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We investigate when infants exhibit knowledge of the familiar size of well‐known objects and whether this knowledge is affected by stimulus format, that is, whether the stimuli are presented as real objects or matched pictures. Infants (130 7‐ and 12‐month‐olds) saw everyday objects such as sippy cups and pacifiers in their familiar size and novel sizes (larger or smaller than the familiar size) placed pairwise within infants' reach. We used a preferential‐looking paradigm to investigate whether infants are able to discriminate familiar from novel sizes. Although, infants of both age groups looked longer toward real objects that were smaller or larger than the familiar size, there were no looking preferences for the pictures. These results suggest that although 7‐ and 12‐month‐olds demonstrate familiar size knowledge for real objects, this understanding does not generalize to pictorial representations of those objects. [ABSTRACT FROM AUTHOR]

Prior knowledge alters perception already on early levels of processing. For instance, judging the display size of an object is affected by its familiar size. Using functional magnetic resonance imaging, we investigated the neural processes involved in resolving ambiguities between familiar object size and physical object size in 33 healthy human subjects. The familiar size was either small or large, and the object was displayed as either small or large. Thus, the size of the displayed object was either congruent or incongruent with its internally stored canonical size representation. Subjects were asked to indicate where the stimuli appeared on the screen as quickly and accurately as possible, thereby ensuring that differential activations cannot be ascribed to explicit object size judgments. Incongruent (relative to congruent) object displays were associated with enhanced activation of the right intraparietal sulcus (IPS). These data are consistent with but extend previous patient studies, which found the right parietal cortex involved in matching visual objects presented atypically to prototypical object representations, suggesting that the right IPS supports view normalization of objects. In a second experiment, using a parametric design, a region-of-interest analysis supported this notion by showing that increases in size mismatch between the displayed size of an object and its familiar viewing size were associated with an increased right IPS activation. We conclude that the right IPS performs view normalization of mismatched information about the internally stored prototypical size and the current viewing size of an object.

Bishop Berkeley suggested that the distance of an object can be estimated if the object’s size is familiar to the observer. It has been suggested that humans can perceive the distance of the object by using such “familiarity” information, but most or many of the prior experiments that found an effect of familiarity were not designed to minimize or eliminate potential influences of: higher cognitive factors on the observers’ responses, or the influences of low-level image features in the visual stimuli used. We looked for the familiarity effect in two experiments conducted both in Russia and Japan. The visual stimuli used were images of three coins used in Russia and Japan. The participants’ depth perception was measured with a multiple-choice task testing the perceived depth-order of the coins. Our expectation was that any effect of “familiarity” on depth perception would only be observed with the coins of the participant’s country. We expected a substantial familiarity effect based on our meta-analysis of the “familiarity” effects observed in prior experiments. But, our results in both experiments showed that the familiarity effect was virtually zero. These findings suggest that the importance of a familiarity effect in depth perception should be reconsidered.

Comparisons of relative size in pictorial spaces under the influence of depth cues were investigated. Using the staircase method, 40 participants adjusted the sizes of blank cards presented in the upper visual field to the size of playing cards presented in the lower visual field. During the presentation of the stimuli, pictorial depth cues were displayed in the computer screen and participants were asked to typify the strategy used to judge the perceived sizes. The horizon and the perspective line gradient contributed to the overestimation of the perceived size of blank cards in about 8 and 12%, respectively, and size comparisons were coherent with the constancy of size.

Comparações de tamanhos relativos em espaços representados pictoricamente foram investigadas sob influência de informações de profundidade. Quarenta participantes ajustaram, pelo método das escadas, os tamanhos de retângulos brancos no campo visual superior para serem percebidos como iguais aos tamanhos de cartas de baralho apresentadas no campo visual inferior. Durante a apresentação dos estímulos, informações pictóricas de profundidade eram disponibilizadas no fundo da tela do computador e os participantes foram solicitados a tipificar a estratégia utilizada para julgar os tamanhos percebidos. A linha do horizonte e o gradiente de linhas de perspectiva favoreceram a superestimação dos tamanhos percebidos em cerca de 8% e 12%, respectivamente, e as comparações de tamanho foram coerentes com a constância de tamanho.Comparisons of relative size in pictorial spaces under the influence of depth cues were investigated. Using the staircase method, 40 participants adjusted the sizes of blank cards presented in the upper visual field to the size of playing cards presented in the lower visual field. During the presentation of the stimuli, pictorial depth cues were displayed in the computer screen and participants were asked to typify the strategy used to judge the perceived sizes. The horizon and the perspective line gradient contributed to the overestimation of the perceived size of blank cards in about 8 and 12%, respectively, and size comparisons were coherent with the constancy of size.

