Body representation and spatial abilities of preterm low birth weight preschool children Beatrix Lábadi (labadi.beatrix@pte.hu) Institute of Psychology, University of Pécs, Ifjúság u. 6. Pécs, 7627 Hungary Enikő Györkő Institute of Psychology, University of Pécs, Hungary Anna Beke Obstetrics and Gynaecology Clinic No.1, Semmelweis University, Budapest, Hungary Abstract Recently an extensive interest has been shown about the role of bodily experience in cognitive processes. However, there The goal of the present study was to investigate the relationship between spatial ability and development of body has been a widespread confusion about the nature of the representation in preterm low birth weight preschool four- mental representation of body (Gallagher, 1986) mostly due year-old children without neurological deficit and typically to the variability of existing taxonomies and models. developing children who were matched by IQ and According to the growing consensus in the field of chronological age. Our findings indicate that children born neuropsychology (Sirigu, Grafman, Bressler, & prematurely with a normal cognitive level may have specific Sunderland, 1991) as well as in developmental psychology difficulties in all levels of body representation which may be associated with the spatial language production. These finding (Slaughter & Heron, 2004) the three-level model is are relevant for understanding the qualitative aspects of body supported which distinguishes (a) a sensori-motor representation and provide practical consequences for early representation of the body; (b) a visual-spatial body intervention of children born prematurely. representation; and (c) a lexical-semantic representation of Keywords: body representation, spatial memory, spatial the body. The sensori-motor level consists of a short-term language, preterm born online representation of the body which is responsible for body movement and not accessible to consciousness. The Introduction visual-spatial representation consists of long-term and general knowledge about the body topography including the Over the past decades, rapid development in the perinatal spatial localization of body parts. The lexical-semantic and neonatal care has increased the survival rate of children representation involves the general knowledge of the body who are born very premature, however, there are potential and its functions involving the naming of body parts or risks for long-term morbidity. Indeed, children born preterm semantic knowledge about the body functions e.g. biological with low birth weight often have neuromotor problems and background. The latter two levels of body representation are are at risk for deficit in cognitive abilities in such accessible to consciousness. neuropsychological domains as memory, attention, The available studies suggest that infants begin learning executive function and language (Mikkola et al. 2005; about their bodies as newborns, but at that time they create Marlow, Henessy, Bracewell & Wolke, 2007). The only a highly schematic representation of human body longitudinal studies emphasize that preterm birth with low (Quinn & Eimas, 1998). The detailed visual-spatial birth weight have long-lasting negative impact on the representations of human body emerge around 15- to 18 cognitive abilities and academic skills in school-aged months when they are capable to discriminate scrambled children (Conley & Bennet, 2000). However, cognitive human body image from non-scrambled body image impairments often cannot be detected clearly until these (Slaughter & Heron, 2004). Interestingly, visual-spatial children begin school. representation of faces emerges earlier than body Most psychological studies of cognitive functioning of representation; even newborns are able to discriminate preterm children investigated the deficit in general domains human faces from scrambled faces (Johnson & Morton, such as global intelligence, attention, perceptual-motor 1991), infants are likely to be born with an innate schema of functioning, executing functioning and memory. These human faces rather than a human body. The detailed visual- assessments demonstrated that children born preterm have spatial representation becomes available from the second or worse neuropsychological outcomes relative to typically third year of life when children begin to develop an explicit developed children. Relatively small number of studies representation of the body and recognize the human shape focused on the specific patterns of the cognitive abilities of with its distinctive configuration and spatial topography preterm children such as spatial abilities, and none of these (Brownell, Nichols, Svetlova, Zerwas & Ramini, 2010). studies investigated the specific impairment in body Based on the previous studies the visual-spatial representation. Some studies reported that being born representation of the body is likely to derive from sensori- prematurely with low birth weight is a risk for deficit in motor representation. This early bodily experience is the spatial memory span and spatial working memory, as well root of the developing body representation, cognitive as recognition memory (e.g., Georgieff & Nelson, 2002). 