Wiebke S. Konerding, Jennifer Brunke, Simone Schehka & Elke Zimmermann
(2011): Is acoustic evaluation in a non-primate mammal, the tree shrew,
affected by context? Anim. Cogn. 14 (6), 787-795.
Abstract: Sound categorisation plays a crucial role for processing
ecological and social stimuli in a species? natural environment. To explore
the discrimination and evaluation of sound stimuli in human babies and
nonhuman primates, a reciprocal habituation-dishabituation paradigm has been
successfully introduced into auditory research. We applied the reciprocal
paradigm for the first time to a non-primate mammal, the tree shrew (Tupaia
belangeri), to examine to what extent non-primate mammals share the ability
to evaluate communication calls with primates. Playback stimuli were three
types of communication calls, differing distinctively in context and
acoustic structure, as well as two artificial control sounds, differing
solely in frequency. We assessed the attention towards the playback stimuli
by the latency to respond to the test stimulus. Subjects evaluated pairs of
communication call types as well as the artificial playback stimuli.
Attention towards the test stimuli differed significantly in strength for
one pair of communication calls, with subjects dishabituating faster to one
category than the other. The comparison of a second pair of communication
calls did not show significant differences. Interestingly, subjects also
evaluated the artificial control sounds. Findings are only partly in line
with results on human and non-human primates. They provided first evidence
that in non-primate mammals acoustic evaluation is not solely affected by
the sound-associated context but is also linked to unusualness and acoustic
cues, such as peak frequency.
URL: http://www.springerlink.com/content/789n728n021126q4/
For reprints please contact Wiebke Konerding (email:
Matz Larsson (2012): Incidental sounds of locomotion in animal cognition.
Anim. Cogn. 15 (1), 1-13.
Abstract: The highly synchronized formations that characterize schooling in
fish and the flight of certain bird groups have frequently been explained as
reducing energy expenditure. I present an alternative, or complimentary,
hypothesis that synchronization of group movements may improve hearing
perception. Although incidental sounds produced as a by-product of
locomotion (ISOL) will be an almost constant presence to most animals, the
impact on perception and cognition has been little discussed. A consequence
of ISOL may be masking of critical sound signals in the surroundings. Birds
in flight may generate significant noise; some produce wing beats that are
readily heard on the ground at some distance from the source.
Synchronization of group movements might reduce auditory masking through
periods of relative silence and facilitate auditory grouping processes.
Respiratory locomotor coupling and intermittent flight may be other means of
reducing masking and improving hearing perception. A distinct border between
ISOL and communicative signals is difficult to delineate. ISOL seems to be
used by schooling fish as an aid to staying in formation and avoiding
collisions. Bird and bat flocks may use ISOL in an analogous way. ISOL and
interaction with animal perception, cognition, and synchronized behavior
provide an interesting area for future study.
URL: http://www.springerlink.com/content/h268w2m8q4u82508/
For reprints please contact Matz Larsson (email:
Lisa A. Heimbauer, Rebecca L. Antworth & Michael J. Owren (2012): Capuchin
monkeys (Cebus apella) use positive, but not negative, auditory cues to
infer food location. Anim. Cogn. 15 (1), 45-55.
Abstract: Nonhuman primates appear to capitalize more effectively on visual
cues than corresponding auditory versions. For example, studies of
inferential reasoning have shown that monkeys and apes readily respond to
seeing that food is present (?positive? cuing) or absent (?negative? cuing).
Performance is markedly less effective with auditory cues, with many
subjects failing to use this input. Extending recent work, we tested eight
captive tufted capuchins (Cebus apella) in locating food using positive and
negative cues in visual and auditory domains. The monkeys chose between two
opaque cups to receive food contained in one of them. Cup contents were
either shown or shaken, providing location cues from both cups, positive
cues only from the baited cup, or negative cues from the empty cup. As in
previous work, subjects readily used both positive and negative visual cues
to secure reward. However, auditory outcomes were both similar to and
different from those of earlier studies. Specifically, all subjects came to
exploit positive auditory cues, but none responded to negative versions. The
animals were also clearly different in visual versus auditory performance.
Results indicate that a significant proportion of capuchins may be able to
use positive auditory cues, with experience and learning likely playing a
critical role. These findings raise the possibility that experience may be
significant in visually based performance in this task as well, and
highlight that coming to grips with evident differences between visual
versus auditory processing may be important for understanding primate
cognition more generally.
URL: http://www.springerlink.com/content/f80n883414132q76/
For reprints please contact Michael J. Owren (email:
Kind regards
Sonja
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Dr. Sonja Amoser
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