Humans are capable of picking up the invariance of an object's physical speed regardless of the distance from which it is seen. This ability is known as speed constancy. Typically the studies of speed constancy focus on the spatiotemporal cues present in the stimulus. In this work we present a series of experiments that introduce the object's familiarity in combination with other cues to study the speed constancy. The results of the first experiment show that human observers use said familiarity in the estimation of the physical speed of the objects. When distance cues are added to the stimulus, the results show that familiarity helps the system to achieve speed constancy. In the second experiment we remove the contextual cues and show the effect of familiarity on speed constancy. Finally, we propose that familiarity needs to be included in the analysis of speed constancy perhaps by considering the prototypical size of the objects. [ABSTRACT FROM AUTHOR]

To examine sensitivity to pictorial depth cues in young infants (4 and 5 months-of-age), we compared monocular and binocular preferential looking to a display on which two faces were equidistantly presented and one was larger than the other, depicting depth from the size of human faces. Because human faces vary little in size, the correlation between retinal size and distance can provide depth information. As a result, adults perceive a larger face as closer than a smaller one. Although binocular information for depth provided information that the faces in our display were equidistant, under monocular viewing, no such information was provided. Rather, the size of the faces indicated that one was closer than the other. Infants are known to look longer at apparently closer objects. Therefore, we hypothesized that infants would look longer at a larger face in the monocular than in the binocular condition if they perceived depth from the size of human faces. Because the displays were identical in the two conditions, any difference in looking-behavior between monocular and binocular viewing indicated sensitivity to depth information. Results showed that 5-month-old infants preferred the larger, apparently closer, face in the monocular condition compared to the binocular condition when static displays were presented. In addition, when presented with a dynamic display, 4-month-old infants showed a stronger 'closer' preference in the monocular condition compared to the binocular condition. This was not the case when the faces were inverted. These results suggest that even 4-month-old infants respond to depth information from a depth cue that may require learning, the size of faces. [ABSTRACT FROM AUTHOR]

When we recognize an object, do we automatically know how big it is in the world? We employed a Stroop-like paradigm, in which two familiar objects were presented at different visual sizes on the screen. Observers were faster to indicate which was bigger or smaller on the screen when the real-world size of the objects was congruent with the visual size than when it was incongruent--demonstrating a familiar size Stroop effect. Critically, the real-world size of the objects was irrelevant for the task. This Stroop effect was also present when only one item was present at a congruent or incongruent visual size on the display. In contrast, no Stroop effect was observed for participants who simply learned a rule to categorize novel objects as big or small. These results show that people access the familiar size of objects without the intention of doing so, demonstrating that real-world size is an automatic property of object representation. [ABSTRACT FROM AUTHOR]

Abstract: Fast goal-directed actions are supposed to be controlled almost exclusively by bottom-up visual control. This mode of processing has been identified with the so-called dorsal visual stream. It is generally accepted that object recognition, mediated by the ventral stream, must be important for deciding what action to execute depending on the specific object to be grasped and the particular purpose. In contrast, the kinematic parameters of the actual movement itself are supposed to be unaffected by recognition processes. This view was recently challenged by the demonstration of a significant impact of object familiarity on grasping kinematics under binocular visual control (). This effect was observed for very well known everyday objects. However, it remained unclear whether the effect was really due to long-term, everyday familiarity of the target objects or whether it was simply mediated by short-term learning during the experiment. Therefore, we examined whether the same effect could also be found with objects that were geometrically identical to the ones used by and could be distinguished by a pictorial cue but were not associated with long-term, everyday experience. We only found an effect of familiarity under monocular but not under binocular control. Our observation suggests that indeed familiarity exerts an effect on movements under binocular control only if explicit knowledge about the objects is very stable and salient, e.g. after long-term experience. [Copyright &y& Elsevier]

The role of binocular vision in grasping has frequently been assessed by measuring the effects on grasp kinematics of covering one eye. These studies have typically used three or fewer objects presented at three or fewer distances, raising the possibility that participants learn the properties of the stimulus set. If so, even relatively poor visual information may be sufficient to identify which object/distance configuration is presented on a given trial, in effect providing an additional source of depth information. Here we show that the availability of this uncontrolled cue leads to an underestimate of the effects of removing binocular information, and therefore to an overestimate of the effectiveness of the remaining cues. We measured the effects of removing binocular cues on visually open-loop grasps using (1) a conventional small stimulus-set, and (2) a large, pseudo-randomised stimulus set, which could not be learned. Removing binocular cues resulted in a significant change in grip aperture scaling in both conditions: peak grip apertures were larger (when reaching to small objects), and scaled less with increases in object size. However, this effect was significantly larger with the randomised stimulus set. These results confirm that binocular information makes a significant contribution to grasp planning. Moreover, they suggest that learned stimulus information can contribute to grasping in typical experiments, and so the contribution of information from binocular vision (and from other depth cues) may not have been measured accurately. [ABSTRACT FROM AUTHOR]

• 12-month-olds successfully discriminate between familiar- and novel-sized everyday objects. • 7-month-olds successfully discriminate between physically larger and smaller objects. • Familiar size influences behaviors other than interactions that had been shown in prior research. • Knowledge of the familiar size of objects seems to be acquired later than of human faces or bodies. The current study aimed to examine the age at which infants exhibit knowledge of the familiar size of common everyday objects. A total of 65 7- and 12-month-old infants were presented with familiar-sized and novel-sized (i.e., larger or smaller than the familiar size) common everyday objects (i.e., pacifiers and sippy cups), which were placed out of their reach. Both 7- and 12-month-olds' first looks were more frequently directed toward physically larger objects irrespective of whether they were familiar- or novel-sized objects. This finding indicates that initial visual orientation is contingent on the magnitude of the absolute physical size of an object. However, when the entire duration of presentation of the objects (i.e., 10 s) was examined, 12-month-olds' mean looking durations were found to be longer for novel-sized objects than for familiar-sized objects. Thus, although infants in both age groups were able to discern the physical sizes of objects, only 12-month-olds could successfully discriminate between the familiar and novel sizes of everyday objects. Notably, 12-month-olds demonstrated knowledge of familiar size even though the test objects were out of their reach and, consequently, unamenable to manual exploration. [ABSTRACT FROM AUTHOR]