401 abilities as well as the self. The body awareness is not a sort The control group included children born at term having of separated entity in the world; rather it is a relational no history of perinatal problems. The full-term children with between the body and either the physical and social typical developing characteristics (N=26) were born after 38 environment (Rochat, 2010). Even newborns begin to gestational weeks and individually matched with the develop the implicit bodily self which is embedded in their preterm sample for age, parents education and IQ environment. Shortly after the birth neonates begin to learn (Hungarian version of Brunet-Lezine Test). Full-term the relation between their current capacities (e.g. motor children were recruited from the local preschool selected by skills, bodily constraints) and the environmental conditions. teachers on the average level of the class. But an important question is raised whether children who are born very prematurely before 30 gestational weeks and Materials and Procedure spend their first month(s) in a sensory deprived environment General procedures took place in a quiet lab. Each child are able to develop a typical body representation. was tested individually. Three tasks were conducted to assess body representation of children and additional two Present study tasks evaluated children’s spatial abilities. Children who were born prematurely and spent their first weeks in incubator as a part of the intensive care have been Tasks for body representation frequently reported deficit in sensori-motor domain. The Sensori-motor body representation - Fitting hands task. lack of early physical contact with the world prevents them Here, we investigated children’s ability to reason about their from collecting experience from their own bodies which body size, and shape relative to the objective physical might specifically impact on the later body knowledge and world. In this task children were required to use their own related cognitive abilities. sensori-motor body representation while fitting their actions This study was designed to answer specific questions about to the visual-spatial patterns of the world. Nevertheless, our different aspect of body representation in prematurely born task included only the hands and it did not extend to the children aged between 4 to 5 years. There are both practical whole body. This task required the child to insert their hand and theoretical reasons for addressing the questions of body into one of two apertures to take out a toy from a box. The representation. From a theoretical point of view, the apertures were placed on the top of a box and varied due to research attempts to provide further evidence for the different visual-spatial patterns. To be able to solve the task, childhood development of body representation and its the child required to recognize the spatial relationship of a relation to spatial cognition. The practical aspect of the visual pattern of the aperture and his/her own body research is to provide deeper insights into the possible properties and the bodily action. First, the child had to deficit of body representation in preterm children for early analyze the perceptual constraints of the apertures then educational and rehabilitative intervention to improve the compare them with their own hands properties. Finally, they preterm children’s cognitive and behavioral outcome. were required to choose the correct aperture, orient and adjust their hands to the size, orientation and the shape of Method the aperture in order to insert one hand into the box. In this task we used a box (20 x 30 x 15 cm) with different Participants interchangeable lids. The size of the apertures was adjusted to a typical 5-year-old child’s hand size. Each lid had two We studied 31 preterm children aged between 4 and 5 years, apertures which varied within three dimensions: size, shape who were born before 30 gestational weeks (Mean: 27.93 and orientation. The apertures were presented side by side weeks, SD: 1.63; ranging from 25 to 30 gestational weeks) on the lid and one of two apertures violated the physical and their birth weight ranged from 600 g to 1680 g (Mean: constraints, therefore children were prevented from inserting 1040g, SD: 241 g). Additional 12 children were discarded their hands into this aperture, for example the aperture was because of fussiness (N =4) or incomplete task performance smaller than the child’s hand. Each child performed 9 trials on more than 3 tasks (N=8). Preterm children were enrolled (three per dimension) and the order of the stimuli was via the Department of Pediatric Neurology at the Obstetrics randomized. and Gynaecology Clinic No.1 of Semmelweis University in The experiment was recorded and the tapes were time- Budapest. Prior to the study children were assessed by a coded by digital clock. The hand actions were also coded clinical neuropsychologist and a pediatric neurologist who and analyzed by two independent raters for the purpose of ensured that children are within the normal range of assessing successful choice, reaction time and qualitative intellectual abilities without neurological symptoms, analysis of hand laterality. however they are in the lower part of the normal range as Visual-spatial body representation - Scrambled body task the most of the very preterm children (< 30 gestational To investigate the visual-spatial body representation we week). The inclusion criteria for preterm children were the reproduced scrambled body images used by Slaughter, following: (1) birth at a gestational age of 30 weeks or Heron & Sim (2002). However, we modified them by using younger; (2) no congenital abnormalities; (3) no measurable friendlier children figures instead of adult pictures, and we neurological deficit; (4) no retinopathy or prematurity; (5) also changed the presentation method. We used a pairwise no mental, intellectual disabilities. 