Early neuropsychological correlates of later clock drawing and clock copying abilities among school aged children.

Although widely used in empirical study and bedside neuropsychological evaluation of geriatric populations, there is little literature on clock copying and drawing among children. However, existing research suggests that clock drawing tests (CDTs) may be effective and efficient tools for assessing neurocognitive development in children. This paper reports data on clock drawing on demand (CDT-D) and clock drawing to copy (CDT-C) among a non-clinical sample of elementary school aged children and identifies predictive relationships between earlier measures of executive function, visuo-construction, and visual-motor coordination and CDT performance 3 years later. Similar to findings with adult samples, analyses revealed better performance on copying than on drawing. Longitudinal analyses indicate that general intelligence significantly predicted performance on both tasks. Visual-motor coordination only predicted performance on the drawing on demand subtest of the CDT.     

Developmental changes in face processing skills

Expertise in processing differences among faces in the spacing among facial features (second-order relations) is slower to develop than expertise in processing the shape of individual features or the shape of the external contour. To determine the impact of the slow development of sensitivity to second-order relations on various face-processing skills, we developed five computerized tasks that require matching faces on the basis of identity (with changed facial expression or head orientation), facial expression, gaze direction, and sound being spoken. In Experiment 1, we evaluated the influence of second-order relations on performance on each task by presenting them to adults (N=48) who viewed the faces either upright or inverted. Previous studies have shown that inversion has a larger effect on tasks that require processing the spacing among features than it does on tasks that can be solved by processing the shape of individual features. Adults showed an inversion effect for only one task: matching facial identity when there was a change in head orientation. In Experiment 2, we administered the same tasks to children aged 6, 8, and 10 years (N=72). Compared to adults, 6-year-olds made more errors on every task and 8-year-olds made more errors on three of the five tasks: matching direction of gaze and the two facial identity tasks. Ten-year-olds made more errors than adults on only one task: matching facial identity when there was a change in head orientation (e.g., from frontal to tilted up). Together, the results indicate that the slow development of sensitivity to second-order relations causes children to be especially poor at recognizing the identity of a face when it is seen in a new orientation.     

Smaller holistic processing of faces associated with face drawing experience

The type of experience involved with an object category has been regarded as one important factor in shaping of the human object recognition system. Laboratory training studies have shown that different kinds of learning experience with the same set of novel objects resulted in different perceptual and neural changes. Whether this applies to natural real-world objects remains to be seen. We compared two groups of observers who had different learning experiences with faces, using holistic processing as a dependent measure. We found that, while ordinary observers had extensive individuation experience with faces and displayed typical holistic face processing, art students who had acquired additional experience in drawing faces, and thus in attending to parts of a face, showed less holistic processing than did ordinary observers. These results converge with laboratory training studies on the role of type of experience in the development of different perceptual markers for different object categories. It is thus insufficient to categorize expertise simply in terms of object domains (e.g., expertise with faces). Instead, perceptual expertise should be classified in terms of the underlying process or task demand.     

Inner and outer face perception in children with autism.

Possible peculiarities in face perception in the autistic population were explored through two experiments. Fourteen autistic children (mean age=10 years 1 month) were individually matched to verbal mental age (VMA) and chronological age (CA) subjects. In a first experiment, subjects were to match faces on the basis of either their outer (hair, chin, ears) or their inner (eyes, nose, mouth) aspects. Autistic children performed equally well in both conditions, while VMA-matched children performed better in the outer than the inner part condition. In a second experiment, chimeric faces consisting of the outer part of an individual's face and the inner part of another individual's face were presented to the subjects. None of the groups showed a preference for neither the outer nor the inner part of the face in this condition. Results were discussed in terms of the existence of a local visual processing strategy in this population.     

Developmental changes in face processing: results from multidimensional scaling

Multidimensional scaling procedures were used to investigate developmental changes in the ability to process previously unfamiliar faces. Eighty male subjects, aged 7, 9, 12, or adult, rated the similarity of pairs of faces. The faces were presented to subjects in either the upright or the inverted orientation. Multidimensional scaling analyses suggest that subjects of all ages use similar information in judging the similarity of faces. However, for upright faces, individual subjects under age 10 seem to use fewer features at a time. The results argue against a qualitative shift in face processing at age 10, and suggest that the improvement in face recognition ability noted at this age is due at least in part to an increased ability to consider more features simultaneously.     

Interrater reliability of scores derived from two methods for scoring the clock drawing test

Scores on the Clock Drawing Test have long been considered a useful screening tool for neuropsychological dysfunction, and a number of scoring methods have been developed to evaluate various aspects of performance. This study compared quantitative and qualitative scoring by briefly trained students on 145 clock drawings produced by patients in a geriatric psychiatry outpatient clinic to estimate the interrater reliability of the methods, user's acceptance of the methods, and whether the methods provide differential diagnosis. Both systems showed acceptable interrater reliability. Using the quantitative method, raters scored drawings by patients with organic mental disease as more impaired than those patients diagnosed as depressed or schizophrenic. Results suggest that the Clock Drawing Test is a reliable screening tool for cognitive impairment in a geropsychiatric population, but the scoring methods examined do not yet appear psychometrically sound enough to provide a differential diagnosis.     

