Neuropsychological Assessment in the Forensic Context: A Scoping Review

. The introduction of neuropsychologists in legal practice allowed for the field of forensic neuropsychology to arise. However, it is still a recent field of knowledge that is in continuous development. The existing literature highlights the incipience of studies in this area and the need for adaptation of instruments and methods. Thus, this scoping review aims to analyze how neuropsychological assessment has been employed so far in the forensic context. In order to do this, a search and a follow-up were conducted in the databases PsycInfo, Scopus and Web of Science. The query used for both searches was "(neuropsychological assessment OR neuropsychological test)" AND "forensic" OR "forensic neuropsychology". Initially, 1001 papers were identified, and after a two-stage screening process, 83 articles were included for analysis. Regarding neuropsychological assessment, the most investigated constructs were cognitive levels, memory and symptom validity. The heterogeneity of employed instruments we found in the studies evidenced the great existing variability in forensic neuropsychological practice. Among the most assessed populations were individuals with psychiatric, psychological or neurological diagnoses and male adult detainees in general. With this review, we expect to provide an overview on the current state of forensic neuropsychology, as well as information that may serve as a starting point for new research and further developments in the field.


Introdução
The justice system requires scientifically based evidence in order to make the fairest and most appropriate decisions possible. Thus, it is always looking for other fields of knowledge and new methods to support its decision-making process 1 . One such field is neuropsychology, and the intersection between its methods and the law has recently established itself as a new field of study and practice.
The development of systematic methods for evaluating psychological consequences from traumatic events and investigating the association of affective and cognitive processes in socially disruptive behavior has allowed neuropsychology to find space to enter the boundaries of legal practice 2 . Due to it being an evidence-based way of addressing the relationship between brain (mental state) and behavior, neuropsychology can significantly contribute to understanding criminal conduct or civil demands 3 in forensic contexts.
Neuropsychological assessment results can also provide important complementary data to other professionals in situations related to the law 1 .
The introduction of neuropsychologists in legal practice has thus generated the field called forensic neuropsychology. It is still a recent field of knowledge, in continuous development, and the existing literature highlights the incipience of studies in the area regarding the necessity of ethical adaptation of instruments and methods to the legal context 4 .
Ensuring that the instruments and methods of forensic neuropsychology are adapted to ethical principles is vital. Otherwise, there is a risk of nonscientific and questionable practices occupying this field of intervention 3 . This evidences the importance of developing ethical guidance alongside the field itself 5 , as well as the need to educate and train forensic neuropsychologists, given the insufficiency of specialized professionals to meet current demands 6 .
The inappropriate use of neuropsychological knowledge can contribute to spreading prejudices, stigmatizing notions and over-pathologizing of issues related to mental disorders and their possible correlation with judicial problems 2 .
Responsible application of this knowledge ensures a reliable and evidencebased practice, granting forensic neuropsychology the potential to assist in the primary function of the judiciary system: the search for truth and the promotion L. V. da Silva & A. C. Hamdan of justice 3 . However, in order to do so, a clearer notion of how forensic neuropsychological practice stands in its current form is required.
Hence, the main objective of this scoping review is to analyze how neuropsychological assessment has been used in the forensic context. Specifically, we intend to answer three questions: (1) What is the purpose of neuropsychological assessments in the legal context? (2) What are the most used instruments in neuropsychological assessments? (3) In the forensic context, neuropsychological assessment is commonly used to assess which population? Thus, we expect to provide an initial and broad screening of forensic neuropsychology, adding to the existing reflections on issues present in the literature.

Protocol
The present study consists of a scoping review of the literature on forensic neuropsychology, aiming to understand how neuropsychological assessment has been used in the forensic context. Scoping reviews are a technique used to systematically map broader concepts and topics in a research area 7 allowing researchers to identify the main terms, theories, sources of evidence and gaps in the analyzed field 8 .

Data sources and search strategy
The initial search was conducted in the electronic databases PsycInfo, Scopus and Web of Science, on August 19th, 2020. The search query used was "(neuropsychological assessment OR neuropsychological test)" AND "forensic" OR "forensic ne uropsychology". A follow-up search was conducted on June 12th, 2022, to identify any additional articles published after the initial search.
This was done in order to update our findings and to further base this review.
The same three databases were consulted, and the search query was identical to the one used in the first search.

Eligibility criteria
Studies were eligible for inclusion if they had (a) empirical research designs (not systematic or literature reviews, descriptive studies, letters to the editor, book

Study selection process
A two-stage screening process was used to assess the relevance of studies

Data extraction process and final sample
The following data were extracted from the 142 studies selected from the first search: the complete reference, type of study design, sample characteristics and instruments utilized. After this in-depth reading of the 142 articles, the papers inconsistent with the purpose of the review (n = 77) were excluded, totalizing 65 studies selected for complete analysis.
The same data was extracted from the 31 articles included in the follow-up search. After this in-depth reading, other 13 papers were excluded for not being consistent with the purpose of this review, totalizing 18 studies selected for the complete analysis. Adding the two searches together, a total of 83 papers were analyzed in this review.