402 comparison method with two sets of human body pictures, but the same complexity provides good grounds for testing one for typical body and another for scrambled body. Each path type effects on spatial language use, which is not set consisted of 6 six images, these were black and white available in all languages - for example, English often uses line drawings. The scrambled body set violated the typical the same postpositions for static and goal relations. canonical human body shape, for example legs attached to the shoulders or arms attached to the hip. The pairings of typical and scrambled figure pictures and the side of presentations were randomized across children. The children were asked to decide which picture showed a typical body. We measured the correct responses and analyzed the typical errors. Lexical- semantic body representation - Body part localization task This task investigated children’s ability to locate their body parts on themselves. The task was adopted from adult studies examining the body representation deficits in adults with focal brain damages. Children were asked to point to their own body parts as the examiner named them. This task was divided into two parts, one of which referred to the Fig. 1. Spatial layout in the spatial language task naming of the head parts and the other requested naming the other body parts (we determined 7 standard locations on the In our study the spatial terms were elicited in an head and 24 locations on the body). The whole procedure experimental space consisting of a 1.5 x 1.5 m matrix was recorded and two independent trained raters coded the involving a white mug divided into 16 identical squares performance (within these categories: correct location, with black lines (Fig. 1). We also used five little wooden different body part, refuse). Interraters reliability was .93. chairs made for children with different tops representing animals (e.g. monkey) and fruits (e.g. pumpkin) as reference Tasks for spatial abilities objects. During the experiment these chairs were placed into the matrix, while children were requested to answer 3 types Spatial memory. The spatial memory task was adopted of questions encoding the path e.g. ’Where is the monkey?’ from the Hungarian Version of Snijders – Oomen (static); ’Where do I put the melon?’ (goal); ’Where do I Nonverbal Intelligence Scale for Young Children. This take the apple from?’ (source). We tested the spatial term subtest assesses the spatial location memory in young production within either egocentric or allocentric frame of children. The participant is presented with a little house reference. The experimenter was standing outside of the shape made of paper with six or ten windows depending on matrix and put the target object (chair) to different positions the trials. The windows represent the hiding locations, related to either one or two other objects (chairs) or the child which are displayed in three horizontal rows with 6 depending on the spatial frame of reference. In the windows, and L-shaped configuration with ten windows, allocentric situation the child stood outside of the matrix where these extra four windows are added to one side of the and he/she was required to respond to the experimenter’s house. In each trial, the experimenter places a black kitten questions referring to the relations among the objects (e.g. made of paper into one of the windows then quickly closes ‘The apple is next to the melon’). While in the egocentric all windows and covered the place with a screen for 6 s. situation child sat in the centre of the matrix on a chair and When the screen is removed the children are immediately requested to answer the question from his/her egocentric being requested to point the window where the kitten was viewpoint (e.g. ‘The apple is next to me’). Altogether 12 hid. The number of the correct responses was computed for postpositions were tested in each situation. Children’s the analysis. scores were computed according to the number of correct Spatial language production ‘spatial postposition’ productions. Hungarian language has many possibilities to encode spatial relations: suffixes, postpositions, verbal prefixes and Results adverbs (Lukács, Pléh, & Racsmány, 2007). In this study we Sensori-motor body representation - Fitting hands to a focus on postpositions that are used to encode cognitively visual form task. The hand actions were analyzed due to the complex relations and postpositions providing cue to encode number of correct choices and action duration. the path type in three different forms according to the Correct insertion: For each trial, the correct attempts to dynamic aspect of coding the location and the path. For insert the hand into the aperture were coded and calculated each spatial relation, Hungarian has a static locative term, as a correct choice, but it was only the first attempt that was and two dynamic forms, one encoding the goal or end of the counted. A repeated measures of ANOVA with visual- path; and