Looking but not seeing
What do the results suggest?
General issues with research
The Autistic Spectrum Disorder (ASD) is subclassified into three main classifications: autism, Asperger's syndrome and pervasive developmental disorder - not otherwise specified (PDD-NOS). Autism is a developmental disorder characterized by difficulties with social interaction and communication, as well as the presence of the restricted range of behaviors and interests (DSM-5, 2013). An individual's symptoms can range from mild to severe. Symptoms of autism include non-verbal communication problems, social impairment, delay in spoken language, restricted interests and repetitive and stereotyped movements. Asperger Syndrome is named after Hans Asperger (1906-80), the Austrian psychiatrist who described the condition first in 1944. Asperger syndrome shares many of the symptoms of classic autism but with no delay in either language or cognitive development (IQ ranges from average to very superior). Most have excellent rote memory and musical ability and become intensely interested in one or two subjects, sometimes to the exclusion of other topics. People with Asperger's syndrome tend to be "in their own world" and preoccupied with their own agenda (Stöppler, 2016). Children and adults diagnosed with PDD-NOS are the ones who are on the autistic spectrum disorder but do not fully meet the criteria for another form of ASD such as the autism disorder or Asperger syndrome (Autism speaks, unknown year).
Because the signs and symptoms of ASD are almost entirely behavioral, direct or indirect observation is often being used as a diagnostic instrument. There are differences in gathering data. For example, an Autistic Diagnostic Interview focuses on the individual history to find out about e.g. early language development. However, the Autism Diagnostic Observation Schedule is more reliable because the direct observation offers no need of a third party information. Nonetheless, a combination of approaches (history-taking, interview with children and parents, direct observation) is the most reliable option.
Prior studies have primarly focused on adults, tapping the developmental endpoint of face processing without addressing potential developmental changes resulting from an interaction between pathogenic factors responsible for autism and the effects of atypical social experiences that accumulate from early infancy onwards. The following study "Looking But Not Seeing: Atypical Scanning and Recognition in Faces in Two- and Four-year-old Children with Autism Spectrum Disorder" by K. Chawarska and F. Shic was published in 2009 in the Journal of Autism and Developmental Disorders in december 2009 and examines young children affected by Autistic Spectrum Disorder.
Looking but not seeing
Since the motive of the study was to investigate visual scanning and recognition of faces by two- and four-year-old children with Autism Spectrum Disorder, the scientists questioned two main aspects. Firstly, how face processing in ASD is affected early and what changes with age and further, if deficits in recognition can be associated with imbalanced attention between key facial features. The hypothesis includes that children with ASD would distribute their attention between facial features differently than typically developing children. Additionally, they suggest that these differences would be associated with their performance during the recognition phase of the experiment (Chawarska & Shic, 2009).
Therefore, two diagnostic groups were arranged which were divided into four groups of children of chronological age. The two diagnostic groups were dichotomized into typically developing children (TD, n=30) and children affected by ASD (n=44). Children tested in group Age 1 (two years old) participated in the study at the time of their first diagnosis and those in group Age 2 (four years old) were tested during their follow-up confirmatory visit. To ensure that the subjects have a similar physical foundation, all participating children were born after 32 weeks pregnancy and suffered no major prenatal or perinatal insults and had no known visual or auditory abnormalities (Chawarska & Shic, 2009).
To measure the comprehensive level of functioning in the ASD groups the following four assessments were used. The Social Affective Score is supposed to indicate the degree of autistic symptoms in socialization and communication and is based on ADOS-G Modules 1 and 2. Based on the same modules, the Stereotyped and Repetitive Behavior Score surveys the presence of repetitive behaviors and restricted interests. ADOS-G Module 1 is applied through e.g. response to joint attention, bubble play or imagining a birthday party for children who do not consistently use phrase speech. While ADOS-G Module 2 in particular is used for those who use phrase speech but are not verbally fluent, f.e. make-believe play or description of a picture. The Nonverbal and Verbal Developmental Quotient Score succumb the Mullen Scale. The NDQS is obtained by combining visual reception and fine motor scales while the VDQS is obtained by combining receptive and expressive language scales.
