Changes in reality monitoring and episodic memory in early childhood

The purposes of this research were to examine the developmental relation between reality monitoring and episodic memory, to link reality monitoring to autobiographical memory by using extended naturalistic events, and to examine prefrontal functioning as a potential contributor to development in reality monitoring and episodic memory. In Experiment 1, 4-year-olds were worse than 6- or 8-year-olds at reality monitoring after a week delay, despite the fact that they remembered more about real than imagined events and remembered different aspects of each. In Experiments 2 and 3, reality monitoring and episodic memory were evaluated for 4- and 6-year-olds immediately after the events occurred and, in Experiment 3, again after a week delay. Reality monitoring was at higher levels for both age groups, but age differences remained. These data suggest that preschoolers' difficulties with reality monitoring result from a combination of episodic memory deficits and strategic differences. In addition, correlation analyses more directly linked preschoolers' reality monitoring to episodic memory and supported the hypothesis that episodic memory development is related to prefrontal functioning.     

Whorf versus Socrates, round 10

A recent paper by Dehaene, Izard, Pica and Spelke examined geometric concepts among the Munduruku, an Amazonian group without many linguistic terms for spatial relations, and without maps or formal schooling. Their profile of strengths and weaknesses provides new insights into the nature of the human mind and the importance of culture and language to the development of thought.     

Preexisting knowledge versus on-line learning: what do young infants really know about spatial location?

Contemporary knowledge of infant cognition relies heavily on violation-of-expectation experiments. However, there are two ways to conceptualize what occurs in such studies. Babies may react to anomalous test events because of preexisting world knowledge. Alternatively, they may react because they have learned about events during the familiarization period. One way to distinguish these possibilities is to contrast familiarization with everyday versus anomalous events. In the studies we report here, we used this method to probe the nature of 5-month-olds' expectations about the locations of objects hidden in sand and later revealed. In Experiment 1, infants who initially saw everyday events did react to anomalous ones, as found previously, whereas infants who initially saw anomalous events did not react to everyday events. In Experiment 2, two alternative explanations of this pattern were ruled out. We conclude that by the age of 5 months, infants have expectations regarding the location of objects in continuous space.     

Socioeconomic status modifies the sex difference in spatial skill

We examined whether the male spatial advantage varies across children from different socioeconomic (SES) groups. In a longitudinal study, children were administered two spatial tasks requiring mental transformations and a syntax comprehension task in the fall and spring of second and third grades. Boys from middle- and high-SES backgrounds outperformed their female counterparts on both spatial tasks, whereas boys and girls from a low-SES group did not differ in their performance level on these tasks. As expected, no sex differences were found on the verbal comprehension task. Prior studies have generally been based on the assumption that the male spatial advantage reflects ability differences in the population as a whole. Our finding that the advantage is sensitive to variations in SES provides a challenge to this assumption, and has implications for a successful explanation of the sex-related difference in spatial skill.     

Understanding spatial transformations: similarities and differences between mental rotation and mental folding

Mental rotation and mental folding, two widely used measures of spatial ability, both require the dynamic spatial transformation of objects with respect to their internal spatial structure. Traditionally, however, these two skills have been considered quite distinct, based primarily on factor analyses of psychometric data. This paper reviews the similarities and differences between mental rotation and mental folding from a variety of perspectives, including their definitions, component cognitive processes, neurological bases, developmental trajectories, malleability, predictive validity, and psychometric properties. We conclude that mental rotation and mental folding are similar in many respects. However, the tasks differ in whether they require rigid or non-rigid transformations of objects. In addition, mental rotation shows robust sex-related differences whereas mental folding does not. We also identify specific questions for which research is lacking.     

Development of mental rotation in 3- to 5-year-old children

We assessed 3- to 5-year-olds’ mental rotation abilities using a new puzzle paradigm. It allows for assessment of mental rotation abilities in children younger than 5 years, using a task comparable to ones used with older children and adults. Children saw pairs of asymmetrical ghost figures, either as three-dimensional cut-outs or two-dimensional paper versions, in seven orientations. One of the ghosts fit into a hole if rotated right-side up – the other ghost was its mirror image and would not fit. Children were asked to turn the ghosts in their heads and choose the one that would fit into the hole. The number of children who chose the correct ghost above chance in the three-dimensional version of the task increased dramatically from 10% of 3-year-olds to 95% of 5-year-olds; average accuracy also increased significantly, from 54% to 83%. The two-dimensional paper version yielded similar results. These results indicate considerable development in mental rotation between 3 and 5 years.     

