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Talk; Soc & Em

Friday stream 4 Session 14.00 - 15.40 Length 25 minutes

The Interpretation of Emotion From Facial Expression for Children With a Visual Sub-Type of Dyslexia

Greg Robinson and P.R. Whiting

Special Education Centre, University of Newcastle, NSW, Australia scglwr@cc.newcastle.edu.au

Abstract

Investigations of dyslexia have largely focussed on academic failure, but the development of social skills is being increasingly recognised as important. A number of studies have claimed that negative social skills identified in such people might relate to the inability to decode subtle social cues. In particular, facial expression has been identified as critical to the development of social responsiveness, with some studies finding children with learning disabilities/dyslexia were less accurate in interpreting facial emotions. The majority of studies of interpretation of facial expression, however, viewed dyslexia as a unitary condition, and only made comparisons between this group and a group with no learning disabilities. There are almost certainly sub-types, and a separate assessment of these is needed. In particular, people with visual processing disabilities which are sufficient to cause problems in identifying letters and words, may also have problems in interpreting subtle visual cues of facial emotion. This study investigated ability to interpret emotion in facial expression in a visual perceptual sub-type called Irlen Syndrome, which is claimed to have central nervous system origin, with a deficit in the magnocellular visual neurological pathway being implicated. A deficit in this pathway has also been proposed as a possible cause of visual processing problems leading to social misperception. The study assessed children with Irlen Syndrome in comparison to children with learning difficulties/dyslexia not related to visual processing and in comparison to normally achieving peers.

While investigation of people with specific learning disabilities/Dyslexia has largely highlighted the effects on academic achievement, motivation and self image, there is also a need to understand the effects of such disabilities on social skills. The development of social skills is increasingly recognised as important for such people (Semrud-Clikeman & Hynd, 1991; Spafford & Grosser, 1993), and a number of studies have identified that a significant proportion of individuals with learning disabilities/Dyslexia exhibit social problems and have low social status (Baum, Duffelmeyer, & Geelan, 1988; Bickett & Milich, 1990; Bryan, 1998; Haager & Vaughan, 1995; Kuhne & Wiener, 2000; McIntosh, Vaughan, & Zaragoza, 1991; Margalit, 1998; Rock, Fessler, & Church, 1997; Sabornie, 1994; Stone & La Greca, 1990).

These social difficulties have often been considered to be products of school failure (Bruck, 1986; Gever, 1991; Horne, 1982; Maughan, Pickles, Hagell, Rutter, & Yule, 1996; Wilchesky & Reynolds, 1986), or other psychological problems (Bryan, 1998; Parrill-Burnstein, 1981; Rock, Fessler, & Church, 1997). There is also the possibility that cognitive processing deficits which are sufficient to cause problems in academic learning may also cause difficulties in interpreting social events (Bender & Wall, 1994; Holder & Kirkpatrick, 1991; Kavale & Forness, 1996; Pearl, 1987; Reynolds, Elksnin & Brown, 1996; Rock, Fessler, & Church, 1997; Spafford & Grosser, 1993; Tur-Kaspa & Bryan, 1993). It has been claimed that the negative social behaviours identified in people with learning disabilities might relate to the neglect of subtle social cues (Toro, Weissberg, Guare, & Liebenstein, 1990), the inability to effectively decode such cues (Crick & Dodge, 1994; Perlmutter, 1986), or deficits in making social inferences (Bruno, 1991).

In particular facial expression has been identified as critical to the development of social responsiveness (Semrud-Clikeman & Hynd, 1991). Infant development of accurate perceptions of maternal facial expressions is claimed to be important for the development of attachment behaviours and social adequacy (Ainsworth, 1979), and children having difficulties in processing visual-spatial stimuli may have problems understanding the human interactions and expressions necessary for social skill development (Holder & Kirkpatrick, 1991; Kaslow & Cooper, 1978). Perception of minor differences in facial expression are important to the understanding of the intent of others (Holder & Kirkpatrick, 1991), and may lead to deficits in social referencing (Bandura, 1986). A number of studies have suggested that children with learning disabilities are less skilled in interpreting facial expression than normally achieving peers (Axelrod, 1982; Bachara, 1976; Badian, 1983; Holder & Kirkpatrick, 1991).

The studies of interpretation of facial expression cited above, however, viewed learning disability as a unitary disorder, and only made comparisons between this group and a group with no learning disabilities. It is likely that there may be a variety of sub-types in the area of learning disability (Bakker, 1990; Eden, Stein, Wood, & Wood, 1995; Harandek & Rourke, 1994; Kohornen, 1991; Robertson, 2000; Shafrir & Siegel, 1994; Spreen & Haaf, 1986), and separate assessment of such sub-types may be needed to ascertain whether there is a differential impact (Little, 1993).