the other relates to the source or starting point of spatial features (form, size and orientation) as the within the path. All three types can be distinguished linguistically subjects factor and groups (preterm and full-term) as the 403 between subject factor was conducted on the scores of the groups (F (1, 54) = 28.635 p <.000). Children born full-term correct responses. No significant difference was found achieved more than twice as many scores as prematurely between the groups (F (1, 50) = 1.198 p =ns.). But a born children did. We also found differences between the significant effect emerged for visual-spatial feature (F (1, conditions (allocentric and egocentric; F(1, 54) = 11.916 50) = 26.162, p < .000), namely, children tended to perform p<.001). In both groups children performed poorer in the better in trials of orientation than form or size trials. No egocentric condition, they could use more postpositions significant interaction between the group and visual-spatial viewed from outside of the matrix. features was found. Relationship between body representation and spatial Time: we registered the overall duration of action, the time abilities in preterm children. To determine whether preterm from the appearance of the novel lid until the child took out children’s body representations were related to spatial the toy from the box. The incorrect choices were excluded abilities Pearson correlations were calculated among these from the analysis. Repeated measures of ANOVA (2 x 3 x variables with age partialled out from the calculation 3) were used to compare preterm and full-term children as (Table1). Surprisingly, we have not found association between subject variable (preterm vs. full-term) and trials as between the performance in scrambled body task and the well as visual-spatial features (shape, orientation and size) spatial variables. However, positive association was found as within subject variables. We found significant differences between the performance in allocentric spatial language and between the groups for the overall reaction time (F (1, 50) = body localization test (r = .680, p <.21); whereas the 7.609, p <.009). Preterm children (M= 3.93, SE =.198) spent egocentric spatial language showed negative correlation more time to solve this problem than full-term children with the meantime of hand action (r = -.606, p<.048). (M=3.02, SE = .193). We also found differences between Furthermore, the egocentric spatial language showed the visual-spatial categories (F (2,50) = 24.433, p<.000), positive association with the mean correct choices in the where the pairwise comparison showed that the orientation hand task (r = .692, p<.018). In contrast, no significant category (M=2.409, SE =.094) of the visual-spatial pattern association was found between the performance in spatial of the aperture differed either from the shape (M = 4.005, memory and different levels of body representation. SE = .205) or the size (M= 3.787, SE = .236) category. Significant interaction was found among group, trial and Table 1 Intercorrelation among body representation visual-spatial features (F (4, 50) =3.409, p <.011). and spatial ability measures in preterm children Visual-spatial body representation - Scrambled body task We compared the performance between the preterm and Spatial Spatial Spatial full-term group based on the total scores. The analysis language language memory Allocentric Egocentric revealed significant differences (F (1, 60) = 4.901; p< .031). Scrambled body .404 .369 .197 The premature children’s performances were poorer (M= 5.04, SD= .79) than those of the control peers (M= 5.92, Body part .680* .103 .394 SD= .37). These differences can be described by the localization difficulties in the discrimination of the limbs. Whole body Body part localization. One-way analysis of variance Hand fitting .027 .692* .119 Correct choices (ANOVA) was conducted as appropriate on the measures of both dimensions of body representation such as the head and Hand fitting .191 -.606* -.226 the whole body. Significant effect for both dimensions task emerged, and full-term children showed better performance Note df varied from 24-29 depending on the number of children completing either for head dimension (F (1, 47) = 11.609; p<.001) and a given task of overall sample *p < .05 for the whole body dimension (F(1, 47) = 28.975; p<.000). Though, the scores of head were near the ceiling in both To determine to what body representation levels are related, groups (preterm: M =6.32, SD=.72; full-term: M= 6.94, Pearson correlation were computed controlling for age (in SD=.24). Children in the full-term group (M=19.17, months) in the whole sample. The correlations were SD=2.40) exhibited higher performance than their preterm calculated among each score of performance in each body peers (M=14.22, SD = 3.27). representation tasks: scrambled body, body part Spatial memory. Delayed recall score of the two groups localization, fitting hands. Significant correlation (see Table were analyzed by a one-way analysis of variance 5) were observed between the performance of scrambled (ANOVA). The preterm children obtained a lower score (M body task and performance in both body localization tasks = 6.70 SD = 2.57) than did the control group (M=7.84, SD = (for head r =.427, p <.04; r =.471, p<.04; for whole body r 2.22), but no significant difference was found (F (1, 56) = =.471 p<.02) as well as the scores of correct choices in hand 3.122, p= .08). fitting task (r=.427, p <.04). None of the variables of hand Spatial language. A repeated measures of ANOVA (Type fitting task related to the outcome of other body knowledge III) for spatial language (egocentric, allocentric) as within variables. The variables of hand fitting task was associated subjects factor and for groups as between subjects factor only with each other, namely, the means of the correct was conducted. Significant effects were revealed for the 404 responses negatively correlated with the mean time of because even toddlers are capable to discriminate the preadjustment (r= -.545, p<.007). scrambled body from the typical body (Slaughter et al., 2003). In the other body topography (body part localization) Discussion task children were asked to point body parts by name. The Early development of body representation comparing findings showed that full-term children are superior. The preterm and full-term children was investigated in the preterm children’s poor performances remind us of the current study. We reported evidence that children born very neuropsychological deficit at the level of lexical-semantic prematurely, without major neurological deficits and with a body representation, patients (autotopagnosia) with damage normal cognitive level, have specific difficulties in most of to the left parietal area have difficulties to localize their own the body related tasks evaluated at 4 years of age. We body parts when the examiner names them, but they can further found that the reduced performance in body identify parts of inanimate objects (Guariglia et al., 2002). representation is related to spatial language, but not to the These results suggest dissociation between the topographic spatial memory within the preterm group. representation and semantic representation of their own Relative to full-term controls, preterm children in the body. Nevertheless, in our preterm sample we did not find present study showed reduced performance at all levels of that the semantic representation is dissociated from the body knowledge. However, in the task of fitting hand, visuospatial representation, because the children’s where the children are requested to rely on their sensori- performance of body part localization correlated with the motor body representation, both groups are equally good at performance score in scrambled body task (for whole body r scaling their reaching action to size, form and orientation of =.405 p < .04). Notably, the impairments in movement- the aperture. By contrast, previous findings of younger related representations (hand fitting) of one’s body did not children (1.5 - 2 years) showed a poor performance in a correlate with the two other representational levels either in similar scaling task (Ishak and Adolph, 2008), where the preterm sample or in the whole sample. Such findings toddlers frequently attempted to fit their hands into the suggest that sensori-motor body representation might be a impossibly small holes. As Brownell et al (2010) suggested distinct aspect of the body representation. the awareness of body to one’s own body size begins to The last question we addressed refers to the possible emerge in the second year of life but in very limited ways relationship between the body-related representations and and continues developing over the childhood. spatial abilities in preterm children. Our data suggested that In contrast to our prediction, significant differences were not the production of spatial language from two different spatial found between the preterm and full-term groups regarding viewpoints, using allocentric vs. egocentric frame of their performance scores. But they differed in reaction time; reference, was associated with the body representations, preterm children solve this task slower than the control. As namely the preterm children who showed better Milner and Goodale (1995) noted the reaction time of a performance in the body location tasks obtained better particular hand action refers to the transformation speed of outcomes of spatial language production (within the the visuospatial information into motor execution. This allocentric reference). Moreover, the performance of hand process is the function of the dorsal stream, and the longer fitting task also correlated with the spatial language reaction time in preterm children suggests an impairment of productions. It seems that the body might play an important dorsal system functioning. This finding is consistent with role in the spatial representation as the popular theory of other studies (Braddick, Atkinson and Wattam-Bell, 2003, embodiment suggested. The body is used as a sort of Taylor, Jakobson, Maurer and Lewis, 2009) suggesting the reference frame (head-feet, front-back, left-right) which is increased vulnerability of the dorsal stream in children born mapped onto the embodied objects, for example ‘I am prematurely. The different amount of time in transforming behind the melon’ (Lakoff and Johnson, 1999). However, the visuospatial information into execution is likely to the speaker can use a viewer-centered (egocentric or deictic) account for the group differences. As we observed, preterm or object-centered (allocentric or intrinsic) frame of children needed more time to take out the toy from the box reference, and