A slippery directional slope: Individual differences in using slope as a directional cue

Navigators rely on many different types of cues to build representations of large-scale spaces. Sloped terrain is an important cue that has received recent attention in comparative and human spatial research. However, the studies to date have been unable to determine how directional slope information leads to more accurate spatial representations. Moreover, whereas some studies have shown that the inclusion of slope cues improves performance on spatial tasks across participants (Kelly, 2011; Restat, Steck, Mochnatzki, & Mallot, 2004), other research has suggested individual differences in the benefits of slope cues (Chai & Jacobs, 2010; Nardi, Newcombe, & Shipley, 2011). We sought to clarify the role of sloped terrain in improving the representation of large-scale environments. In Experiment 1, participants learned the layout of buildings in one of two desktop virtual environments: either a directionally sloped terrain or a completely flat one. Participants in the sloped environment outperformed those in the flat environment. However, participants used slope information as an additional cue, rather than as a preferred reference direction. In Experiment 2, the two virtual environments were again either flat or sloped, but we increased the complexity of the relations between the slope and the path. In this experiment, better performance in the sloped environment was only seen for participants with good self-reported senses of direction. Taken together, the studies show that slope provides useful information for building environmental representations in simple cases, but that individual differences emerge in more complex situations. We suggest that good and bad navigators use different navigational strategies.     

Book reviews

Ellis, A. W. (Ed.). Progress in the psychology of language, Vols 1 and 2. London: Erlbaum Associates. 1985. Pp. vii+247 (Vol.1), v+274 (Vol.2). ISBN 0-86377-027-4 (Vol.1), 0-86377-028-2(Vol.2). £19.65. each.

Eysenck, M.W. A hondbook of cognitive psychology. London: Lawrence Erlbaum Associates. 1984. Pp. 417. ISBN 0-86377-016-9. Hardback £26.95; paperback £8.95.

Roy, E. A. (Ed.). Neuropsychological studies of apraxia and related disorders. Amstrdam: North olland. 185 Pp. 414. ISN 0-444-87669-3. $60.00.

Fischer, K. W. and Lazerson, A. Human development frm conception through adolescence. New York: W. H. Freman. 1984. Pp. 747. ISBN 9-7167-1575-9. £24.95.

Sloboda, J. A. The musical mind. Oxford: Clarendon Press, 1985. Pp. vii+291. ISBN 0-19-852114-6 (hardback) £20; ISBN 0-19-852128-6 (paperback) £9.65.

Howell, P., Cross, I. and West, R. Musical structure and cognition. London: Academic Press. Pp. xiv+ 338. ISBN 0-12-357170-7. £44.     

Unawareness of impaired face recognition

We report investigations of the face processing abilities of SP, a right-handed woman who had suffered a subarachnoid haemorrhage from a right middle cerebral artery aneurysm. Although she could correctly assign visual stimuli to the 'face' category without difficulty, SP performed poorly on all other face processing, tasks, including 'closure' (Mooney faces), perception of facial expression, unfamiliar face matching, and identification of familiar faces. Identification of familiar people from nonfacial cues (names) remained relatively well-preserved, but severe impairments were evident on all face recognition tasks. Her errors mostly involved either failures to find a face familiar at all, or misidentification as another familiar person. In face-name learning tasks, there was evidence of 'covert' recognition of faces she failed to recognize overtly. SP's face processing impairment remained stable across a 20-month period of investigation, yet throughout this period she did not think that she had any problems in face recognition, and continued to show lack of insight into this impairment even when directly confronted with its consequences on formal testing. In contrast, SP showed adequate insight into other physical and cognitive impairments produced by her illness, including poor memory, hemiplegia, and hemianopia. We propose that her lack of insight into her face recognition problems involves a deficit-specific anosognosia, resulting from impairment of domain-specific monitoring abilities.