This initial experiment was performed to test whether presentation of ultrasonic calls is effective to modify behavior in juvenile rats.
A single trial consisted of a 4-sec silent presentation of two calls made by the same macaque monkey followed by 16 seconds during which the two videos were presented together with a single audio track matching the content and duration of only one of the two videos.
It is interesting to note that in our experiment the trend to turn the head to right side in response to presentation of "play" calls was not significant: in a recent work Molnar et al. [26] reported the results of the first analysis and classification of companion dog barks using machine learning algorithms.
Males responded differently to the presentation of "coo" calls of related and unrelated females, with their reaction depending on the interaction between kin-line (maternal vs paternal kin) and degree of relatedness (r = 0.5, 0.25).
In rhesus macaques, the presentation of coo calls, a vocalization uttered in prosocial contexts, elicited a stronger response in close maternal kin compared to more distant maternal kin or maternally unrelated females (Rendall et al. 1996).
However, none of them emitted 50-kHz calls during presentation of 50-kHz calls, or 22-kHz calls, and only one animal emitted a single call during presentation of noise, meaning that calls were predominantly emitted during inter-stimulus-intervals (not shown in detail).
By Wallace White The New Yorker, March 1 , 1982P. 40 Talk story about a visit to the Explorers Club, on East 70th St., the other afternoon to witness the presentation of something called the Flag for Planet Earth to an explorer who was about to set off on an expedition to the Andes.
Talk story about a visit to the Explorers Club, on East 70th St., the other afternoon to witness the presentation of something called the Flag for Planet Earth to an explorer who was about to set off on an expedition to the Andes.
In a first experiment, conducted in juvenile rats situated singly on a radial maze apparatus, we showed that 50-kHz calls can induce behavioral activation and approach responses, which were selective to 50-kHz signals, since presentation of 22-kHz calls, considered to be aversive or threat signals, led to behavioral inhibition.
After playback of 22-kHz calls, no preference was found (all p-values >.100), whereas animals tended to stay longer in proximal arms than in distal ones after presentation of 50-kHz calls (Z = −1.805, p = .076; arm entries: Z = −1.660, p = .110).110