Results
The literature search resulted in a total of 1001 articles (sum of the records identified in the initial and follow-up search; see Figure 1 and Figure 2). After the exclusion of the duplicate papers (n = 236) and the analysis of titles and abstracts, 592 articles were excluded, and the data of 173 were extracted. 90 other studies were then excluded for being inconsistent with the review's purpose. The final 83 articles were included for analysis.
In total, 41 articles (49%) used at least one neuropsychological test to investigate the sample's intelligence levels. Neuropsychological instruments were used by 24 papers (29%) to evaluate memory. Symptom validity was Overall, more than 140 different types of instruments were identified. Table 1  Furthermore, another 8 (10%) papers focused on investigating patients with a history and diagnosis of neurological conditions, such as stroke, acquired brain injury, traumatic brain injury or dementia. 45 (54%) papers focused on the forensic population involved in criminal or civil lawsuits without identified or diagnosed health conditions. 18 (22%) were adults arrested for one or more crimes (in general). 13 (16%) investigated individuals convicted of violence or assault -3 (4%) specifically for sexual assault and 4 (5%) for sexual abuse or assault against minors. 7 (8%) articles assessed adolescents or children who committed a crime or were incarcerated. 5 (6%) investigated adults who committed murder, but only one paper focused specifically on women convicted of this crime. 2 (2%) recent papers also focused on evaluating veterans and U.S. service members' justice claims.
Finally, 2 others (2%) assessed children who were victims of crime.

What is the purpose of neuropsychological assessments in the legal context?
From the analysis of the 83 selected articles, we ascertained that 47% of the studies involving the application of tests sought to investigate the validity of the symptoms presented by those evaluated [9][10][11][12][13] . This data is congruent with legislation that determines that deficits or neurological conditions can decrease sentence time, legally acquit the accused or even provide monetary compensation in civil cases 14  An expressive number of articles stated that neuropsychological assessment is commonly conducted to investigate the individual's cognitive functions. Intelligence tests were used in 49% of the studies, which may be related to the fact that cognitive deficits have an influence on volitional behavior and, consequently, with criminality [19][20][21] . Also, cognitive impairment and competence to stand trial could be associated factors 18 , which demands more research to further explore this correlation. Intelligence levels in forensic contexts are also an up-to-date relevant research topic, since it was found that the estimated prevalence of intellectual disability in the forensic population appears to be higher than expected 22 .
Memory functions are also commonly investigated since they have significant associations with the validity of individuals' performance or symptoms 14,[23][24][25] . As well as witness capability to provide evidence in a trial 26 .
The importance of global neuropsychological assessment in the forensic context can also help in the examination of specific situations such as, for example, simulation of symptoms and performance in tests [27][28][29] .

What are the most used instruments in neuropsychological assessments?
Neuropsychological assessment is mostly used to assess cognitive and memory functions and the presence of neuropsychiatric symptoms. In this review, a significant variability of assessment instruments was observed (140 different types of tests). Therefore, there is a lack of standardization regarding the tools for neuropsychological assessments in the forensic context and an indication that a wide variety of neuropsychological functions are being evaluated in different ways. This fact can be expected due to the field of neuropsychology being relatively recent. However, the lack of standardization of the instruments used by neuropsychologists is also pointed out as a possible problem, since there is evidence showing it can compromise the reliability of results in neuropsychological assessments, the quality of these procedures and how this information is understood by legal professionals 2 . This data also aligns with the previous discussion regarding the young age of this research field 2 . Since it is still an expanding area for the use of neuropsychological knowledge and practice 3 , it is expected to be at a stage where neuropsychological instruments are being validated for the forensic population and settings and their usage is thus widely variable.
It is important to highlight that restricting detainees' hands (through the use of handcuffs) during the execution of neuropsychological tests can affect the performance of the assessed individuals 51 . Therefore, the generalization of forensic neuropsychological assessments and their results must be considered with caution and properly contextualized.

In the forensic context, neuropsychological assessment is commonly used to assess which population?
Neuropsychological assessment has been employed to assess a wide variety of Regarding the underage population convicted of crimes, the general objective of the studies was to try to identify executive dysfunctions in these individuals [83][84][85][86] . They also investigated possible risk factors for minors to develop criminal behavior in relation to previous environmental conditions, life experiences and comorbid conditions 87,88 .
Other papers focused on the people who were convicted of homicide.
This population was primarily evaluated to identify common neuropsychological deficits and association with criminal behavior 89,90 . Associated disorders and risk factors related to recidivist criminal action were also investigated 91

Limitations
The main limitation of this study concerns the eligibility criteria. In this review, only empirical articles were included, which may limit the scope of the obtained information. Future research could include theses, dissertations, book chapters, and literature reviews in order to provide additional information on neuropsychological assessment in the forensic context.

Conclusion
This review aimed to analyze how neuropsychological assessment has been used in the forensic context. The results showed the main purposes of the assessment, instruments used, and types of populations investigated. Neuropsychologists are gaining more space in the forensic sphere to intervene in many different demands. However, we found there is a wide variety of instruments used in neuropsychological evaluation, and this has possible negative repercussions. Standardizing forensic neuropsychological assessment procedures is necessary in order to safely continue the development of this field and guarantee more reliable assessment results.
Finally, we aimed to provide a profile of the current state of forensic neuropsychology and information that may serve as a starting point for new research that covers topics that were sparsely addressed or not addressed at all in the studies analyzed here. Through this research, neuropsychology can continue to expand and improve its space in the forensic context. It can also fulfill, in a reasoned and ethical manner, its objectives and responsibilities of L. V. da Silva & A. C. Hamdan basing judicial decisions, which, in turn, will bring significant consequences for the lives of a great number of individuals.