What Types of Memory Impairments are There in Children?

Patient Presentation
A 15-year-old male came to clinic with a history of head injury from a soccer game 8 days previously. He had no loss of consciousness and sat out the rest of the practice. He continued to have a headache for about 48 hours which then resolved. He reported being more tired but this continued to improve over time. He had returned to school and did return to play after 4 days. He denied any problems with gross motor movements including having no balance issues or vertigo. He had no problems with lights or sounds. He said that he was doing his homework but that he seemed to be taking longer to do. He was having more problems learning information since the head injury. “I get most of it, but school used to be easy, and now I have to work. It took me a lot longer to learn my Spanish vocabulary this week and usually I’m right on top of my math. I study it and get it during class, but seem to forget it by the night and study it again. Then in the morning I can remember most but not all of it. I feel foggy,” he explained. When asking about how he had felt right after the accident, he stated, “I think it was the same, but I my head was hurting and I was so tired. I guess I thought about them more. I’m having some problems doing what my coach also just asks me to do in practice too.” His mother said that she had noticed that he seemed less organized and didn’t seem to remember various things he needed to do or schedules. She also said he seemed “a little fuzzy” to her as well. “I asked his friends and they thought he was fine. Also a friend of mine also is one of his teachers and she said he seemed to be doing okay at school, so I thought it was okay for him to go back to practice,” she offered. The past medical history showed no reported head trauma, learning problems or attentional problems.

The pertinent physical exam revealed a thin but muscular teen with normal vital signs. His examination was normal. His SCAT 3 head injury assessment was normal except for delayed recall of only 2 of 5 words, and he could do 4 digits forwards and 3 digits backward for concentration.

The diagnosis of head concussion with memory and concentration problems was made. The patient’s clinical course showed that cognitive rest for a week was recommended and at followup he and his father reported that he was acting normally and now was not having memory or concentration issues. His SCAT 3 assessment was entirely normal. He followed the return to play concussion plan and at his next appointment said that all had gone well. He continued to participate in high school and recreational league soccer.

Discussion
Memory is an important part of what distinguishes higher order species from others. Memory also is part of one’s self-identity. Difficulties in short-term memory can make common, everyday tasks difficult for the person experiencing the problem particularly if it recently occurred and the person’s long-term memory is intact. Difficulties with long-term memory can also have problems when language, events or even one’s own identity are affected. For some people the memory loss is temporary but for others, memory impairments are permanent and must be accepted and accommodated as part of the overall person. Many people have relatively minor problems that they work with every day which are not disabling (always has a hard time finding a word, or planning details), but others have more severe problems which can be a disability for them.

Head injury can be a common, acquired cause of memory problems which maybe temporary or permanent. Amnesia of the event is quite common. Concussive symptoms often last longer in children and teens than in adults, and it is also not uncommon for new symptoms to occur after the initial time period. A review can be found here.

