What is Autism Autism also known as Autism

What is Autism? Autism, also known as Autism Spectrum Disorder (ASD) is a Pervasive Developmental Disorder (PDD) which includes impairments in social interaction, language delay, repetitive or ritualistic behaviors, abnormal attachment to objects or events and abnormal reactions to sensory stimuli. ASD is usually diagnosed around 3 years of age. (DSM IV 1994) 2

Hyper- and Hyposensitivity l l Individuals with Autism are often hyper- or hyposensitive to stimuli and often exhibit odd responses to sensations. Typically, individuals diagnosed with Autism exhibit a high tolerance for pain and hypersensitivities to light, noise, touch and odors. However, some clinicians believe the odd behaviors exhibited in response to bright lights, loud noises or certain textures are actually pain responses. For example, when taken into a noisy auditorium, a young boy diagnosed with Autism covered his ears immediately and started screaming! Why? (Kern et. al. 2002) 3

Typical sensory processing problems documented in children diagnosed with Autism l l l l Tactile defensiveness – characterized by hypersensitivity to touch and textures An child may refuse to wear clothing made from certain types of materials or avoid being touched or bathed. Oral defensiveness – characterized by hypersensitivities to foods and food textures Often this is exhibited by the child’s extremely restricted diet. Visual defensiveness – characterized by over sensitivity to light A child may refuse to be in a lighted room or cover his or her eyes in the sunlight. Auditory defensiveness – characterized by a hypersensitivity to sound The child may cover his or her ears when the radio is turned on or when entering a noisy environment. (Kern et. al. 2002) 4

Pain Reactivity l l 1. 2. 3. 4. l l Militerni et. al. studied pain reactivity in children with Autism and related the findings to serotoninemia (serotonin blood levels). Children chosen for the study met the following criteria: Diagnosis of Autism made on the basis of the DSM-IV criteria Absence of other disorders such as Down Syndrome, Muscular Dystrophy or Fragile X Syndrome. Absence of complex epileptic syndrome. Under 11 years of age. A total of 77 children were chosen (63 boys and 12 girls between the ages of 2. 5 and 10. 7 years of age) The study also included a control group of 32 nonautistic children, matched for age, gender and socio-economic class. (Milterni et. al. 2000) 5

Clinical Evaluation l l 1. 2. 3. Cognitive development scales, adaptive behavior scales, direct observation, EEG, and brain imaging, were used in the initial assessment. Reports of the child’s behavior were obtained through a structured interview with the parents. (Often children diagnosed with Autism are nonverbal or have limited communication skills. ) If a parent reported an abnormal reaction to nociceptive stimuli, the interviewer asked a series of follow-up questions. The follow-up questions were designed to obtain information about the frequency of the abnormal reactions, the kind of stimuli in which the child showed analgesia and the environment in which the reaction occurred. The behaviors reported by parents were coded into the following categories: Normal pain response – no abnormal reaction were described Low pain response – abnormal reaction to pain was discontinuous or related to a particular stimulus or situation Very low pain reactivity – abnormal reaction were constant regardless of the kind of stimulus and situation (Militerni et. al. 2000) 6

Results l l l The pain reactivity was low in 22% and very low in 21% compared to 7% (low) and 3% (very low) in the control group. For the autistic group, the relationship between pain reactivity and age, cognitive development, and adaptive behavior scores showed no significant correlation. However, a statistically significant finding was seen in the blood serotonin levels between the normal pain reactivity group and the very low pain reactivity group (lower serotonin blood levels). (Militerni et. al. 2000) 7

Potential Problems l l l The study is based on parents’ interpretations rather than verbal communication of pain thresholds by the child. The communication barrier does not allow for checklists or self-report! The faces pain scale is also useless because children diagnosed with Autism typically have a difficult time distinguishing between depictions of emotions. Nevertheless the correlation between serotonin blood levels and Autism have not been reported in any other studies regarding Autism. (Militerni et. al. 2000) 8

Abnormalities of the Cerebellum l l 1. 2. 3. 4. Abnormalities of the cerebellum have been documented most consistently by both autopsy and MRI when studying individuals diagnosed with Autism (adult and adolescent brains). Abnormalities include: Ritvo et. al. found a loss of Purkinje cells (15 standard deviation below the mean) in the “vermis or midsection of the cerebellum and the hemispheres” (8 standard deviations below the mean) Purkinje cells are GABAergic neurons (inhibitory); however, they release endocannabinoids that modulate both excitatory and inhibitory synapses. Kemper and Bauman found pathology in all of the cerebellar nuclei of the cerebellum which areas that receive afferents from the Purkinje cells and project efferent to the rest of the nervous system. Courchesne et. al. found problems in lobes VI and VII of the cerebellum which areas that receive significant auditory and visual input. Granule cell loss – Granule cells refer to tiny neurons that are found in the granular layer of the cerebellum and account for nearly half of the neurons in the CNS. They receive excitatory input and branch out to synapse with Purkinje cells. (Kern et. al. 2002) 9

