The NPKUA Psychosocial Committee — made up of dedicated mental health practitioners — is excited to share this quarterly update with our PKU community. In each edition, they will explore topics related to mental health, wellness and living with PKU, offering insights, tips and resources to support emotional well-being. Their goal is to foster connection, understanding and resilience within the PKU community, and they hope you find inspiration and encouragement in these pages.
Spotlight on Neuropsychological Evaluations: Insights and Processes for Individuals with PKU
By Arianna Stefanatos, Ph.D. Pediatric Neuropsychologist at Children’s Hospital of Philadelphia and Arianna Martin, Psy.D. Pediatric Neuropsychologist at Children’s Hospital Colorado
Individuals with phenylketonuria (PKU) benefit from several types of monitoring because phenylalanine (Phe) levels can affect both the body and the brain. This is necessary for healthy growth and brain development and to support optimal functioning in everyday life. In addition to regular blood testing and diet monitoring, medical providers may also monitor functioning by asking questions about any challenges in school or work settings or by gathering information from school evaluations. Some providers may suggest pursuing a neuropsychological evaluation. This may not be necessary for everyone with PKU, but this type of testing can provide information about how the brain is working in everyday life. But what is a neuropsychological evaluation, what does it involve, and why is it helpful?
What is a Neuropsychological Evaluation?
Neuropsychology is a special field of clinical psychology that focuses on understanding how the brain affects the way we think, learn, remember, pay attention, and solve problems. Neuropsychologists also explore how a specific medical condition may impact different types of thinking skills or overall social/emotional/behavioral functioning.
To explore how the brain is functioning, neuropsychologists use standardized tests and questionnaires to evaluate different types of thinking skills, such as attention, learning, memory, language, reasoning and problem solving as well as psychological, emotional and behavioral factors. Neuropsychologists then use this information to help identify what types of skills or activities may be easier or harder for the individual in their everyday life.
Neuropsychologists can help answer questions like:
- How well does someone pay attention?
- How strong is their memory?
- How do they learn new information?
- How well can they plan, organize, or solve problems?
- Are there areas where they may need extra support?
Neuropsychological evaluations provide a snapshot of how the brain is working at a certain point in time in the context of potential ongoing medical issues and treatments. Depending on the results, we also recommend interventions or strategies to help the individual in their potential areas of weakness. These can be supports that may be implemented across different types of settings, including at home, school, or work.
Why is this helpful for an individual with PKU?
Understanding more about one’s personal strengths and weaknesses can be helpful for anyone, but it may be especially helpful for individuals with PKU for several reasons.
- Early Identification of Challenges: For many individuals with PKU, things go very well, especially when treatment starts early and is followed consistently. Even so, PKU can sometimes be linked to small challenges that may not show up on school tests or during a short doctor’s visit. Research has shown that some people with PKU may have more difficulty with paying attention, executive functioning (e.g., planning and organizing tasks, switching between tasks), and managing emotions. Some individuals may work a little harder to stay focused, keep information in mind, or complete work quickly. Families may also notice more frustration, tiredness, or stress, which can also affect learning and behavior. Neuropsychological testing helps clarify whether these challenges are present and what supports may be helpful.
- Understanding of Treatment Effects: A neuropsychological evaluation can help doctors understand how PKU-specific factors may be affecting daily functioning. For example, testing may show how changes in Phe levels or how consistently an individual follows their medication, formula, or meal routines affect attention or other thinking skills. Findings of increased attention problems may suggest that treatment changes or more consistent treatment could be helpful. For patients using adjunct therapies (e.g., sapropterin or sepiapterin), testing may show whether better metabolic control is leading to meaningful improvements in daily life, not just better lab results. Repeat testing or well-chosen follow-ups can help track change across life stages or after treatment adjustments.
- Guidance for Intervention: Neuropsychological evaluations help clarify whether difficulties are mostly related to PKU or if another condition like Attention-Deficit/Hyperactivity Disorder (ADHD), anxiety, depression, sleep problems, or a specific learning disorder is contributing. That distinction matters medically because the best support may involve changes to diet or medical treatment, targeted mental health treatment, school supports, or a combination of these approaches based on the person’s individual needs.
What to expect on the day of the evaluation?
A neuropsychological evaluation has several parts.
- How to Prepare: Before the evaluation, it can be helpful to prepare a list of potential questions or concerns that you would like to discuss. It is also helpful to send any previous evaluations, medical, and school records to the neuropsychologist to review before the appointment.
- Clinical Interview: The evaluation typically starts with a discussion with the neuropsychologist about developmental, medical, school/work history, daily routines, and current concerns. In the clinical interview, you can discuss specific questions about thinking skills, learning, or behavior.
- Testing Session: The testing session includes structured cognitive activities, which may involve working on puzzles, looking at pictures, answering questions, and other school-like tasks. The total length of the day is generally dependent on the age and needs of the individual but can span from approximately two to six hours long. Breaks are provided, but testing can still be tiring. For this reason, it is important to get a good night of sleep, eat beforehand, and bring water and snacks. Questionnaires may also be completed by the individual, family members, teachers or others to learn more about attention, behavior, social skills, and emotional functioning across different settings.
- Feedback Session: After the evaluation is completed, the neuropsychologist will share results and recommendations from the evaluation with the individual and/or caregivers. This is an opportunity to discuss the individual’s strengths, areas of difficulty, and next steps for intervention.
- Comprehensive Report: The neuropsychologist will prepare a detailed report that summarizes all this information. The report can be shared with the individual’s medical team, and if needed, with others who may support the individual, such as teachers, school staff, or workplace supervisors.
Where can you obtain a neuropsychological evaluation?
The process of obtaining a neuropsychological evaluation can vary depending on your location, age, reason for testing, and insurance. If someone is interested in scheduling a neuropsychological evaluation, the first step is often to obtain a referral from a member of the medical team. Depending on your location, neuropsychological evaluations may be scheduled in the neuropsychology clinic at a local hospital or academic medical center or through a private practice provider. Because trained neuropsychologists can be difficult to access in some areas, wait times for appointments may be longer than for other medical appointments. It is important to confirm that the provider is a trained neuropsychologist. Some clinics primarily offer psychological or psychoeducational testing that focus on learning disorders, ADHD, and school-based supports, rather than a comprehensive neuropsychological evaluation. While these evaluations can provide valuable information, they may not address medical questions related to PKU in the same depth as a clinical neuropsychological evaluation. Hospital-based neuropsychology services are often particularly helpful for individuals with PKU because the neuropsychologist can typically access the broader medical record and communicate directly with the treating medical team. Factors such as appointment availability, travel, cost, insurance, and wait times can create barriers. If a comprehensive evaluation is not possible, school-based psychoeducational evaluations or educational assessments can still provide some useful information about learning and daily functioning. The best place to start is discussing concerns with your medical team to decide what type of evaluation or support may be most helpful.
Looking Beyond the Numbers
A neuropsychological evaluation is a powerful tool to better understand the impact of PKU on daily thinking and learning. It provides valuable information about thinking skills, learning, and everyday functioning. Neuropsychologists can follow individuals as they grow, monitor development, and provide support as needed. By highlighting both strengths and challenges, neuropsychological evaluations guide care and empower individuals with PKU to achieve their goals and optimal functioning.