Learning Point

  • Short-term memory (STM)
    • Also called immediate memory or working memory
    • STM “…hold[s] current perceived or retrieved information in an active and conscious format during the completion of a cognitive task.”
    • STM “…integrate[s] current information with the immediate past and the immediate future and hence is a critical function for maintaining internal thoughts and activated cognitive representations synchronized with ongoing external events.”
    • Examples: holding the successive results of a mental math calculation in one’s head to then use in the next step such as adding 4 numbers together, remembering a new word one has just heard before starting to repeat it orally or in one’s head, maintaining the picture of something that needs to be copied
    • Impairment: immediate impairment of verbal sequences (such as digit recall) or visuospatial patterns (such as copying).
    • Impairment causes: head injury, stroke, genetic syndromes such as Down, Kleinfelter, Turner, Velo-cardio-facial, Williams syndromes. It is also associated with other broader cognitive problems such as aphasia or dyslexia.
    • Brain areas affected: inferior parietal lobe and/or interior front gyrus
    • Treatment: treat underlying cause if possible, use “work arounds” such as computer/paper/pen to write down information, calculator, spell checker, etc.
    • STM Subcategories
      • Verbal – difficulty maintaining or using new words/language
      • Order – difficulty maintaining order of events
      • Visual – difficulty with mental imagery or new visual information
  • Long-term
    • Episodic long-term memory
      • Episodic memory “allows the encoding, storage, and retrieval of information associated with the precise spatiotemporal context in which the information is experienced.”
      • “[E]pisodic memory intimately related to autobiographical memory and the construction of one’s identity in an individual with a history of personal events.”
      • It also helps us to think about future events such as planning tasks and completing to-do lists.
      • Examples: remembering a vacation with family last year, telephone call 1 hour ago, first day of high school, etc.
      • Retrieval: is longer because not only do the facts need to be retrieved but also the context of the memory.
      • Impairment: in the encoding or placement into episodic memory (not correctly encoded), consolidation (high rates of forgetting), retrieval (information is correct if retrieved, but retrieval rate is low)
      • People have difficulty with remembering tasks of activities or planning such activities
      • Impairment causes: head injury, stroke, epilepsy, brain tumor, anoxia/ischemia, carbon monoxide poisoning, ADHD, genetic syndromes such as Down, Kleinfelter, Rett, Velo-cardio-facial or Williams syndrome.
      • Brain areas affected: hippocampus
      • Treatment: treat underlying cause if possible, repetition/practice, memory aids such as mnemonics, stories or other associations
    • Semantic long-term memory
      • Stores facts and general knowledge but does not also store the context.
      • Examples: What is snow? Paraguay is located on what continent? Why is it hot on the equator?
      • Retrieval is fast because context does not also have to be retrieved. The fact is “just known.”
      • It can also be biographical but is not contextual. For example, relatives names, birthdate, nationality, etc.
      • Impairment: poor factual knowledge, difficulty with categorizing (knowing cat and dog are both animals), vocabulary or other language problems
      • Impairment causes: epilepsy, genetic syndromes such as Down syndrome, Fragile X or Williams syndrome
      • Brain areas affected: medial and inferior temporal lobe
    • Procedural long-term memory
      • Procedural memory is a “relatively heterogeneous concept broadly regrouping complex sensorimotor knowledge and skills that are acquired implicitly or explicitly and, once fully automatized, are difficult to verbalize.”
      • Examples: how to ride a bike, skilled reading or speaking, kitchen knife skills, keyboard typing, etc.
      • Impairment: difficulty learning new sensorimotor skills especially language skills
      • Impairment causes: temporal lobe epilepsy, Williams syndrome, or possible dyslexia or specific language impairment
      • Brain areas affected: cerebellum

Questions for Further Discussion
1. What are the recommendations for returning to school or activities after head injury or concussion?
2. How do memory issues affect children in school and what can be done to accommodate the problems?
3. How does sleep relate to memory?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for these topics: Memory and Head Injuries.

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

To view videos related to this topic check YouTube Videos.

Majerus S, Van Der Linden M. Memory disorders in children. Handb Clin Neurol. 2013;111:251-255. doi:10.1016/B978-0-444-52891-9.00027-0

Schneider W, Ornstein PA. Determinants of memory development in childhood and adolescence. Int J Psychol J Int Psychol. 2019;54(3):307-315. doi:10.1002/ijop.12503

Linden M, Hawley C, Blackwood B, Evans J, Anderson V, O’Rourke C. Technological aids for the rehabilitation of memory and executive functioning in children and adolescents with acquired brain injury. Cochrane Database Syst Rev. 2016;7:CD011020. doi:10.1002/14651858.CD011020.pub2

Author
Donna M. D’Alessandro, MD
Professor of Pediatrics, University of Iowa

What Causes Tachycardia?

Patient Presentation
A 25-day-old male came to clinic because he seemed to be eating differently for the past 24 hours. His mother described it as less interested, but he still would breastfeed for 20-30 minutes every 2.5-3 hours, but seemed overall more tired. He had a good suck, didn’t turn blue or sweat during feedings, and maybe was slightly more tired in general. His crying was normal as were his urination and stooling. The mother didn’t think he was having pain, rhinorrhea, cough, or a rash.