Early differentiation between drawing and writing in Chinese children

Children under 3½ years of age or so are often thought to produce the same types of scribbles for writing and drawing. We tested this idea by asking Chinese 2- to 6-year-olds to write and draw four targets. In Study 1, Chinese adults judged the status of the productions as writings or drawings. The adults performed significantly above the level expected by chance even with the productions of 2- to 2½-year-olds. In Study 2, we examined specific characteristics of the children’s writings and drawings. Although the younger children’s scribbles bore little resemblance to the correct characters, they tended to be smaller, sparser, and more angular than their artwork, with less filling in. Differences were also found in paper use and implement use. Children did not appear to distinguish writing from drawing for their own names before they did so for other targets.     

A note on the kinematcis of drawing movements in children

The relationship between instantaneous tangential velocity and radius of curvature (power 1/3) that is characteristic of adult subjects was found to be already present in children 3 to 11 years old. The correlation coefficient between these two parameters increases gradually with age without apparent discontinuities. However, even at the upper limit of the age range examined, the values are still lower than in the adults.     

Clock drawing in spatial neglect: A comprehensive analysis of clock perimeter, placement, and accuracy

Clock drawings produced by right-brain-damaged (RBD) individuals with spatial neglect often contain an abundance of empty space on the left while numbers and hands are placed on the right. However, the clock perimeter is rarely compromised in neglect patients' drawings. By analysing clock drawings produced by 71 RBD and 40 healthy adults, this study investigated whether the geometric characteristics of the clock perimeter reveal novel insights to understanding spatial neglect. Neglect participants drew smaller clocks than either healthy or non-neglect RBD participants. While healthy participants' clock perimeter was close to circular, RBD participants drew radially extended ellipses. The mechanisms for these phenomena were investigated by examining the relation between clock-drawing characteristics and performance on six subtests of the Behavioral Inattention Test (BIT). The findings indicated that the clock shape was independent of any BIT subtest or the drawing placement on the test sheet and that the clock size was significantly predicted by one BIT subtest: the poorer the figure and shape copying, the smaller the clock perimeter. Further analyses revealed that in all participants, clocks decreased in size as they were placed farther from the centre of the paper. However, even when neglect participants placed their clocks towards the centre of the page, they were smaller than those produced by healthy or non-neglect RBD participants. These results suggest a neglect-specific reduction in the subjectively available workspace for graphic production from memory, consistent with the hypothesis that neglect patients are impaired in the ability to enlarge the attentional aperture.     

Developmental changes in visual scanning of face and nonface patterns by infants

The eye movements of infants, aged 4–5, 7–8, and 10–11 weeks, were recorded while they viewed either a representation of a face or a nonface stimulus. Presentation of the visual stimulus was paired with the presentation of an auditory stimulus (either voice or tone) or silence. Attention to the visual stimulus was greater for the older two groups than for the youngest group. The effect of the addition of sound was to increase attention to the visual stimulus. In general, the face was looked at more than the nonface stimulus. The difference in visual attention between the face and the nonface stimulus did not appear to be based solely on the physical characteristics of the stimuli. A sharp increase in the amount of looking at the eyes of the face stimulus at 7–8 weeks of age seemed to be related to a developing appreciation of the meaning of the face as a pattern.     

Developmental features of speech-sound production in language-impaired children

The speech-sound production of severely language-impaired children was monitored in a longitudinal study. In order to generalize findings, acoustical, phonemic, and clinical observation data were collected from 30 children. Results showed that speech-sound acquisition goes through a hierarchical sequence of development and that speech-sound production will deteriorate in a predictable manner depending on the pathology. The authors hypothesize a speech-sound acquisition model, SSAM, based on the development observed.This project was supported by the Swiss National Foundation for Scientific Research-Projects No. 3.237.69, 3.448.70, and 3.902.72-and by North Carolina State University Research and Development Grant 056.     

