; Riskind et al, 2014). Because “labeling” the speed of looming sounds is typically not a priority in a natural environment, the primary concern here was to examine relative differences between conditions rather than absolute estimates of speed.…”

“…Neuroimaging studies have identified specific neural mechanisms that preferentially process looming sounds over auditory motion in other directions (Bach et al, 2008, 2009, 2015; Seifritz et al, 2002). Sex differences and a correlation between physical fitness and the looming bias suggest that the bias is related to the ability to defend oneself in the face of a looming threat (Grassi, 2010; Neuhoff et al, 2009, 2012, 2014; Schiff & Oldak, 1990). Behavioral experiments show that listeners consistently err on the side of safety when perceiving auditory arrival time (Gordon & Rosenblum, 2005; Neuhoff, 2001; Rosenblum et al, 1987, 1993, 2000).…”

“…Sample size was determined by examining prior auditory looming studies that used between-subjects variables. These studies have typically used sample sizes of around 30 per condition (Neuhoff et al, 2014, 2009). However, this sample size was increased because of greater expected variability in the current experiment due to the online nature of the data collection.…”

“…When listeners are asked to predict the arrival time of a looming sound, they exhibit a systematic anticipatory error and perceive that the source has arrived when it is still some distance away1 (Neuhoff, Hamilton, Gittleson, & Mejia, 2014; Neuhoff, Long, & Worthington, 2012; Neuhoff, Planisek, & Seifritz, 2009; Riskind, Kleiman, Seifritz, & Neuhoff, 2014; Rosenblum et al, 1987, 1993; Schiff & Oldak, 1990). This bias can provide a selective advantage by creating a temporal “margin of safety” that affords slightly more time than expected to initiate defensive behaviors in response to the looming object (Freiberg, Tually, & Crassini, 2001; Glatz, Bulthoff, & Chuang, 2014; Neuhoff, 1998, 1999, 2001).…”

Asymmetries in behavioral and neural responses to spectral cues demonstrate the generality of auditory looming bias

“…The phenomenon that approaching sounds are more salient than receding sounds is commonly termed "auditory looming bias." Looming bias is reflected in a broad variety of psychophysical tasks related to salience and alertness: bias in loudness-change estimates (2-4) and judgments of duration (5), improved discriminability of motion speed (6), underestimated distances for egocentrically moving (4) or bypassing sounds (7,8), and reduced reaction time for auditory (3, 9) and visual (3) targets preceded by looming sounds. In animals, looming biases result in faster learning speed during associative conditioning (10) and longer duration of attention (11).…”