The procedure contains a stimuli that consists of color images of affectively neutral female faces (static images). To examine the spatial distribution of attention, the stimuli were divided into five regions of interests: eyes, mouth, nose, outer (hair, cheeks and forehead) and non-facial (neck, body, background, screen) features. Each session began with a brief video clip to help the child get settled. Subsequently, a five-point eye-tracking calibration procedure was initiated. If necessary, the calibration was repeated until all five calibration points were properly identified. Following the system calibration each child was presented with six trials, with each trial divided into a familiarization and a recognition phase. Each trial consists of a presentation of a stimulus for a pre-determined amount of time of approximately 10 s (familiarization phase) after centering the screen for 1 s. The duration of the familiarization phase varied depending on how long it took a child to accumulate 10 s total of active exploration of the stimulus. Next, the screen converts blank for 1 s and the centering procedure was repeated for the same amount of time, followed by a simultaneous presentation of the familiarized stimulus with a novel stimulus from the same class for 5 s (recognition phase) (Chawarska & Shic, 2009).
Children affected by ASD observed the main sources of information of one's face (eyes and mouth) to a minor degree. During the familiarization phase, group Age 2 with ASD spent less time examining inner facial features than both the TD group Age 1 and 2 as well as the group Age 1 with ASD. In addition, regardless of age, children with ASD spent less time looking at the mouth (Chawarska & Shic, 2009).
During the recognition phase, both two- and four-year-old TD children looked longer at novel faces while older children with ASD spent less time looking at either novel or familiar stimuli compared to the ASD group Age 1. Deficits in recognition can be associated with imbalanced attention between key facial features since children with ASD group Age 1 and 2 spent more time looking anywhere but on the key facial features (Chawarska & Shic, 2009).
The association between familiarization and recognition are differently observed among the TD and ASD group. Its resulting in no significant associations between fixation durations on any regions of interests during familiarization and fixation durations at the novel or familiar stimulus for TD children. However, ASD children who spent more time looking at non-facial features during familiarization were also less likely to look at either the familiar or novel stimulus during recognition phase. Moreover, children who spent more time looking at inner features (eyes, mouth, nose) during familiarization were associated with longer looking at the familiar face during recognition. Hence, the distribution of affection within the inner features had an effect on the recognition measures: children with ASD had a more exclusive focus on the eyes compared to the mouth which was associated with a lower novelty preference (Chawarska & Shic, 2009).
What do the results suggest?
Chawarska's and Shic's hypothesis that children with ASD would distribute their attention between facial features differently than typically developing children accords to the results from the experiment. Compared to age-matched TD controls, young children with ASD focus more on the external facial features and were less effective in encoding facial identity. Further, regardless of age, children with ASD distributed attention between key features of the face (eyes and mouth) differently than their age-matched TD controls. However, there was a difference within the ASD age groups as well. In comparison to the ASD group Age 1, ASD group Age 2 spent more attention to non-inner facial features. Their atypical scanning patterns are associated with limited effectiveness of facial identity encoding (Chawarska & Shic, 2009).
One possible cause for the results might be due to limited experience-dependent specialization in the face processing system which results in an atypical activation pattern in a neural network that typically supports face processing and recognition. Less effective face recognition might be linked with the employment of feature-based rather than holistic face processing strategies, meaning that altered face scanning strategies might be indexed by an abnormal spatial distribution of fixations (Chawarska & Shic, 2009).
At what point do the results offer solution accesses or emphasize further prospective research approaches? Attention to key facial features decreases in older children with ASD. This is possibly signaling a cumulative detrimental effect of atypical social experiences on the development of the face processing system. Accordingly, early difficulties in encoding facial identity observed in two-year-olds are likely to impact their effectiveness as interactive partners and thus, should be targeted for intervention (Chawarska & Shic, 2009). Besides, future research should focus on determining conditions for optimizing face processing in infants and toddlers with ASD. For instance, by allocating more time for processing and promoting less restricted scanning strategies of the key elements of the face.
- Quote paper
- Nathalie Neuberger (Author), 2017, Wissenschaftliche Auseinandersetzung mit der Studie "Looking But Not Seeing" von Chawarska & Shic, 2009, Munich, GRIN Verlag, https://www.grin.com/document/501947