The past medical history showed a healthy male born at 40 1/7 weeks gestation without problems. His neonatal screening and critical congenital heart disease tests were negative. He had regained his birth weight by 11 days of age. The family history was negative for any congenital heart disease or arrhythmias. He had a maternal aunt who had an early pregnancy spontaneous abortion. There were no abnormal deaths in the families. The review of systems was otherwise negative.

The pertinent physical exam showed a heart rate of 180-190 beats/minutes, respiratory rate of 36, temperature of 98.9°F, and eventually four-point blood pressures that were normal. His weight was 4.23 kg (50%) and length of 54 cm (50%). HEENT showed a normal fontanele and wet mucous membranes. His heart examination had a III/VI systolic murmur best at the mid-to-lower sternal border that could be heard on the back and axilla but it was difficult to discern because of the sustained tachycardia. Neck and head examinations for murmur radiation couldn’t be appropriately evaluated. Pulses in the upper extremities and lower extremities were normal. His capillary refill was brisk without obvious color changes. His lungs and abdomen were normal. There were no obvious congenital abnormalities on the rest of his examination.

The diagnosis of sustained tachycardia in the setting of a new heart murmur was made. The tachycardia varied between 170-190 beats/minute but mainly stayed in the 180’s range. It did vary with movement or crying of the neonate. The clinic evaluation included an electrocardiogram which showed sinus tachycardia and a chest radiograph which showed a normal heart size.

The patient’s clinical course revealed the patient was transferred to the emergency department for further evaluation where laboratory testing was negative, and the patient’s heart rate had decreased to the 150’s range. Pediatric cardiology was consulted and felt the patient could safely be seen the following day, where an echocardiogram showed a small muscular ventricular septal defect. A Holter monitor was placed with followup planned in 3 days.

Discussion
Tachycardia is a rapid heart rate that is above normal for age and level of exertion. Tachycardia is common, particularly sinus tachycardia due to normally encountered circumstances such as pain, fever or exercise. It is usually a normal physiologic process but sustained tachycardia often indicates a potentially abnormal underlying cause.

Sinus tachycardia has a rapid heart rate with normal P waves and P-R intervals and variations from moment to moment and respiration. Generally it is not over 200 beats/minute. Vagal stimulation can slow the heart rate; this is a gradual slowing, not an abrupt slowing seen in supraventricular tachycardia.

A supraventricular tachycardia has rapid fixed rates, and normal QRS complexes with no discernable P waves or P waves on top of T waves. Vagal stimulation causes no change or an abrupt change to sinus rhythm. Rates are usually 180-300 beats/minute.

Wide QRS complexes with usually a fixed rapid rate is a ventricular tachycardia but can also be a supraventricular tachycardia with ventricular aberration.

History always provides the primary context for evaluating tachycardia including recent illness, feeding problems, exercise or syncope, emotional state and especially medication use.

Physical examination should include evaluation of all vital signs with comparison to normal for age. Fever is commonly noted as can be dehydration when compared to previous weights. Four point blood pressures should be done if possible (congenital heart disease). Cardiac evaluation looking for distant heart sounds and/or pulseus paradoxus (pericardial effusion), S3 or S4 (cardiac dysfunction), and murmur (may be normal for state or are indicate underlying heart disease) can be helpful. Other physical examination findings may be helpful such as dry mucous membranes or prolonged capillary refill (dehydration), tachypnea and hepatomegaly (cardiac failure), poor perfusion (shock), pallor (anemia) and thyromegaly (hyperthyroidism).

Evaluation depends on history and physical examination but especially if a cardiac cause is suspected an electrocardiogram, chest radiograph and general laboratory testing (complete blood count, electrolytes, glucose, and calcium) usually are included in the initial testing. More extensive testing may be needed including echocardiogram, Holter monitoring, etc.

