Triveni Goswami Vernal
Registered Special Educator (CRR A64010)

The first part of this blog provided an overview of Photosensitive Epilepsy and what the triggers for it, might be, whereas the second part of the blog will shed light on Photoparoxysmal Response (PPR) in individuals on the Autism Spectrum.

WHAT IS PHOTOPAROXYSMAL RESPONSE (PPR)?

Photoparoxysmal Response refers to abnormal electrical activity in the brain, that is reflected in an EEG (electroencephalogram), that occurs when the brain is exposed to flashing lights and other visual stimulation.

According to the National Library of Medicine, the Photoparoxysmal Response  has been defined as “the abnormal occurrence of cortical spikes or spike and wave discharges on electroencephalogram (EEG) in response to intermittent light stimulation (Doose and Waltz, 1993)” (accessed from the website https://www.ncbi.nlm.nih.gov/medgen/358382).

WHAT DOES RESEARCH SAY ON PHOTOPAROXYSMAL RESPONSE (PPR) AND AUTISM?
PHOTOPAROXYSMAL RESPONSES IN CHILDREN WITH AUTISM SPECTRUM DISORDERS

Abstract number: 3.109
Submission category: 3. Clinical Neurophysiology
Year : 2011
Submission ID : 15175
Source : http://www.aesnet.org
Presentation date : 12/2/2011 12:00:00 AM, Published date : Oct 4, 2011, 07:57 AM
Authors :
J. Miller-Horn, S. Spence, , M. Takeoka
(Accessed from the website https://aesnet.org/abstractslisting/photoparoxysmal-responses-in-children-with-autism-spectrum-disorders)
The abstract mentioned the following, “This is a pilot study to retrospectively determine the incidence of PPRs elicited during EEG studies in children with ASD at Children s Hospital Boston.Methods: Children with a diagnosis of ASD receiving medical care at Children s Hospital Boston between 12/2010 and 4/2011 were identified through a search of electronic medical records. Of these children, those with an EEG study during or prior to the search period were included in the study. Data was obtained on demographics, including age, gender, and diagnoses of epilepsy. EEG reports were examined to determine the presence or absence of a PPR.Results: The search found 333 children with an ASD diagnosis with an EEG considered, and 206 who had an EEG study… Our study found that in the ASD population, there is an association between the PPR and epilepsy, as has been previously reported in children with epilepsy without ASD. However, when age was taken into consideration, our study found an unexpectedly high rate of 25% overall with a PPR in children with ASD >15 years of age, and an even higher rate of 29.4% (5/17) when excluding children with ASD without epilepsy in that age group”.

CORRELATIONS BETWEEN EEG ABNORMALITIES AND CLINICAL PHENOTYPES IN A POPULATION OF CHILDREN WITH AUTISM SPECTRUM DISORDER

Roberta Ruffini et al
Received 27 August 2023, Revised 15 December 2024, Accepted 13 February 2025, Available online 7 March 2025, Version of Record 7 March 2025.
https://doi.org/10.1016/j.reia.2025.202536
Accessed from the website https://www.sciencedirect.com/science/article/pii/S3050656525000082
The abstract stated the following, “We collected information about patient’s past medical and developmental history and investigated clinical phenotypes using the observation and standardized instruments in a cohort of 111 outpatients with ASD or at risk for ASD. Then we proceeded to investigate the association between EA (EEG Abnormality) and phenotypic characteristics. In our cohort we found a significant frequency (90%) of moderate/severe autism spectrum symptoms (corroborated by results from standardized tests, such as ADOS-2). Epileptiform EA detected in our sample were mainly focal, with a predominantly left fronto-central temporal region localization. Generalized or widespread epileptiform EA during sleep EEG was significantly correlated with non-verbal profile, greater impairment in terms of social interaction, and higher ADI-R scores in the communication and language scale. In the current study, the presence of widespread epileptiform EA correlates with a more severe clinical presentation, in particular with a non-verbal profile and impairment in social interaction. However, it is necessary to understand if EA may be considered an epiphenomenon of the underlying neural dysfunction or whether there is a causal relationship with the autism phenotypes”.

