1,721,245 research outputs found
Rotational Bias in Mosquitofish (Gambusia holbrooki): The Role of Laterality and Sun-compass Navigation
No full textAnimals' representation of enclosed spaces: Evidence for use of a similar frame of reference following different disorientation procedures in the domestic chick (gallus gallus).
No full textA wide range of vertebrate species has been proved to be capable, following passive disorientation, to
reorient into enclosures of different shapes using the metrical distribution of surfaces as surfaces and the
geometric sense of left and right. Two procedures can be used to get a subject to loose its orientation:
The subject itself can be rotated with the eyes closed or in the dark (viewer-movement procedure) or the
external enclosure can be rotated while the subject stays still in a fixed position with the eyes closed or
in the dark (i.e., without the possibility to notice any change outside; space-movement procedure).
Although the 2 procedures are equivalent in that both cause a change in the spatial relationships between
the viewer and the external layout, it has been suggested on the basis of research in human infants that
they may involve the use of different frames of reference to reestablish one’s bearing and relocate the
target. However, no comparison between viewer- and space-movement procedures has been carried out
in nonhuman species. Here, the authors show that newborn domestic chicks (Gallus gallus) can reorient
effectively irrespective of the specific disorienting procedure applied. The results are discussed in
comparative and developmental perspectives
The use of proportion by young domestic chicks (Gallus gallus)
No full textWe investigated whether 4-day-old domestic
chicks can discriminate proportions. Chicks were trained to
respond, via food reinforcement, to one of the two stimuli,
each characterized by different proportions of red and
green areas ( vs. ). In Experiment 1, chicks approached
the proportion associated with food, even if at test the
spatial dispositions of the two areas were novel. In
Experiment 2, chicks responded on the basis of proportion
even when the testing stimuli were of enlarged dimensions,
creating a conflict between the absolute positive area
experienced during training and the relative proportion of
the two areas. However, chicks could have responded on
the basis of the overall colour (red or green) of the figures
rather than proportion per se. To control for this objection,
in Experiment 3, we used new pairs of testing stimuli, each
depicting a different number of small squares on a white
background (i.e. 1 green and 3 red vs. 3 green and 1 red or
5 green and 15 red vs. 5 red and 15 green). Chicks were
again able to respond to the correct proportion, showing
they discriminated on the basis of proportion of continuous
quantities and not on the basis of the prevalent colour or on
the absolute amount of it. Data indicate that chicks can
track continuous quantities through various manipulations,
suggesting that proportions are information that can be
processed by very young animals
From Small to Large: Numerical Discrimination by Young Domestic Chicks (Gallus gallus).
Get PDFHuman adults and nonhuman primates share a subset of nonverbal numerical skills that are considered
the evolutionary foundation of more complex numerical reasoning. Intriguing experiments have shown
that 10- to 12-month-old infants are able to distinguish between large (8 vs. 12) and small (1 vs. 2, 1 vs.
3, 2 vs. 3) sets of objects but seem incapable of comparing quantities that fall in the middle area between
large and small numerosities, such as 1 versus 4. This finding suggests that there are two separate
nonverbal numerical systems. Other researchers argue that there is continuity in the representation of
numbers. Experimental evidence demonstrating that newborn chicks are able to process addition and
subtraction such as (4 –1) versus (1 1 1) lends support to the latter hypothesis. Here, using an
experimental paradigm to test numerical discrimination, we demonstrated that newborn chicks are able
to distinguish between some numerical comparisons, such as 2 vs. 3, 2 vs. 8, 6 vs. 9, 8 vs. 14, 4 vs. 6,
and 4 vs. 8. These findings support the hypothesis that a single system processes both small and large
numerosities. The results of these experiments demonstrate that small and large numbers can be
discriminated via “analogue magnitude” system (AMS). Those data can be accounted for in terms of a
select mechanism prompting the functioning of either system and, therefore, a different processing of the
stimuli. When the modality of presentation of the stimuli focuses the attention on the whole collection,
the elaboration would be carried out by the AMS
Left-right asymmetries in spatial numerical processing. Behavioural evidence from an animal model: the domestic chick (Gallus gallus)
No full textYoung domestic chicks, when trained to identify the 4th element in a series of identical elements, and then required to respond to a left/right oriented series, referred as correct the 4th element from the left end, and not the 4th from the right end (Rugani et al. 2007, 2010, 2011).