One sub-type has been identified as having poor visual-spatial problem-solving skills, as well as emotional and interpersonal disturbances (Bender & Golden, 1990; Gross-Tsur, Shalev, Manor, & Amir, 1995; Kohornen, 1991). Rourke (1987, 1988; Rourke & Fuerst, 1991) described this sub-type as a non-verbal learning disability, which included primary deficits in tactile perception, visual perception and accommodation to novel tasks. He claimed this sub-type was particularly prone to internalised socio-emotional problems, such as withdrawal and depression. The ability of this sub-type to interpret facial expression was investigated by Dimitrovski, Spector, Levy-Shiff, and Vakil (1998) who found a non-disabled control group had better interpretive ability than a learning disabled group, and those in the verbal disability sub-group had better interpretive ability than those in the non-verbal disability sub-group. Spafford and Grosser (1993) hypothesised that visual anomalies which can cause poor recognition of complex visual patterns of letters and words may generalise to poor interpretation of the complex visual pattern of postures and gestures involved in body language. Semrud-Clikeman and Hynd (1991), and Shapiro and Gallico (1993) also emphasised that there may be problems in understanding the subtle visual cues of facial expression, as well as in using human expressions.

The concept of a visual-perceptual sub-type of learning disability has recently been highlighted by Irlen (1991a) in her development of the use of coloured filters. She proposed a specific visual-perceptual dysfunction, which has been called Irlen Syndrome, and is considered to be unrelated to skills normally assessed by an optometric examination (Evans, Busby, Jeanes, & Wilkins, 1995; Evans, Wilkins, Brown, Busby, Wingfield, Jeanes, & Bald, 1996). There have been reports of a high familial incidence of symptoms (McLachlan, Yale, & Wilkins, 1993; Robinson, Foreman, & Dear, 1996, 2000; Wilkins & Neary, 1991), which further suggests that Irlen Syndrome may be considered a distinct sub-type of learning disability.

People with Irlen Syndrome report a shadowing and doubling or letters and words while reading, as well as a blurring and movement of print (Irlen, 1991b), and such distortions may generalise to the misperception of subtle differences in facial expression and body language (Spafford and Grosser, 1993). Surveys of children and adults with Irlen Syndrome report a lack of confidence and low self opinion (Irlen & Robinson, 1996; Robinson & Foreman, 1999a; Whiting, Robinson, & Parrot, 1994), which may be in part related to difficulties in interpreting social situations. A large number of controlled studies have also reported increased print clarity and improvement in reading and visual processing when using coloured filters (Croyle, 1998; Lightstone, Lightstone, & Wilkins, 1999; Robinson & Conway, 2000; Solan, Ficarra, Brannan, & Rucker, 1998; Tyrrell, Holland, Dennis, & Wilkins, 1995; Whiting, Robinson, & Parrot, 1994; Wilkins, Lewis Smith, Rowland, & Tweedie, in press), including studies using placebo controls (Jeanes, Busby, Martin, Lewis, Stevenson, Pointon, & Wilkins, 1997; Robinson & Foreman, 1999a; Wilkins, Evans, Brown, Busby, Wingfield, Jeanes, & Bald, 1994; Wilkins & Lewis, 1999) and such improvements may also generalise to improved perception of social situations. There have been reports of increases in perception of ability to cope with school and work tasks and in confidence when using coloured filters (Irlen & Robinson, 1996; Robinson & Conway, 1994, 2000; Robinson & Foreman, 1999b), and while such improvements may relate to increased expectations of academic/workplace success, they may also relate to improved confidence in social situations (Spafford & Grosser, 1993).

The present study aimed to investigate the ability to interpret facial expression in children identified to have Irlen Syndrome. Two research questions were investigated:

1) Does the accuracy of interpretation of facial expressions and time taken to interpret them differ in children with learning disabilities related to visual processing (Irlen Syndrome) when compared to children with other learning disabilities of a non-visual origin, and when compared to normally achieving peers?

2) Are there differences according to age level and sex?

METHOD

Participants

The study involved 69 children aged 8-12, allocated to two sub-groups: 1. Children with learning disabilities related to visual processing (Irlen Syndrome) (n=38). 2. Children with no learning disabilities (n=31). The participants with a learning disability were identified by educational and psychological personnel as having learning difficulties and literacy problems. Many of these children were referred to the Children's Centre, University of Sydney, or the Special Education Centre, University of Newcastle for assessment of learning disabilities/literacy problems. Children with no learning disabilities were recruited from regular school situations, with teacher assessment and school achievement data used as the basis for selection.