using the allocentric rather than egocentric through the aperture hole because they had not adjusted spatial reference frame to describe the spatial relations can their hand to the visuospatial patterns in advance. refer to the objective and viewpoint independent approach To study children’s knowledge of body topography we of the world. In fact, preterm children’s production of created two age-appropriate modifications of previously egocentric spatial language correlated with the movement- used tasks, we investigated the children’s topographic body related body representation. We propose children who use knowledge using typical human bodies versus scrambled an egocentric view to describe the scene are involved bodies portrayed in various postures. Preterm children bodily. An impaired sensori-motor body representation is tended more frequently to fail to discriminate the canonical not allowed to provide a stable egocentric reference point to body posture from the scrambled body, especially in that determine the locations. case when the arms and legs were interchanged. Our findings suggest that children aged 4 years are able to Conclusion discriminate the canonical human body confidently This study is the first to examine the different levels of body regardless of the body posture. This result is not surprising, knowledge associated with some spatial abilities in children 405 born very prematurely. Relative to full-term sample, preterm Brownell, C., Zerwas, S., Ramini, G. (2007). “So big”: The children showed reduced performance in all levels of body development of body self-awareness in toddlers. Child representation which are associated to the production of Development, 78, 1426-1440. spatial language. Brownell, C. A., Nichols, S. R., Svetlova, M., Zerwas, S., There were theoretical and practical reasons for questioning Ramini, G. (2010). The head bone’s connected to the neck this issue. From a theoretical point of view only limited bone: When do toddlers represent their own body number of studies investigated the possible relationship topography? Child Development, 81, (3) 797-810. between the body representation and spatial cognition, and Conley, D., & Bennett, N. G. (2000). Is biology destiny? none of them focused on the specific developmental risks of Birth weight and life chances. American Sociological preterm birth. Nevertheless, the embodiment theory Review, 65, 458–468. emphasizes the body experience as a ground of many Gallagher, S. (1986). Body Image and Body Schema: A different psychological functions, such as emotions and Conceptual Clarification, Journal of Mind and Behavior cognition. As Esther Thelen (2000) claimed the cognitive 7, 541-554. processes emerge from the bodily experience as someone is K. E., & Lin, G. C. (2008). Perceiving affordances for interacting with the world and this experience is constrained fitting through apertures. Journal of Experimental by the particular motor and perceptual capabilities. On the Psychology: Human Perception & Performance, 34, other hand, the practical reason of this study is to provide 1501-1514. indications for early intervention of cognitive abilities based Marlow, N., Henessy, E. M., Bracewell, M. A., Wolke, D. on the body knowledge that is thought to be a potential (2007). Motor and executive function at 6 years of age predictor of learning disabilities. Our findings suggest that after extremely preterm birth. Pediatrics, 120, 793-804. the early body experience is very important for the later Mikkola, K., Ritari, N, Tommiska, V., Salokorpi, T., development, because infants discover the world through Lehtonen, L. et al. (2005). Neurodevelopmental outcome their bodies, e.g. how their bodies move in space, how their at 5 years of age of a national cohort of extremely low bodies relate to the objects in the world (Adolph and Berger, birth weight nfants who were born in 1996–1997. 2006); while they are capable to differentiate their bodies Pediatrics 116. 1391 -1400. form the physical world from the first year of the life. Moore, C. (2007). Understanding self and others in the Therefore, from a practical view, the early intervention to second year. In. C. Brownell, C. Kopp (Eds.) Transitions improve these children’s body knowledge at all levels is in early socioemotional development: The toddler years. worthy of consideration. New York: Guilford, 43-65. Limitations. Our results must be viewed with caution for Quinn, P. C., Eimas, P. D. (2000). The emergence of some reasons. First, we did not control the birth weight category representation during infancy: Are separated and relative to gestational weeks, our preterm sample involved conceptual process required? Journal of Cognition and children with relatively wide range (600 g to 1680 g) Development, 1, 55-61. however previous studies showed that the birth weight (as a Quinn, P. C., Eimas, P. D. (1998). Evidence for a global degree of prematurity) is a good predictor of the future categorical representation of humans by young infants. cognitive abilities. Second, it is not clear whether the results Journal of Experimental Child Psychology, 69, 151-174. of preterm children are specific to body representations or Rochat, P. (2010). The innate sense of the body develops to the problem in body representation itself is a consequence become a public affair by 2-3 years. 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