Treatment also depends on the underlying cause. It maybe as simple as calming an agitated patient, or treating a fever. But it can also be much more complicated with necessary specialty care, particularly cardiology.

Learning Point
The differential diagnosis of tachycardia includes:

  • Commonly encountered conditions
    • Anxiety
    • Crying
    • Dehydration
    • Exercise/exertion
    • Fever and/or infection
    • Medications – cough and cold medications, caffeine, legal or illegal drugs
    • Pain
  • Cardiac problems
    • Arrhythmias
      • Supraventricular tachycardia
      • Paroxysmal atrial tachycardia
      • Wolff-Parkinson White syndrome
      • Atrial fibrillation
      • Atrial flutter
      • Junctional tachycardia
      • Ventricular tachycardia
      • Ventricular fibrillation
    • Cardiac state, low or high output
      • Cardiac failure
      • Cardiomyopathy
      • Myocarditis
      • Hypertrophic cardiomyopathy
    • Pleural effusion
  • Other causes
    • Anaphylaxis
    • Anemia, acute or chronic
    • Acute rheumatic fever
    • Cancer
      • Cardiac tumors
      • Catecholine producing tumors
    • Drugs or toxins
      • Alpha-adrenergic agonists
      • Antiarrhythmics
      • Anticholinergics
      • Antidepressants
      • Antihistamines
      • Antimicrobials
      • Antipsychotics
      • Beta-blockers
      • Calcium channel blockers
      • Cardiac glycosides
      • Cholinergics
      • Opioids
      • Organophosphates
      • Sedative-hypnotics
      • Sympathomimetics
      • Arsenic
      • Citrate
      • Fluoride
      • Magnesium
      • Potassium
      • Thallium
      • Thyroid hormone
      • Carbon monoxide
      • Drug withdrawal
      • Caffeine
      • Tobacco
      • Herbals
    • Electrolyte disturbances
      • Hypoglycemia
      • Hypokalemia
      • Hypocalcemia
      • Hypomagnesemia
    • Hypoxemia
    • Hyperthyroidism
    • Kawasaki disease
    • Psychogenic, anxiety or other mental illness

Questions for Further Discussion
1. What are indications for an echocardiogram or Holter monitor?
2. What are indications for invasive treatment such as radioablation for an arrhythmia?
3. How is supraventricular tachycardia treated?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for these topics: Arrhythmias and Congenital Heart Defects

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

To view videos related to this topic check YouTube Videos.

Crosson JE, Callans DJ, Bradley DJ, et.al. PACES/HRS expert consensus statement on the evaluation and management of ventricular arrhythmias in the child with a structurally normal heart. Heart Rhythm. 2014 Sep;11(9):e55-78. doi: 10.1016/j.hrthm.2014.05.010.

Srinivasan C. Diagnosis and Acute Management of Tachyarrhythmias in Children. Indian J Pediatr. 2015;82(12):1157-1163. doi:10.1007/s12098-015-1881-5

Corwin DJ, Scarfone RJ. Supraventricular Tachycardia Associated With Severe Anemia: Pediatr Emerg Care. 2018;34(4):e75-e78. doi:10.1097/PEC.0000000000001134

Mazor S, Mazor R. Approach to the Child with Tachycardia. UpToDate. (rev. 3/2/2019, accessed 12/17/19).

Author
Donna M. D’Alessandro, MD
Professor of Pediatrics, University of Iowa

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What Are Some Risk Factors for Cerebral Palsy?

Patient Presentation
A 5-year-old male came to clinic with increased spasticity for 2 days. He had underlying cerebral palsy and was wheelchair bound and non-verbal. His mother stated that he had not been crying or tearing but had increased spasticity and couldn’t seem to get comfortable. He had some rhinorrhea, but no cough, fever or rash. He had normal urination and had not had any hard stools using her normal bowel regimen. His mother said that when she bathed him she didn’t see any skin lesions or break down. His seizure pattern was also unchanged.