AUTISM, EPILEPSY AND INTELLECTUAL DISABILITY: A CLINICAL CONUNDRUM

Anand, V., Jauhari, P
Editorial Commentary, The Indian Journal of Pediatrics
Published: 31 July 2019
Volume 86, pages 877–878, (2019)
https://doi.org/10.1007/s12098-019-03045-9
Accessed from the website https://link.springer.com/article/10.1007/s12098-019-03045-9
The article stated the following, “Autism and epilepsy are heterogenous disorders of neuronal networking. Both these disorders along with global developmental delay/intellectual disability (GDD/ID) often co-exist in children… The world literature reports that epilepsy may be prevalent in up to a third of children with autism (cited from Lai M-C, Lombardo MV, Baron-Cohen S. Autism. Lancet. 2014;383:896–910). The exact figure however depends upon the diagnostic criteria used for autism spectrum disorder, EEG protocol, age group of cases and prevalence of other co-morbid conditions such as GDD/ID. ..Anukirthiga and colleagues …studied the prevalence of epilepsy and interictal epileptiform discharges in children with autism and Attention deficit hyperactivity disorder (ADHD). The important observations of their study were: (A) A high prevalence of epilepsy in autism (45.5%) and ADHD (37.5%), (B) A strong association of epilepsy in autism with low IQ as well as severity of autism and, (C) A significant proportion of cases who did not have seizures had interictal epileptiform EEG discharges 17/90 (19%) (cited from Anukirthiga B, Mishra D, Pandey S, Juneja M, Sharma N. Prevalence of epilepsy and inter-ictal epileptiform discharges in children with autism and attention-deficit hyperactivity disorder. Indian J Pediatr. 2019). … Photoparoxysmal response in EEG in autism may suggest a diagnosis of Angelman syndrome, late infantile neuronal ceroid lipofuscinosis or SCN1A genetic variation. Identifying these conditions is important as the treatment plan completely differs. Early consideration of antiepileptic drugs, immunomodulation and dietary therapy may be more beneficial”.

The selected research studies mentioned here, do show a correlation between Autism and Photoparoxysmal Responses (PPR), but they are mostly found in individuals who already have a history of seizures. 
Additionally, individuals on the Autism Spectrum can also have a Photoparoxysmal Response (PPR) on an EEG without ever experiencing clinical seizures. It can merely be a sign of Photosensitivity—with the brain getting activated with stimulation from flickering lights and other visual sources.

HOW CAN PHOTOPAROXYSMAL RESPONSE (PPR) WITHOUT A HISTORY OF SEIZURES, IN AUTISM, BE MANAGED?

One can manage PHOTOPAROXYSMAL RESPONSE (PPR) without a history of seizures by bringing about lifestyle changes—avoiding flickering lights, wearing special glasses or taking medications under the supervision of a trained medial practitioner.

*PLEASE NOTE: Always consult a doctor for any medical advice*

REFERENCES:
https://www.ncbi.nlm.nih.gov/medgen/358382
https://www.sciencedirect.com/science/article/pii/S1525505020302250
http://www.eegpedia.org/index.php?title=Photoparoxysmal_response
https://academic.oup.com/brain/article-abstract/130/1/78/346889?redirectedFrom=fulltext
https://www.sciencedirect.com/science/article/pii/S1059131120302740
https://www.epilepsy.com/sites/default/files/2022-10/Epilepsia_2022_fisher_visually_sensitive_seizures.pdf
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Dr.Triveni Goswami Vernal is a Registered Special Educator (CRR: A64010), a Psychologist and an Expressive Arts Therapy Practitioner (UNESCO-CID). She is an Avaz Certified Educator and Certified in Dyslexia Teacher Training. She is also an art educator for children with additional needs. She has a 14 year old on the Autism spectrum. She is presently working as a Consultant Special Educator at Oyster CDC, Begumpet, Hyderabad.

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“Christmas”
Acrylic Painting and Acrylic Marker pens on Ivory Paper
Kabir Vernal