Do infant rats cry?

Abstract

In the current revival of interest in the emotional and mental lives of animals, many investigators have focused attention on mammalian infants that emit distress vocalizations when separated from the home environment. Perhaps the most intensively studied distress vocalization is the ultrasonic vocalization of infant rats. Since its discovery, this vocalization has been interpreted both as a communicatory signal for the elicitation of maternal retrieval and as the manifestation of emotional distress. In contrast, the authors examined the cardiovascular causes and consequences of the vocalization, and on the basis of this work, they hypothesized that the vocalization is the acoustic by-product of the abdominal compression reaction (ACR), a maneuver that results in increased venous return to the heart. Therefore, the vocalization may be analogous to a sneeze, serving a physiological function while incidentally producing sound.

Actions speak louder than words: An elaborated theoretical model of the social functions of self-injury and other harmful behaviors

“…Crying can be thought of as a handicap as well given that it is difficult to fake, costly to produce in that it blurs vision, and it leaves a physical trace once engaged (Hauser, 1996). Like NSSI, crying behavior also serves an automatic function in the form of arousal reduction (Blumberg & Sokoloff, 2001;Gross, Frederickson, & Levenson, 1994;Hendriks et al, 2007;Rottenberg, Wilhelm, Gross, & Gotlib, 2003). In support of the escalation of communication hypothesis, prior work on infant crying has shown that higher intensity crying elicits more rapid caregiving than lower intensity crying (e.g., Wood & Gustafson, 2001).…”

“…Crying is perhaps most often conceptualized as a behavioral signal of distress that serves a social function in the form of eliciting caregiving behavior from others (Blumberg & Sokoloff, 2001;Hendriks, Rottenberg, & Vingerhoets, 2007;Zeifman, 2001). Crying can be thought of as a handicap as well given that it is difficult to fake, costly to produce in that it blurs vision, and it leaves a physical trace once engaged (Hauser, 1996).…”

Neural circuits underlying crying and cry responding in mammals

“…This research has not been without its critics. Noteworthy was a paper by Blumberg and Sokoloff [8], who attempted to discredit claims that findings based on the most widely used animal model, the laboratory rat, were a valid measure of emotional expression, but were, instead, a byproduct of reflexive abdominal compression. Their assertion was skillfully and eloquently put to rest in a rejoinder by Panksepp [86].…”

“Laughing” rats and the evolutionary antecedents of human joy?

“…Readers interested in an example of ongoing skepticism with regard to existing work on separation distress in animals, as well as related scientific issues, can find that topic debated in a series of recent articles [8,59]. We feel the neuroscience community does need to try to deal more forthrightly with the critically important affective functions of the brain.…”