Measures

All participants were initially assessed on the following measures:

1. The Scotopic Sensitivity Syndrome - Screening Manual (Irlen, 1991b)

The Screening Manual consists of three sections: i) a questionnaire relating to reading and writing performance, light sensitivity and eye strain; ii) a series of visual tasks, and iii) an assessment of the extent to which performance on these visual tasks and reading is improved by the use of coloured plastic overlays. Only children with a high level of symptoms were included in study group 1. The criteria for high symptoms on the screening manual is a score of 16 or more out of 32 items relating to reading difficulties, strain and fatigue, and a score of 8 or more out of 14 on each of the visual tasks. Students without learning disabilities were screened for Irlen Syndrome using the Group Screening Survey (Wilson & Thomas, 1994). Validity studies by Tyrrell et al. (1997) and Gray (1999) found significant associations between scores on the screening manual and reading achievement. A similar significant association has been found for group screening methods (Robinson, Hopkins, Davies, 1995; Wilkins, Lewis, Smith, Roland, Manning, & Evans, 2000).

2. The Learning Disabilities Diagnostic Inventory (LDDI) (Hammill & Bryant, 1998) This inventory requires the class teacher to rate the child on a series of behaviours in the categories of listening, speaking, reading, writing, mathematics and reasoning. For each behaviour category, there are 15 questions which must be rated on a scale of 1 (frequently) to 9 (rarely). For this study, the reading, writing, mathematics and reasoning categories were used. Test-retest reliability coefficients exceeded 0.8. Inter-rater reliability averaged 97%.

3. The Test of Facial Recognition (Benton, Sivan, Hamsher, Varney, & Spreen, 1994)
In this test, the subject is presented with a single front view photograph of a face and asked to identify it in a display of six front view photographs appearing below the photograph (6 items). This is followed by the presentation of a single front-view photograph of a face with instructions to locate it 3 times from a display of 6 faces. The face is displayed either in front view or three quarter view, with 3 faces being other faces. The short form of the test was used as being more suited to children aged 8-12 who were also being asked to undertake other tests.

4. The Word Attack and Word Identification Sub-tests of the Woodcock Reading Mastery Tests - Revised (Woodcock, 1995)
The word identification sub-test requires the subject to identify isolated words. Initially, there are 3 words on a page, but this increases to 9 on a page. The word attack test measures the ability to use phonic and structural analysis to pronounce words which are nonsense words (letter combinations that could be but are not actual English words), or words used very infrequently in English. There are initially 2 words on a page, but this increases to 6 on a page. Split-half reliability for Word Identification is reported between .91 and .97 and for Word Attack, .89-.91.

5. Pictures of Facial Affect (Ekman & Friesen, 1976)

The test consists of 110 35mm black and white slides of adult male and female faces expressing the emotions of fear, sadness, surprise, anger, happiness and disgust, with the subject having to identify the required emotion. Ekman and Friesen (1976) reported interjudgement agreement ranging from 70% to 100%, and Safer (1981) reported interjudgement agreement as 89.2% for males and 91.9% for females. Holder and Kirkpatrick (1991) used a subset of 36 slides to accommodate the likely abbreviated attention spans of children with learning disabilities and cited Ekman, a co-developer of the instrument, as suggesting that a subset of 36 slides would maintain the validity of the instrument. In this study, the original 110 slide presentations was reduced to 48 in order to accommodate the likely shortened attention spans of younger children, especially those with learning disabilities. The 48 pictures chosen (4 male and 4 female for each of the 6 emotions) were those within each category reported by Ekman and Friesen (1976) to have the highest interjudge agreement. In order to reduce the effects of variables such as poor reading and poor test taking on the test score, the instrument was administered individually, as photographs rather than slides, and with participants' responses recorded by the examiner rather than using the standard multiple choice answer sheets.

It has been claimed that the use of photographs with preselected, posed facial expressions, forced choice responses and lack of contextual information (with its access to multiple dynamic cues), challenges the ecological validity of assessment of emotions (Russell, 1994). Bryan (1998), however, emphasises that in real-life situations, social cues are often subtle and only available for very short periods of time. These cues may also be contradicting or confusing. Bryan (1998) argues that interpreting facial cues in photographs may be easier than interpreting non-verbal cues in real-life situations and thus group differences identified in studies of facial affect using photographs are likely to be maintained in the more complex real-life tasks. He also emphasises that studies using more realistic presentations, including videos and social scenarios, have obtained similar results to studies using photographs.

