Carla Tinti

Visual experience is not necessary for efficient survey spatial cognition: Evidence from blindness

This study investigated whether the lack of visual experience affects the ability to create spatial inferential representations of the survey type. We compared the performance of persons with congenital blindness and that of blindfolded sighted persons on four survey representation-based tasks (Experiment 1). Results showed that persons with blindness performed better than blindfolded sighted controls. We repeated the same tests introducing a third group of persons with late blindness (Experiment 2). This last group performed better than blindfolded sighted participants, whereas differences between participants with late and congenital blindness were nonsignificant. The present findings are compatible with results of other studies, which found that when visual perception is lacking, skill in gathering environmental spatial information provided by nonvisual modalities may contribute to a proper spatial encoding. It is concluded that, although it cannot be asserted that total lack of visual experience incurs no cost, our findings are further evidence that visual experience is not a necessary condition for the development of spatial inferential complex representations.

Spatial biases in peripersonal space in sighted and blind individuals revealed by a haptic line bisection paradigm

Our representation of peripersonal space does not always accurately reflect the physical world. An example of this is pseudoneglect, a phenomenon in which neurologically normal individuals bisect to the left of the veridical midpoint, reflecting an overrepresentation of the left portion of space compared with the right one. Consistent biases have also been observed in the vertical and radial planes. It is an open question whether these biases depend on normal visual experience for their occurrence. Here we systematically investigated this issue by testing blindfolded sighted and early blind individuals in a haptic line bisection task. Critically, we found a robust leftward bias in all participants. In the vertical and radial planes, sighted participants showed a consistent downward and proximal bias. Conversely, the directional bias in blind participants was dependent on the final movement direction; thus, there was no general bias in either direction. These findings are discussed in terms of different reference frames adopted by sighted and blind participants when encoding space.

Crossmodal interaction between the mental number line and peripersonal haptic space representation in sighted and blind individuals

Humans tend to represent numbers in the form of a mental number line. Here we show that the mental number line can modulate the representation of peripersonal haptic space in a crossmodal fashion and that this interaction is not visually mediated. Sighted and early-blind participants were asked to haptically explore rods of different lengths and to indicate midpoints of those rods. During each trial, either a small (2) or a large (8) number was presented in the auditory modality. When no numbers were presented, participants tended to bisect the rods to the left of the actual midpoint, consistent with the notion of pseudoneglect. In both groups, this bias was significantly increased by the presentation of a small number and was significantly reduced by the presentation of a large number. Hence, spatial shifts of attention induced by number processing are not limited to visual space or embodied responses but extend to haptic peripersonal space and occur crossmodally without requiring the activation of a visuospatial representation.

Remembering the silver lining: reappraisal and positive bias in memory for emotion.

Reappraisal and distraction, unlike suppression, are known to decrease the intensity of negative emotion in the short term. Little is known about long-term characteristics associated with emotion regulation strategies, however. In a longitudinal study, we examined the relation between the strategies people reported using to regulate emotions during a stressful situation and their later memory for their emotions. Students in Italy rated the intensity of positive and negative emotions they were experiencing as they prepared for their high school exit exam. They also rated the extent to which they were regulating emotion using reappraisal, distraction, and suppression. Six weeks later, students recalled their pre-exam emotions. The more students reported engaging in reappraisal before the exam, the more they overestimated positive emotion and underestimated negative emotion when recalling their experience. The association between reported reappraisal and memory bias was partially mediated by positive changes over time in students’ appraisals of the exam preparation experience. Reports of engaging in distraction and suppression were not associated with memory bias. Because remembered emotion guides future choices, these findings suggest that reappraisal is a highly adaptive strategy for coping with stressful situations, not only in the short run, but also in the long run.

Memory for an imagined pathway and strategy effects in sighted and in totally congenitally blind individuals

The literature reports mixed results on the imagery abilities of the blind, at times showing a difference between sighted and blind individuals and at other times similarities. However, the possibility that the results are due to different strategies spontaneously used in performing the imagery tasks has never been systematically studied. A large group of 30 totally congenitally blind (TCB) individuals and a group of 30 sighted individuals matched for gender age and schooling were presented with a mental pathway task on a complex two-dimensional (5 x 5) matrix. After administering the task, participants were interviewed in order to establish the strategy they used. Results showed that both sighted and TCB may use a spatial mental imagery, a verbal or a mixed strategy in carrying out the task. Differences between the groups emerged only when last location and then entire pathway had to be remembered rather than just the last position, and were clearly affected by the type of strategy. Specifically, TCB performed more poorly than the sighted individuals when they used a spatial mental imagery strategy, whereas the two groups had a similar performance with a verbal strategy.

