It is still unknown which bio-chemical mechanisms lead to the occurrence of West syndrome. It is conjectured that it is a malfunction of neurotransmitter function, or more precisely, a malfunction in the regulation of the GABA transmission process. Another possibility being researched is a hyper-production of the Corticotropin-releasing hormone (CRH). It is possible that more than one factor is involved. Both hypotheses are supported by the effect of certain medications used to treat West syndrome. Cases of epilepsy have been historically divided into three different groups: symptomatic, cryptogenic, and unknown. The International League Against Epilepsy (ILAE) recommended in 2011 to abandon these terms for reasons of clarity and instead try to place individual cases into one of the following 3 groups: genetic, structural/metabolic, and unknown. The new terms are more immediately clear in their meaning, except that the structural and metabolic group includes cases that have a genetic component that does not always directly lead to the condition. Only the genetic grouping has a known direct genetic cause. "Unknown" cases may be of unknown genetic, structural, metabolic, or other unknown cause. The old terminology was defined by the ILAE as follows: * symptomatic: the epilepsy is the consequence of a known or suspected disorder of the central nervous system. * cryptogenic: this refers to a disorder whose cause is hidden or occult. Cryptogenic epilepsies are presumed to be symptomatic. * idiopathic: there is no underlying cause other than a possible hereditary predisposition. The remainder of this section will refer to the older terminology. Symptomatic If a cause presents itself, the syndrome is referred to as symptomatic West syndrome, as the attacks manifest as a symptom of another problem. Almost any cause of brain damage could be associated, and these are divided into prenatal, perinatal, and post-natal. The following is a partial list: * In around one third of the children, there is evidence of a profound organic disorder of the brain. This includes: * microcephaly * cortical dysplasia * cerebral atrophy * lissencephaly * bacterial meningitis * phakomatoses (e.g. tuberous sclerosis) * Aicardi syndrome * cephalhematoma and * vascular malformation. * Furthermore, other causes increasingly being named in the literature are: * Incontinentia pigmenti * Foix-Chavany-Marie syndrome * Patau syndrome (trisomy 13) * Sturge-Weber syndrome * neurometabolic diseases * congential infections (e.g. Cytomegalovirus) * hypoglycemia * brain damage due to asphyxiation or hypoxia (lack of oxygen, e.g. during birth), periventricular leukomalacia, cephalhematoma, cerebrovascular accident or brain damage of various types as well as that caused by premature birth. Down syndrome West syndrome appears in 1% to 5% of infants with Down syndrome. This form of epilepsy is relatively difficult to treat in children who do not have the chromosomal abnormalities involved in Down syndrome. However, in children with Down syndrome, the syndrome is often far more mild, and the children often react better to medication. The German Down Syndrom InfoCenter noted in 2003 that what was normally a serious epilepsy was in such cases often a relatively benign one. EEG records for children with Down syndrome are often more symmetrical with fewer unusual findings. Although not all children can become entirely free from attacks with medication, children with Down syndrome are less likely to go on to develop Lennox-Gastaut syndrome or other forms of epilepsy than those without additional hereditary material on the 21st chromosome. The reason why it is easier to treat children with Down syndrome is not known. If, however, a child with Down syndrome has seizures that are difficult to control, the child should be assessed for autistic spectrum disorder. Cryptogenic When a direct cause cannot be determined but the child has other neurological disorder, the case is referred to as cryptogenic West syndrome. The cryptogenic group is often considered idiopathic while referred to as "cryptogenic". Sometimes multiple children within the same family develop West syndrome. In this case, it is also referred to as cryptogenic, in which genetic and sometimes hereditary influences play a role. There are known cases in which West syndrome appears in successive generations in boys; this has to do with X-chromosomal heredity. Genetic Mutations in several genes have been associated with West syndrome. These include the Aristaless related homeobox (ARX) and cyclin dependent kinase like 5 (CDKL5) genes. The ARX gene in particular seems to be responsible for at least some of the X linked cases. Variants in the KCNT1 gene (also known as SLACK potassium ion channel gene) can result in West syndrome https://www.ncbi.nlm.nih.gov/books/NBK525917/ Idiopathic Occasionally the syndrome is referred to as idiopathic West syndrome, when a cause cannot be determined. Important diagnostic criteria are: * Regular development until the onset of the attacks or before the beginning of the therapy * no pathological findings in neurological or neuroradiological studies * no evidence of a trigger for the<unk>  Those are becoming rare due to modern medicine.
Epileptic spasms
Gelastic seizure
Reflex seizure
Musicogenic seizure
Hair-grooming syncope
Benign neonatal sleep myoclonus
Reflex syncope
Absence seizure