Sensory Discrimination And The Cerebellum l l The cerebellum has generally been associated with motor functioning, however, research suggests that the cerebellum is engaged in sensory acquisition and sensory discrimination and is used to help us explore and understand our world. Crispino and Bullock showed clear evidence of a sensory role of the cerebellum in modulating afferent sensory input to other parts of the brain. They showed that the cerebellum particularly the vermis area enhance or depresses auditory, somatosensory and visual sensory input. (Kern et. al. 2002) 10

Results From Cerebellum Studies l l When individuals under respond to sensory stimuli it may be a result of depressions of sensory afferents when there should be none. When persons over respond or seem over whelmed (look as though they are in pain) with certain stimuli this may be because sensory afferents are enhanced when they should not be. There may be an inconsistency in the intensity of modulation of sensory information. In addition, there is a possibility that multisensory information is not being processed or integrated properly. The control over sensory acquisition could be variable, poorly modulated and or inconsistent and thus the world could be uncomfortable (painful), confusing and difficult to interpret. (Kern et. al. 2002) 11

Treatment Because the way we perceive and integrate sensory input effects how we respond and relate to our environment, it is important to understand ways of helping the child integrate sensory input more efficiently and effectively. l Sensory Integration Therapy (SI) l Auditory Integration Training (AIT) l 12

Sensory Integration Therapy l l Hyper- and Hypo- sensory responses are thought to reflect poor sensory integration and/ or arousal modulation in the central nervous system, although the underlying nature of these symptoms remain speculative (neurological structure such as the cerebellum, limbic system, cortical mechanisms). Sensory integration (SI) therapy is based on the work of Dr. A Jean Ayres and is intended to focus directly on the neurological processing of sensory information. Disruptions in subcortical functions are treated by providing controlled therapeutically designed sensory experiences for a child to respond to with adaptive motor actions. Through somatosensory and vestibular activities actively controlled by the child, the nervous system is thought to be able to better modulate, organize, and integrate information from the environment, which in turn provides a foundation for further experiences and responses. Usually provided in a 1: 1 setting by an Occupational Therapist 1 -3 times a week. (Baranek 2002) 13

Treatment Goals l Treatment goals may center on improving sensory processing to either (a) develop better sensory modulation as related to attention and behavioral control or (b) integrate sensory information to form better “perceptual schemas and practice abilities as a precursor for academic skills, social interactions or more independent functioning”. (Baranek 2002) 14

SI Therapy Room 15

Hypersensitivity To Light Therapy Room 16

Auditory Integration Therapy l l AIT was originally developed to treat auditory dysfunctions; however, it has been used recently to treat hypersensitivities to sounds in children with Autism. Individuals diagnosed with Autism may be hypersensitive to certain frequencies of sound. For example, one individual might be hypersensitive to the frequencies of 1, 000 and 8, 000 Hertz while perception of all other frequencies falls within the normal range. In this case, the individual might become over stimulated, disoriented or agitated in the presence of sounds at 1, 000 and 8, 000 Hertz. Another consideration is that an individual's hearing might be asymmetrical (significantly different between the two ears). When the right and left ears perceive sounds in an extremely different way, problems with sound discrimination can occur. During Auditory Integration Training, music is sent through a specialized electronic device. The electronic device randomizes and filters the frequencies from the music source and sends these modified sounds into the child's ears through a set of headphones. The randomized frequencies mobilize and exercise the inner ear and brain. For example, the sound waves vibrate and exercise the muscles that control the three ossicles (the small bones in the middle ear). 17

AIT Therapy Session l A total of twenty 30 minute sessions are required. The sessions are usually stretched over one month. 18

Reported Improvements Improvement in language discrimination and comprehension l Reduction of “hyper-acute/painful hearing” l Less complaints of sounds causing pain or discomfort l Less startle responses to loud noises l Less irritability l 19

Conclusion l l We are not sure why children diagnosed with Autism are hypersensitive to some stimuli and hyposensitive to others. Are light, sound, touch… painful? Current treatments are not scientifically proven or contain faults in research supporting there use (small sample size, no control group, rely on parent statements of improvements rather than analysis). More research in this area would lead to better treatment outcomes! 20