The Ethical Debate About the Neuropsychological Assessment of Young People With Visual Impairments

Neuropsychology is the study of the relationship between brain function and cognition, behavior, and emotion. Neuropsychological assessments with young people aim to understand cognitive strengths and deficits and generate individualized recommendations to guide interventions. Neuropsychological assessment differs from educational assessment and simple intelligence testing in that it seeks to understand the effect of neurological events on thinking, communication, behavior, and social functioning. Neuropsychological testing often extends beyond the use of standard intelligence tests to include measures of verbal and visual memory, attention, and executive function. Young people are referred for neuropsychological assessments following identified or suspected disruption to the integrity of the brain or when there are concerns about atypical neurodevelopmental progress. Education is a key aspect of development in youth; concerns often arise when learning progress is judged to be slower than expected for a child's age. A child may present for neuropsychological assessment with visual impairment (i.e., blindness or low vision) caused by the same mechanism that resulted in potential cognitive impairment. Cortical visual impairment (also referred to as cerebral visual impairment, CVI) occurs when visual pathways are compromised in a child's brain. For example, it can occur in the case of hypoxic ischemic encephalopathy following preterm birth but can also occur because of seizures, hydrocephalus, traumatic injury, brain tumors, infection, or genetic conditions. Comorbid neurological conditions that affect cognition are common in children with CVI (Huo et al., 1999; Khetpal & Donahue, 2007) with authors suggesting that 10% of children with developmental disabilities have CVI (Nielsen et al., 2007). Children may also present with low vision or complete blindness, due to congenital visual impairments and genetic conditions affecting the structures of the eye, which would not necessarily be expected to have also influenced cognition. Neuropsychological assessment of young people who have visual impairments is complex and challenging for the clinical neuropsychologist. A clinician needs to err away from falsely attributing poor test performance to a cognitive deficit if a child's visual impairment has affected the assessment. However, there is also an ethical responsibility to detect cognitive impairment if it is present and ensure appropriate intervention for children with visual impairments. A debate exists about whether it is ethical to conduct neuropsychological testing with children who have visual impairments. The aim of this report is, first, to highlight the salient points from each side of the debate, and, second, to suggest a practical way forward for clinicians presented with a young person who has a visual impairment.

Ethical Limitations in the Assessment of Young People With Visual Impairments

The aptitude tests used by neuropsychologists to quantify function in cognitive domains compare a child's performance against a normative group to determine whether they fall outside the average range for their age and sex. Using neurocognitive test norms with people who have visual impairments may be biased and, therefore, violate an underlying tenet of assessment (Lund et al., 2014). Normative samples are predicated upon strict, standardized administration protocols to minimize inter-rater bias, but their utility for the assessment of children with visual impairments is limited (Minks et al., 2020; Nicholas, 2020). Adaptations to test administration, including magnification of materials and additional time allowance, deviates from the standardized protocol rendering the results not strictly comparable to the normative group. Furthermore, normative samples do not include children with visual impairments. Comparing the performance of a child with visual impairment to that expected of a child with typical vision can lead to the misattribution of poor performance to a cognitive deficit rather than the visual impairment (Dial & Dial, 2009).

Although it is tempting to solve this problem by creating a normative sample of youths with visual impairments to provide an appropriate reference group, this strategy is not straightforward. Visually impaired young people are a heterogeneous group. The etiology of vision loss, timing and nature of onset, recency of impairment, and the presence of other disabilities all influence how well a child might perform on cognitive tests, thereby making comparisons to other children with visual impairments problematic (Dial & Dial, 2009; Loftin, 1997).

Cognitive tests are useful because they correlate with functional capability. They tell the clinician something about whether a child's cognitive skills are following the expected developmental trajectory for their age. However, this correlation is more tenuous in children with visual impairments. Depending on the nature and onset of vision loss, the developmental trajectory is heterogenous among children with visual impairments. A child who has acquired a visual impairment may have developed different adaptive strategies than a child born with congenital blindness. Dale and Salt (2008) observed what they termed a setback in development of children aged 16–27 months who were blind or severely visually impaired and whose vision loss was the result of damage to the eye, retina, or anterior optic nerve, rather than the result of a neurological condition that might have also affected cognition (Dale & Salt, 2008). However, it is not clear whether the identified developmental setback represents a slowing of developmental progression or a developmental pathway that is different in children who have a visual impairment, but not indicative of a cognitive deficit (Vervloed et al., 2020). If the utility of neurocognitive tests for predicting the functional outcome is weak in the case of children with visual impairments, their usefulness in assessing these children is questionable (Minks et al., 2020). This possibility reinforces the need for clinicians to be conscious of the complexity involved in assessing the cognitive, behavioral, and social development of children with visual impairments.

The Right to Access Neuropsychological Assessment

While evaluating a child with a visual impairment is complex and has important ethical considerations, the clinical neuropsychologist has a responsibility to ensure children with disabilities are not disadvantaged in access to high-quality assessment and intervention (Hill-Briggs et al., 2007).