Procedures

Participants who were initially identified as having a learning disability by educational and psychological personnel were assessed with the Scotopic Sensitivity Syndrome Screening Manual (Irlen, 1991b) to identify whether there were visual processing problems. All participants with symptoms of Scotopic Sensitivity/Irlen Syndrome were then assessed for Facial Recognition (Benton et al., 1983), Word Attack and Word Identification (Woodcock, 1995), and Facial Affect (Ekman & Friesen, 1976). The LDDI was completed by each child's regular class teacher.

Children within regular schools who were identified as not having a learning disability were also screened with the Irlen Syndrome Group Screening Test to confirm that there were no visual processing problems. Any participants with a score indicating moderate symptoms or above were excluded from the study. Once this sub-group was identified, they were assessed on the same measures as the experimental group, and in the same order. If any of these participants showed signs of a learning disability, as indicated by a stanine of 6 or below on the LDDI, they were excluded from the study.

Re-testing on all measures (except the Irlen Syndrome Screening Manual and the LDDI) occurred 3 months after the initial test administration. For the experimental group, this re-testing at 3 months ensured that they had received and used their appropriate coloured filters for at least two months.

Analysis

The data will be examined to determine:

1. the relationship between learning disability and interpretation of facial affect;
2. the effect of sex on interpretation of facial affect;
3. the relationship between ability to interpret facial affect and word recognition/word attack skills.

RESULTS

Participants in the study were primary school students aged between 8 and 12 years. The ages of the participants in the Irlen Syndrome group and the Control (non-LD) group are in Table 1. Though the groups were in geographically different locations, they appeared to be comparable in respect of age.

Table 1: Means and Standard Deviations for age (in years and months) for Irlen Syndrome and Control groups

Pretest Results

Facial Recognition

The groups differed in results for Facial Recognition as shown in Table 2:

Table 2: Means and Standard Deviations for scores in Face Recognition for Irlen Syndrome and Control groups

There were no significant differences in scores between males and females.

Reading Performance

The groups also differed in results for both reading tests. In each case, differences were large, as shown in Tables 3 and 4:

Table 3: Means and Standard Deviations for Reading age (in years and months) for Word Identification for Irlen Syndrome and Control groups

Table 4: Mean and Standard Deviation for Reading age (in years and months) in Word Attack for Irlen Syndrome and Control groups

Recognition of Facial Affect

Groups also differed in results for the Recognition of Facial Affect Test, as shown in Table 5:

Table 5: Means and Standard Deviations for score and time (in seconds) in Facial Affect Test for Irlen Syndrome and Control groups

There was an inverse correlation between score and time taken for the Test of Facial Affect (r=.52, p<.001). This suggests that there is a moderate relationship between the two, with participants who took longer to complete the test achieving poorer results overall. There were no significant differences in scores for number correct between males and females.

For each variable, effect sizes were calculated according to Cohen (1992). Table 6 shows the effect sizes for each variable. An effect size of .8 is considered large. All effect sizes were large in this study.

Table 6: Comparison of means in Face Recognition Test, Word Identification Test, Word Attack Test, and Face Affect Test

DISCUSSION

The finding of significant differences in scores for interpretation of facial affect between a group with learning disabilities related to visual processing and a control group confirms previous results obtained by Dimitrovski et al. (1998) and Holder and Kirkpatrick (1991). These findings support the claims by Rourke (Rourke, 1987, 1988; Rourke & Fuerst, 1991), as well as others (Kohornen, 1991; Gross-Tsur et al., 1995; Spafford & Grosser, 1993), that children with a non-verbal/visual processing type of learning disability are more likely to have difficulties in social interaction, especially with interpretation of subtle visual cues critical to understanding social events. Given the critical importance of interpreting facial cues in any social interaction, these results suggest that children with visual processing problems are likely to be particularly disadvantaged, although it must be remembered that a number of social information processing variables are needed to account for social behaviour (Crick & Dodge, 1994).

It could be hypothesised that some form of central nervous system dysfunction causing visual processing problems may lead to impaired communication, resulting in a lowered self-concept and poor social interaction. Peer relationships are very important to child development (Bryan, 1998), with classroom interactions between teachers, students and their peers having a significant influence on academic progress (Kershner, 1990). The usual diagnostic batteries for children with a learning disability or Dyslexia do not include assessment of social skills. To limit assessment of school learning problems to difficulties in literacy and mathematics ignores the importance of social interactions and reduces the possibility that we will effectively help such children or fully understand the nature of their problems. Intervention programs for such children usually concentrate on academic skill building rather than on the development of social skills, and yet longitudinal evidence suggests a link between significant social and workplace problems in later life and social adjustment in childhood (Minskoff, Sautter, Hoffman, & Hawks, 1987; Parker & Asher, 1987; White, 1985).