Symmetry perception in the blind

Bilateral mirror symmetry, especially vertical symmetry, is a powerful phenomenon in spatial organization of visual shapes. However, the causes of vertical symmetry salience in visual perception are not completely clear. Here we investigated whether the perceptual salience of vertical symmetry depends on visual experience by testing a group of congenitally blind individuals in a memory task in which either horizontal or vertical symmetry was used as an incidental feature. Both blind and sighted subjects remembered more accurately configurations that were symmetrical compared to those that were not. Critically, whereas sighted subjects displayed a higher level of facilitation by vertical than horizontal symmetry, no such difference was found in the blind. This suggests that the perceptual salience of the vertical dimension is visually based.

Pain and emotions reported after childbirth and recalled 6 months later: The role of controllability

The aim of this longitudinal study was twofold: to investigate the relationship between subjectively evaluated control, positive and negative emotional feelings, and pain intensity during childbirth; to assess the recall of these aspects of childbirth experience 6 months after delivery. Participants were 123 women who delivered naturally and spoke fluent Italian. Results showed that both immediately after delivery and 6 months later, higher subjective controllability was related to less severe reported pain, more intense positive emotions and less intense negative emotions. Furthermore, although there was no significant bias in the vividness of the recall, 6 months after delivery women reported higher subjective controllability, more intense positive emotions, less intense negative emotions and less intense pain. It is concluded that in preparing women for childbirth, two aspects deserve particular attention: the enhancement of subjectively perceived controllability and the possibility to work on both negative and positive emotions.

Blind individuals show pseudoneglect in bisecting numerical intervals

Neurologically normal individuals typically show a leftward bias—known as pseudoneglect—in bisecting physical lines as well as numerical intervals. The latter bias may reflect the spatial nature in which numbers are represented (i.e., the mental number line). In previous studies, we found that congenitally blind individuals show such leftward bias in haptic bisection. Here, we demonstrate that blind individuals also show a consistent leftward bias in numerical bisection. The leftward bias was greater when numbers were presented in descending rather than ascending order, and the magnitude of the leftward bias was comparable to that shown by a control group of blindfolded sighted participants. Our findings thus support the view that pseudoneglect operates at a mental representational level rather than being perceptually based. Moreover, the consistent leftward bias shown by blind individuals in both line and numerical bisection suggests that the right hemisphere dominance in spatial processing, resulting in an overestimation of the left side of space, develops even in the absence of any visual input.

Modality-specific Auditory Imaging and the Interactive Imagery Effect

The interactive imagery effect is one piece of evidence to indicate that mental imagery can enhance memory, but it largely has been studied only within the realm of modality-specific visual imagery. The present study demonstrates the possibility of an interactive imagery effect also being found in the auditory modality. The first experiment considered the basic question of whether an interactive auditory imagery effect can be obtained in memory, by contrasting a condition in which auditory images were generated separately with a condition where they were generated in an integrated manner. The second experiment involved a dual-task paradigm, using a concurrent auditory or visual task, to examine whether the integrated images were really created within the auditory modality or were based on visual images. The third experiment tested a possible explanation of the interactive auditory imagery effect. In general, our results show that auditory imagery shares with visual imagery the capacity of allowing efficie...

Allocentric and contra-aligned spatial representations of a town environment in blind people

Evidence concerning the representation of space by blind individuals is still unclear, as sometimes blind people behave like sighted people do, while other times they present difficulties. A better understanding of blind peoples difficulties, especially with reference to the strategies used to form the representation of the environment, may help to enhance knowledge of the consequences of the absence of vision. The present study examined the representation of the locations of landmarks of a real town by using pointing tasks that entailed either allocentric points of reference with mental rotations of different degrees, or contra-aligned representations. Results showed that, in general, people met difficulties when they had to point from a different perspective to aligned landmarks or from the original perspective to contra-aligned landmarks, but this difficulty was particularly evident for the blind. The examination of the strategies adopted to perform the tasks showed that only a small group of blind participants used a survey strategy and that this group had a better performance with respect to people who adopted route or verbal strategies. Implications for the comprehension of the consequences on spatial cognition of the absence of visual experience are discussed, focusing in particular on conceivable interventions.