Neuropsychological assessments are more than the reporting of neurocognitive test results. They synthesize into formulation information from developmental history, medical background, social and demographic information, observer reports of the child in educational and home settings, clinician knowledge of brain-behavior relationships, and understanding of typical child development (Donders, 1999). If psychometric test results (e.g., intelligence quotient tests, measures of attention and memory) are one source of information used carefully within the broader formulation of a neuropsychological assessment, they can aid in understanding the cognitive and adaptive functioning of children with visual impairments. Thus, the tenets of neuropsychological assessment as a wholistic formulation of the child are consistent with the recommendations outlined in the position paper on the assessment of young people with visual impairments (Goodman et al., 2011).

Neurocognitive testing can provide information about a child's ability to use adaptive strategies such as auditory working memory (the ability to temporarily hold and use verbal information mentally) and learning to compensate for the effect of their visual impairment (Warren, 1994). This information aids the clinician in making useful recommendations that are suitable for an individual child's needs.

Recommendations for Clinicians

Amid this debate, individual practitioners continue to receive referrals for neuropsychological assessment of children who have visual impairments. If the focus remains on the purpose of the assessment: to identify current deficits and function with a view to recommendations, then there is a pathway for practitioners to proceed ethically.

When preparing to assess a child with a visual impairment, the neuropsychologist should understand the nature of a child's vision loss. It must extend beyond understanding visual acuity and visual field quantification to include an understanding of the functional effect of the impairment in the home and at school from parents and educators (Chang & Borchert, 2021; Goodman et al., 2011; Loftin, 1997). Timing of onset, rate of progression, and recency of impairment will also influence how a young person has adapted to vision loss (Minks et al., 2020).

Pediatric neuropsychologists use a hypothesis-testing approach when selecting tests; this approach is essential when assessing children with visual impairments. Verbal measures may provide helpful information about a child's capacity to use verbal strategies to compensate for impairments in visual problem-solving or visual processing speed. However, performance on verbal measures cannot be extrapolated to reflect intellectual ability overall (Minks et al., 2020). As with all such assessments, clinicians need to be clear about the underlying cognitive construct the test is assessing and be able to justify the use of subtests (Hannan, 2007).

A clinician can adapt subtests with visually presented stimuli using magnification, prism lenses, or telescopic lenses. Adaptations generally violate standard test administration rules, rendering normative data for these tests invalid. Some argue that if an explanation of significant caveats about the use of tests is required, they should not be used in the first place (Minks et al., 2020). In their position paper on assessment of people with visual impairment, Goodman et al. (2011) highlight the need to present a clear rationale for assessment and clinical judgements drawn from test results. Thus, the issue of test selection is closely related to one of test interpretation.

Perhaps the most difficult aspect of formal testing of children with visual impairments occurs in the interpretation of tasks reliant on visual material. In this situation, a clinician needs more information, particularly from teachers who are likely to have observed a child engaging in visual tasks at school (Loftin, 1997). Multi-informant reports of function contribute much to assessment of children with visual impairments (Nicholas, 2020). Including other forms of hypothesis testing of in-home or school-based functional skills provides additional collateral information to assist in interpreting test results (Sechrest, 2005). Liaison with teachers of students with visual impairments is a critical component of assessment in children with visual impairments (Loftin, 1997). Because they work closely with the young person in an educational context, these teachers have a depth of understanding about the functional impact of vision loss. This information can aid the clinician in identifying how test materials can be adapted, improving accuracy of clinical judgments, and ensuring recommendations are appropriate for the individual.

Evidence from research and experience from clinical practice suggest that clinicians can provide a valued and specialized service to children and adolescents with visual impairments if they:

ensure a good understanding of the cause, nature, and timing of a child's visual impairment that extends beyond simple visual acuity or visual field metrics (see Goodman et al., 2011 for information about common eye conditions);

include information from functional vision assessments and feedback from educators who work with the child when planning, conducting, and interpreting the assessment;

possess a comprehensive understanding of the underlying cognitive constructs being assessed;

are aware of the limitations of normative samples as a reference group for children with visual impairments;

use a hypothesis-testing approach to test selection;

use multiple sources of information to formulate an opinion on a child's cognitive abilities (in particular, educators can provide specific insights into the child's adaptive strategies); and

focus on individualized recommendations informed by a deep understanding of the child's strengths and difficulties.

In conclusion, neuropsychologists provide a comprehensive assessment of cognitive, behavioral, and social functioning in children. Synthesizing information from multiple sources and bringing it together into a comprehensive report assists health professionals, teachers, and parents to support a young person who has cognitive difficulties and a visual impairment. A neuropsychologist does more than simply collate information; they provide an informed clinical formulation of the child's difficulties. The neuropsychologist then translates the formulation into individualized recommendations for cognitive rehabilitation. If the neuropsychologist conducts a careful, hypothesis-driven assessment focused on understanding what the child has difficulty with, then identifying helpful interventions can support young people with visual impairments.