Cognition and Behaviour

Cognition

TCF4 is necessary for the development of the nervous system and it plays an important role in cognition (learning) and behaviour. Children and adults with PTHS often have problems with filtering the stimuli coming from outside their body and within. If parents and caregivers manage to make the environment quieter (‘filtering’) the children and adults will more easily get the really relevant information, are no longer overloaded with information, and often have less behavioural problems as well.

Identifying suitable assessment tools for the PTHS population is difficult. Still, all with PTHS in publications show moderate to severe intellectual disability. In most reported people with PTHS their developmental ages range from 9 to 36 months (mean 14 to 16 months). A mild cognitive delay has been reported in some, but they had unusual changes in the gene but when assessed more carefully it is clear they do not have PTHS.

People with PTHS have mild to severe motor learning problems like with rolling, sitting and walking, and often make repeated movements such as hand clapping and flapping, repeated hand to mouth movements, head shaking, head banging, body rocking, washing, finger crossing, and rubbing toes together. Motor milestones and self-care skills like feeding themselves are delayed (see Section 10). Very few learn to dress themselves or use the toilet on their own. It has been seen that many can help with dressing, like unzipping their coats. Skills can continue to develop as they get older. In very few older people this ability was lost. Once someone is diagnosed with PTHS, they should have developmental assessments to work out the services and educational solutions they need to help with their development (see also section 10) (R33).

Language and communication

Children and adults with PTHS usually have problems with recalling words and language development. Most do not learn to speak. Just over a half will say single words before the age of 10, but many will have no speech at all their whole life (R34). Everyone with PTHS should be assessed for the best communication options to them (R35). 

Speech therapy including access to augmentative and alternative communication (AAC) should be considered. 

Other areas to consider for input are special education services focussing on the development of life skills and help aimed at changing behaviour such as self-harming and anxiety (R36). 

Physiotherapy and occupational therapy are recommended for the development of motor coordination, with the goal that a child can carry out an intended movement like picking up a toy. 

When a child is being assessed for communication and language abilities all aspects including motor abilities should be taken into account.

Behaviour

Most children with PTHS are described as friendly and show lovable behaviours, but many will also pull hair, have temper tantrums, throwing their arms and legs out, and banging on or throwing or kicking objects. Half are described as having a smiley appearance. 

Self-harming such as pinching, pressing, and hitting themselves is seen, as well as problems connecting with others. Other behaviours are anxiety, distress, repetitive actions, and autism spectrum disorder (ASD). 

Problems in filtering and processing sensory input like bright lights increase the risk of under- or overstimulation and can lead to inappropriate behaviours eg head shaking. However, there is evidence that some children’s mood is improved by music as they enjoy it. Children and adults with PTHS need a sensory processing assessment to help work out what to avoid or to introduce to prevent under- and/or overstimulation (R37).

Anxiety and agitation

More than one-third of people with PTHS have anxious, agitated and/or aggressive behaviours. This may be due to frustration in not being able to communicate (R38). Unrecognized pain or other sensory or body issues may cause these behaviours. Aggression and shouting are often associated with changes in routine. The start of puberty can increase these behaviours.

Repetitive behaviours and stereotypies

Most with PTHS studied show repeated movements eg flapping, twisting body movements or flicking hands or fingers. This can be seen in the way they hold objects like toys eg turning over in the hand and being fascinated by certain objects. These repeated behaviours may become stronger when they are anxious or when they are not able to get away from situations like a room with loud music.

Autism spectrum disorder

It is common for children with PTHS to have a lack or reduced social and communication interaction skills along with repeated behaviour patterns, such as hand clapping and flapping, head banging, body rocking, or finger movements. They are also likely to have less adaptive skills Often the lack of skills cannot be explained by the degree of their intellectual disability. Therefore, careful observation of behaviour including autism-specific assessments are warranted. If ASD is present as a separate diagnosis, next to PTHS, this is helpful in caring for someone with PTHS, for instance by preventing overstimulating and/or under-stimulating (R39).

Pharmacotherapy (use of medications)

Persistent problematic behaviour like self-harming can be very distressing and therefore needs to be treated. 

It should first be considered if there are some physical, mental, and environmental issues that are leading to the problematic behaviour This should be by careful assessments and solutions should be looked for by changes in the environment such as softer lighting, and behavioural therapy. 

If these solutions are not enough, medication should be considered. There is not much scientific proof that psychotropic medication is effective in children with PTHS, and there have been no controlled studies. Still, in a survey on medication during the PTHS World Conference 28 families gave their experience on different types of medication and their effects and side effects. 

Melatonin and/or gabapentin was used for sleep problems, methylphenidate and clonidine were used for irritability, agitation and hyperactivity, and lorazepam had been used for agitation. Antipsychotic agents, pipamperon and promethazine, were used to help with challenging behaviour. These antipsychotics should be carefully monitored, evidence for effectiveness is limited and long-term use may result in significant harmful effects such as weight gain, high blood pressure and diabetes. Overall, parents reported satisfaction with medications prescribed and noted few significant side effects, but no single medication was found to be extraordinarily effective. 

In general prescriptions should start at low doses and gradually give more or less medication, in a slow way, to obtain the best effectiveness. One should monitor health before starting and while giving medications, and consider from time to time if stopping of continuing medication is useful. One should ask for the opinions of the caregivers on the effects of medications (R40).