Developmental differences in drawing performance of the dominant and non-dominant hand in right-handed boys and girls

This paper addresses the development of fine motor skills in the dominant and non-dominant hand. A total of 60 right-handed children, aged 4-12 years old, were divided in five groups of 12 children, with six girls and six boys in each group. The children were presented with drawing tasks that had to be performed with the dominant and non-dominant hand. Small or large targets had to be connected by lines making either a zigzag (discrete) or slalom (continuous) movement. For each task, effects of age group, gender, hand, and target size were examined for drawing time, percentage of stop time, drawing distance, velocity, and errors. Comparison of stop times in both tasks showed that the zigzag task was performed in a discrete way while the slalom task was performed more continuously, except in the youngest children, who performed both tasks in a discrete manner. With increasing age the children performed the tasks faster, more accurate and with shorter stops. No significant differences were found between boys and girls. While a shorter drawing distance and less errors were observed for the dominant hand in both tasks, drawing time and velocity were not significantly different between both hands. However, the percentage of stop time was higher for the dominant hand. Moving to smaller targets resulted in slower and less accurate performance. A significant interaction of age group and hand was found for errors in both tasks, and for stop time and velocity in the slalom task, suggesting differential maturational changes for both hands in discrete and continuous drawing tasks.     

Modeling face identification processing in children and adults

Two face identification experiments were carried out to study whether and how children (5-year-olds) and adults integrate single facial features to identify faces. Using the paradigm of the Fuzzy Logical Model of Perception each experiment used the same expanded factorial design, with three levels of eyes variations crossed with three levels of mouth variations as well as their corresponding half-face conditions. In Experiment 1, an integration of facial features was observed in adults only. But, in adjusting the salience of the features varied, the results of Experiment 2 indicate that children and adults evaluated and integrated information from both features to identify a face. A weighted Fuzzy Logical Model of Perception fit the judgments significantly better than a Single Channel Model and questions previous claims of holistic face processing. Although no developmental differences in the stage of the integration of facial information were observable, differences between children and adults appeared in the information used for face identification.     

Effect of postural instability on drawing errors in children: a synchronized kinematic analysis of hand drawing and body motion

To investigate the role that postural stability plays in fine motor control, we assessed kinematics of the head, shoulder, elbow, and the pen during an accuracy drawing task in 24 children. Twelve children were classified into an accurate drawing (AD) group and 12 children into an inaccurate drawing (ID) group based on a manual dexterity task from the movement assessment battery for children [Henderson, S. E., & Sugden, D. A. (1992). Movement assessment battery for children. London: Psychological Corporation.]. Their parents completed a questionnaire to assess children's inattention, hyperactivity, and impulsivity. An electromagnetic tracking system was used to monitor 3-D kinematic data of the body parts, while 2-D kinematic data of pen movement was simultaneously collected from a computer digitizer tablet. If a sudden body motion (1cm/s) occurred within a time window from one second prior to the onset of the drawing error to the end of the error, we considered that the error coincided with the extraneous body movement. For each drawing trial, the coincidence rate was computed as (number of coincidences)/(number of errors). The ID group had a significantly higher coincidence rate of head and shoulder movements compared with elbow movements, whereas coincidence rates did not differ between the three body parts in the AD group. Parental ratings of children's behavioral ratings of inattention, hyperactivity, and impulsivity were not correlated with the coincidence rates. The results indicated that inaccurate drawing was a result of postural instability rather than fidgeting caused by inattention or hyperactivity/impulsivity.     

The own-age face recognition bias in children and adults

Children recognize children's faces more accurately than adult faces, and adults recognize adult faces more accurately than children's faces (e.g., Anastasi & Rhodes, 2005 Anastasi, J. S. and Rhodes, M. G. 2005. An own-age bias in face recognition for children and older adults. Psychonomic Bulletin and Review, 12: 1043–1047. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). This is the own-age bias. Research has shown that this bias is at least partially based on experience since trainee teachers show less of an own-age bias than do other adults (Harrison & Hole, 2009 Harrison, V. and Hole, G. J. 2009. Evidence for a contact-based explanation of the own-age bias in face recognition. Psychonomic Bulletin & Review, 16: 264–269. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). The present research tested the own-age bias in three groups of children (age 4–6, 7–9, 10–12 years) and a group of adults in the recognition of three age groups of faces (age 7–9, 20–22, and 65–90 years). Results showed an own-age bias for 7- to 9-year-old children and adults. Specifically, children could recognize faces more accurately if they were less than two years different from their own age than if they were more than two years older or younger. These results are discussed in terms of short-term experience with faces creating biases, and this rapidly changes with age.     

The own-age face recognition bias in children and adults

Children recognize children's faces more accurately than adult faces, and adults recognize adult faces more accurately than children's faces (e.g., Anastasi & Rhodes, 2005). This is the own-age bias. Research has shown that this bias is at least partially based on experience since trainee teachers show less of an own-age bias than do other adults (Harrison & Hole, 2009). The present research tested the own-age bias in three groups of children (age 4-6, 7-9, 10-12 years) and a group of adults in the recognition of three age groups of faces (age 7-9, 20-22, and 65-90 years). Results showed an own-age bias for 7- to 9-year-old children and adults. Specifically, children could recognize faces more accurately if they were less than two years different from their own age than if they were more than two years older or younger. These results are discussed in terms of short-term experience with faces creating biases, and this rapidly changes with age.