The finding that children with learning disabilities/Dyslexia have difficulty interpreting emotion from facial expression is parallelled by findings in a variety of other areas of disability. Hobson (1986, 1991) found that children with Autism were significantly less proficient at recognising facial expression or emotionally expressive gestures. Davies, Bishop, Manstead, and Tantam (1994) found a similar significant difference in processing facial stimuli which was hypothesised to reflect a general perceptual deficit. Celani, Battacchi, and Arcidiacono (1999) found such children were significantly worse at perceiving emotional expression in faces than a group with Down Syndrome and a group with normal development, while Schultz (2000) used functional Magnetic Resonance Imaging to assess the neural organisation of people with Autism and concluded that they perceive faces as if they were objects.

There is also a substantial amount of evidence to suggest that people with Schizophrenia have difficulty processing facial expressions and recognising facial emotions (Borod, Martin, Alpert, Brozgold, & Welkowitz, 1993; Cramer, Weegmann, & O'Neill, 1989; Mandal, Pandey, & Prasad, 1998; Schneider, Gur, Gur, & Shtasel, 1995). Recent evidence suggests this may be caused by a disturbance in visuospatial processing of facial emotions (Streit, Wolwer, & Gaebel, 1997), and neurocognitive difficulties (Kee, Kern, & Green, 1998).

Problems with social interaction have also been identified in one sub-group of children with Attention Deficit Hyperactivity Disorder (ADHD). Kinsbourne (1991) identified a sub-group who he called "overfocussed" because they become "stuck" or overly focussed on certain activities. Among the characteristics he identified for this group was difficulty reading non-verbal cues such as faces. Other studies have identified a significantly lower social and emotional functioning in adolescents with ADHD when compared to their non-disordered peers (Lufi & Parish-Plass, 1995; Wilson & Marcotte, 1996). Tracey and Gleeson (1998) found adolescents with ADHD reported significantly less concern about others' feelings and about relationships with others than did non-disordered adolescents.

The findings of difficulties in social interaction and interpretation of facial expression in a variety of diagnostic categories raises the question of overlap in current disability terminology. Broad diagnostic categories currently in use, such as Dyslexia, Autism, ADHD, and Schizophrenia could include overlapping clinical disorders, which may cause confusion about diagnosis and appropriate treatment. The visual processing difficulties which cause problems in interpreting facial affect for people with learning disabilities may have a similar causal basis for difficulties in interpreting facial expression in people with Autism and Schizophrenia and for one sub-group of people with ADHD.

The possibility of overlapping diagnostic categories has been put forward by a number of authors (Anderson, 1997; Cohen, 1994). In particular, it has been claimed that there is a substantial overlap in the diagnostic categories of learning disability and ADHD (Parry, 1996; Reynolds, Elksnin, & Brown, 1996), with the possibility that they have a common neurological or genetic influence (Hay & Levy, 1996). Cade, Privette, Fregly, Rowland, Sun, Zele, Wagemaker, and Edelstein (2000) found similar patterns of peptide abnormalities in people with Autism and Schizophrenia, with a diet free of gluten and casein, or dialysis plus a diet free of gluten and casein, leading to a decrease in these peptide abnormalities and to improvements in clinical behaviour. These results led to speculation by the authors that both disorders may be due to the same basic deficit. A number of studies have also found abnormalities with smooth pursuit eye movements in people with Schizophrenia (Abel, Levin, & Holzman, 1992; Radant & Hommer, 1992; Ross, Olincy, Harris, Sullivan, & Radant, 2000), with a restricted visual scanning style across faces (Kurachi, Matusi, Kiba, Suzuki, Tsunoda, & Yamaguchi, 1994; Streit, Wolwer, & Gaebel, 1997), and similar eye movement problems are frequently reported in people with Irlen Syndrome (Fletcher & Martinez, 1994; Robinson & Foreman, 1999b; Solan et al., 1998; Tyrrell, Holland, Dennis, & Wilkins, 1995).

There is a need to look at the complex and confusing ways in which learning disabilities, attention problems and affective disorders may interact. One disability may look like another, a primary disorder in one area may lead to problems in another area, or a person may have a significant disorder in a number of areas. This confusion may be moderated if sub-categories, such as visual processing disability, are identified across a range of currently used broad diagnostic entities. If people with visual processing problems are clearly identified, they could possibly be targeted as being at greater risk of developing personal and social problems, with more emphasis being placed on this area in their individualised intervention program.

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