To disentangle the engagement of either hemisphere in dealing with the ordinal task and in determining the leftward bias, visual input was restricted to one eye, so as to determine the functioning of the contralateral hemisphere.
Four-days-old chicks (N=10) were binocularly trained to peck at the 4th target element in a series of 10 identical and sagittaly aligned (with respect to the chick’s starting position) elements. At test, the series was rotated by 90°. The test was conducted in three different conditions of vision: binocular, right monocular and left monocular. When binocularly tested, chicks generalized to the 4th element from the left (p<0.01). In right monocular condition chicks generalized to the 4th element from the right (p<0.01) and in left monocular condition to the 4th element from the left (p<0.01).
These results indicate that ordinal information is bilaterally represented in the cerebral hemispheres. Whenever both hemispheres are processing the information an extra-activation of the right hemisphere would take place, favoring an allocation of attention into the left hemispace and thus producing a bias to ‘‘count’’ selectively from left to right
Lateralization of displays during aggressive and courtship behaviour in the Siamese fighting fish (Betta splendens)
No full text
At the root of the left–right asymmetries in spatial–numerical processing: From domestic chicks to human subjects
No full textIn this review, we discuss evidence showing that birds (Gallus gallus and Nucifraga columbiana)
represent numerical magnitudes as being oriented from left to right. Subjects, trained to identify a target
element (i.e. the 4th) in a series of sagittally oriented identical elements, when required to generalise on
an identical series oriented spatially from left to right, correctly identified the target element “counting”
from the left of the array. Moreover, chicks, when presented with sets of 5 vs. 10 or 6 vs. 9 imprinting
objects, which were made to disappear one at a time behind one of two identical screens, spontaneously
inspected the screen which occluded the larger set. Interestingly, chicks scored a higher percentage of
correct choices when the larger of the two sets was on their right side. Similarities with the phenomenon
of the spatially oriented (left to right) number line in humans are discussed. Animal models promise a
fresh approach to the understanding of developmental mechanisms underlying the expression of
knowledge, offering attractive arguments for doubting the uniqueness of human numerical cognition
“La conoscenza scientifica è come aggirarsi con una torcia tra le stanze di un grande castello”. Intervista a Giorgio Vallortigara
No full textIl contributo consiste in un'intervista a Giorgio Vallortigara, professore di Neuroscienze presso il Centro Interdipartimentale Mente/Cervello dell'Università di Trento e uno dei massimi esperti mondiali di intelligenza animale. Il dialogo ruota attorno al ruolo svolto dal concetto di senso immerso nelle sue ricerche. Tra gli argomenti trattati: il significato delle recenti scoperte sul funzionamento del cervello umano e animale; l'inadeguatezza del modo in cui viene solitamente tracciata la frontiera tra uomo e animale; il rapporto tra scienze umane e naturali; la qualità pragmatica dell'intelligenza umana; la selezione naturale come principio generale di tutti i fenomeni della vita; l'impatto della rivoluzione dell'IA sui nostri tentativi di comprendere come gli organismi biologici creano significato; e il senso ultimo dell'impresa scientifica
Response to comment on "Number-space mapping in the newborn chick resembles humans’ mental number line"
No full textMangalam and Karve raise concerns on whether our results demonstrate a mental number line, suggesting auxiliary experiments. Further data analyses show that their methodological concerns are not founded. Harshaw suggests that a side bias could have affected our results. We show that this concern is also unfounded
- …