The past medical history showed he was a former 32-week premature infant who had a complicated neonatal intensive care stay. He was followed by multiple specialties including neurology, developmental disabilities, gastroenterology, and orthopaedics and he received comprehensive therapy services at school and in the community. The review of systems was not contributory.

The pertinent physical exam showed him posturing more than normal during the visit but there were times when he relaxed. His vital signs were normal, but a new weight was not obtained. His oxygen saturation was 97% on room air. HEENT showed clear rhinorrhea and a reddened pharynx without exudate but with palatal and peritonsilar vesicles. His ears were normal. Lungs, heart and abdomen were normal. His palms and soles had several 2-3 mm vesicles. There were no other lesions noted. His neurological examination showed increased spasticity in all extremities, but again he could relax at times. He was non-verbal but possibly reacted more during his HEENT examination.

The diagnosis of hand, foot and mouth disease was made. “It looks like he is having hand, foot and mouth infection. For some kids they don’t have many symptoms and for others they can have a lot. Maybe his mouth is bothering him more than we realize or he just plain doesn’t feel good. Why don’t we try to give him some ibuprofen on a schedule and see what happens. He doesn’t seem to be a lot more affected like he’s not having more seizures or doesn’t seem to have a second infection like an ear infection,” the pediatrician discussed. “Okay. He’s had an orthopaedic appointment to watch his hips and a wheel-chair fitting appointment in 2 days, so I could come back then if he’s not getting better,” the mother replied.

Discussion
The term, cerebral palsy, or CP has gone through many iterations with the first description in 1861 by W.J. Little who described it as “The condition of spastic rigidity of the limbs of newborn children.” The most recent definition is from Rosenbaun et al. in 2007 which states it is “a group of permanent disorders of the development of movement and posture, causing activity limitation, that are attributed to non-progressive disturbances that occurred in the developing fetal or infant brain. The motor disorders of cerebral palsy are often accompanied by disturbances of sensation, perception, cognition, communication, and behaviour, by epilepsy, and by secondary musculoskeletal problems.”

The incidence is about 2-3/1000 live births in high income countries but higher in low income countries. CP can be a severe motor problem for children and adults with up to 40% of patients unable to walk independently.

CP is really a clinical diagnosis with help from neuroimaging. It basically includes using history, some standardized physical examination ratings (i.e. Prechtl General Movement Assessment and Hammersmith Infant Neurological Examination), and cranial ultrasound or MRI which may show findings consistent with the history and physical examination such as intraventricular hemorrhage, cerebral or cerebellar hemorrhage, posthemorrhagic ventricular dilatation, or cystic periventricular leukomalacia. Diagnosis can be made within the first 6 months but this is usually in infants who have more problems. Patients are usually diagnosed after a year when the clinical trajectory of the patient and their individual problems are more consistent. This does not mean that a patient and family should wait for a diagnosis of CP to receive developmental surveillance and treatment if there are risk factors or concerns about the patient.

Any motoric area can be affected and subtypes are named for the area affected and how it is affected. For example, with predominantly the lower limbs (diplegia), the arm and leg on one side (hemiplegia) or all of the body (quadriplegia), and/or spasticity, dystonia (the two most common movement disorders with CP) and or dyskinesia.

The patient’s abnormal movements vary by the patient and the age. Patients with CP have a wide variety of comorbid problems, with the percentages given from high-income countries.

  • Chronic pain – 75%
  • Intellectual disability – 49%
  • Unable to walk independently – 40%
  • Epilepsy – 35%
  • Hip subluxation – 28%
  • Bladder control problems – 24%
  • Non-verbal – 23%
  • Sleep problems, pathological – 23%
  • Sialorrhea – 22%
  • Blind, functionally – 11%
  • Feeding tube requirement – 6%
  • Hearing impairment, severe 4%

Treatment includes managing the overall patient’s health, preventive services, specific services for their problems and early intervention services. Early intervention services are multidisciplinary services that focus on assisting the patient in all developmental areas including potentially physical therapy, occupational therapy, speech therapy, social interactions and cognitive interactions. Data more strongly supports benefits in cognition but less so for motor development. Other needs may include:

  • Spasticity and dystonia – physical therapy, occupational therapy, splinting, medications (i.e. Baclofen, Botulinum toxin A, Clonidine, Diazepam, Gabapentin), or neurosurgical interventions (i.e. selective dorsal rhizotomy, deep brain stimulation)
  • Hip dysplacement is common and needs ongoing screening particularly if the child is less mobile or immobile
  • Feeding and nutrition – difficulty swallowing, aspiration and drooling can be major problems for patients
  • Pain – this is common because of constipation, hip dislocation, spasticity and dystonia
  • Sleep disturbance – often because of other problems listed above, and may require behavioral interventions and medication

Learning Point
CP’s cause is not entirely known but appears to be multifactorial especially with accumulations of potential insults. Gestational age is a strong factor. Unfortunately for many of the risk factors, there are no easy or obvious treatments or preventive practices for them.

Rick factors for CP include:

  • Pregnancy
    • Genetics – higher risk in siblings particularly twins
    • Fetal growth restriction
    • Infections
    • Maternal obesity
    • Multiple births
    • Preeclapsia
    • Prolonged labor
    • Socioeconomic status, lower
  • Perinatal
    • Prematurity – 14.6% in gestation age 22-27 weeks, 6.2% in 28-31 weeks, 0.7% in 32-36 weeks, 0.11% in term infants
    • Post-maturity
    • Low birth weight
    • Small for gestational age
    • Birth defects
    • Birth complications – fetal bradycardia, low Apgar score, delayed time to first breath, breech position are some risk factors
    • Chorioamnionitis
    • Infection/inflammation
    • Kernicterus
    • Seizures
    • Stroke, perinatal
    • Abnormal neuroimaging findings
    • Post natal corticosteroid use
    • Early surgery
    • Mechanical ventilation
  • Protective factors for CP include:
    • Magnesium sulfate treatment for mother during pregnancy
    • Caffeine therapy for the infant
    • Brain or body cooling for the infant

    Questions for Further Discussion
    1. What are indications for referral to a developmental disabilities specialist?
    2. What does non-verbal mean? A review can be found here
    3. What is the classification for intraventricular hemorrhage? A review can be found here

    Related Cases

    To Learn More
    To view pediatric review articles on this topic from the past year check PubMed.

    Evidence-based medicine information on this topic can be found at SearchingPediatrics.com and the Cochrane Database of Systematic Reviews.

    Information prescriptions for patients can be found at MedlinePlus for this topic: Cerebral Palsy

    To view current news articles on this topic check Google News.

    To view images related to this topic check Google Images.

    To view videos related to this topic check YouTube Videos.

    Little W.J. Transaction of the Obstretrical Society of London. Longmans, Green and Co. 1862: 293-344.

    Spittle AJ, Morgan C, Olsen JE, Novak I, Cheong JLY. Early Diagnosis and Treatment of Cerebral Palsy in Children with a History of Preterm Birth. Clin Perinatol. 2018;45(3):409-420. doi:10.1016/j.clp.2018.05.011

    Graham D, Paget SP, Wimalasundera N. Current thinking in the health care management of children with cerebral palsy. Med J Aust. 2019;210(3):129-135. doi:10.5694/mja2.12106

    Korzeniewski SJ, Slaughter J, Lenski M, Haak P, Paneth N. The complex aetiology of cerebral palsy. Nat Rev Neurol. 2018;14(9):528-543. doi:10.1038/s41582-018-0043-6

    Lins LAB, Watkins CJ, Shore BJ. Natural History of Spastic Hip Disease. J Pediatr Orthop. 2019;39(Issue 6, Supplement 1 Suppl 1):S33-S37. doi:10.1097/BPO.0000000000001347

    Author
    Donna M. D’Alessandro, MD
    Professor of Pediatrics, University of Iowa