Warrington Recognition Memory Test Research Articles

Detecting feigned cognitive impairment using pupillometry on the Warrington Recognition Memory Test for Words

ABSTRACT Objective Pupillometry provides information about physiological and psychological processes related to cognitive load, familiarity, and deception, and it is outside of conscious control. This study examined pupillary dilation patterns during a performance validity test (PVT) among adults with true and feigned impairment of traumatic brain injury (TBI). Participants and Methods Participants were 214 adults in three groups: adults with bona fide moderate to severe TBI (TBI; n = 51), healthy comparisons instructed to perform their best (HC; n = 72), and healthy adults instructed and incentivized to simulate cognitive impairment due to TBI (SIM; n = 91). The Recognition Memory Test (RMT) was administered in the context of a comprehensive neuropsychological battery. Three pupillary indices were evaluated. Two pure pupil dilation (PD) indices assessed a simple measure of baseline arousal (PD-Baseline) and a nuanced measure of dynamic engagement (PD-Range). A pupillary-behavioral index was also evaluated. Dilation-response inconsistency (DRI) captured the frequency with which examinees displayed a pupillary familiarity response to the correct answer but selected the unfamiliar stimulus (incorrect answer). Results All three indices differed significantly among the groups, with medium-to-large effect sizes. PD-Baseline appeared sensitive to oculomotor dysfunction due to TBI; adults with TBI displayed significantly lower chronic arousal as compared to the two groups of healthy adults (SIM, HC). Dynamic engagement (PD-Range) yielded a hierarchical structure such that SIM were more dynamically engaged than TBI followed by HC. As predicted, simulators engaged in DRI significantly more frequently than other groups. Moreover, subgroup analyses indicated that DRI differed significantly for simulators who scored in the invalid range on the RMT (n = 45) versus adults with genuine TBI who scored invalidly (n = 15). Conclusions The findings support continued research on the application of pupillometry to performance validity assessment: Overall, the findings highlight the promise of biometric indices in multimethod assessments of performance validity.

89 Detecting Feigned Cognitive Impairment Using Pupillometry on the Warrington Recognition Memory Test for Words

Objective:Traditional methods of assessing performance validity have numerous weaknesses, among them, results can be consciously manipulated by examinees who wish to feign cognitive impairment. This study tested the ability of pupillary dilation patterns during a performance validity test (PVT) to enhance diagnostic accuracy in discriminating true from feigned impairment of traumatic brain injury (TBI). Pupillometry provides information about physiological and psychological processes related to cognitive load, familiarity, and deception and is outside of conscious control. Patrick, Rapport, Kanser, Hanks, and Bashem (2021) established proof of concept for the utility of pupillometry with PVTs applied to the Test of Memory Malingering (TOMM). This study replicated and extended this work by evaluating the incremental utility of pupillary-derived indices on the Warrington Recognition Memory Test for Words (RMT).Participants and Methods:Participants included 214 adults in three groups: adults with bona fide TBI (TBI; n = 51) healthy comparisons instructed to perform their best (HC; n = 72), and healthy adults instructed and incentivized to simulate cognitive impairment due to TBI (SIM; n = 91). Moreover, this study examined pupillary pattern differences among successful (i.e., failed < 1 PVT and performed impaired on cognitive tests) and unsuccessful (i.e., failed > 2 PVTs or did not score impaired on a cognitive test) SIM, including SIM who did and did not fail the RMT. The RMT was administered in the context of a comprehensive neuropsychological battery. Indices included two pure pupil dilation (PD) indices: a simple measure of baseline arousal (PD-Baseline) and a nuanced measure of dynamic engagement (PD-Range). A pupillo-behavioral index was also evaluated: Dilation-response inconsistency (DRI) captured the frequency with which examinees displayed a pupillary familiarity response to the correct answer but selected the unfamiliar stimulus (incorrect answer).Results:The results generally replicated Patrick et al. (2021), as all three indices were useful in discriminating between groups and provided incremental utility to traditional accuracy scores. PD-Baseline appeared sensitive to oculomotor dysfunction due to TBI (i.e., increasing accurate identification of that group); adults with TBI displayed significantly lower chronic arousal as compared to the two groups of healthy adults (SIM, HC). In fact, the TBI group showed significantly lower PD-Baseline than both unsuccessful simulators who were detected as feigners and successful simulators who passed PVTs but effectively feigned TBI on other tests. Dynamic engagement (PD-Range) yielded a hierarchical structure such that SIM were more dynamically engaged than TBI followed by HC. As predicted, simulators engaged in DRI significantly more frequently than other groups. Moreover, DRI added unique information to RMT accuracy in classifying unsuccessful simulators from all other groups. Each of these three pupillary indices showed large effect sizes, and logistic regressions indicated that each contributed unique variance in predicting group membership on one or more of the paired contrasts (i.e., SIM-TBI, SIM-HC, HC-TBI).Conclusions:Taken together, the findings support continued research on the application of pupillometry to performance validity assessment: Pupillometry provided unique information in enhancing classification accuracy beyond traditional PVT accuracy scores. Overall, the findings highlight the promise of biometric indices in multimethod assessments of performance validity.

Specificity of performance validity tests in patients with confirmed epilepsy

Objective: While assessment of performance validity is essential to neuropsychological evaluations, use of performance validity tests (PVTs) in an epilepsy population has raised concerns due to factors that may result in performance fluctuations. The current study assessed whether specificity was maintained at previously suggested cutoffs in a confirmed epilepsy population on the Warrington Recognition Memory Test (WRMT) – Words and Test of Memory Malingering (TOMM). Method: Eighty-two confirmed epilepsy patients were administered the WRMT-Words and TOMM as part of a standardized neuropsychological evaluation. Frequency tables were utilized to investigate specificity rates on these two PVTs. Results: The suggested WRMT-Words Accuracy Score cutoff of ≤42 was associated with a specificity rate of 90.2%. Five out of the 8 individuals falling below the Accuracy Score cutoff scored 42, suggesting specificity could be further improved by slightly lowering the cutoff. The WRMT-Words Total Time cutoff of ≥207 seconds was associated with 95.1% specificity. A TOMM Trial 1 cutoff of <40 was associated with 93.9% specificity, while the established cutoff of <45 on Trial 2 and the Retention Trial yielded specificity rates of 98.6% and 100.0%, respectively. Conclusions: Our findings demonstrate acceptable performance on two PVTs in a select confirmed epilepsy population without a history of brain surgery, active seizures during testing, and/or low IQ, irrespective of various factors such as seizure type, seizure lateralization/localization, and language lateralization. The possible presence of interictal discharges were not controlled for in the current study, which may have contributed to reduced PVT performances.

Are there differences in performance validity test scores between African American and White American neuropsychology clinic patients?

ABSTRACT Objective The purpose of the present study was to compare performance on a wide range of PVTs in a neuropsychology clinic sample of African Americans and White Americans to determine if there are differences in mean scores or cut-off failure rates between the two groups, and to identify factors that may account for false positive PVT results in African American patients. Method African American and White American non-compensation-seeking neuropsychology clinic patients were compared on a wide range of standalone and embedded PVTs: Dot Counting Test, b Test, Warrington Recognition Memory Test, Rey 15-item plus recognition, Rey Word Recognition Test, Digit Span (ACSS, RDS, 3-digit time, 4-digit time), WAIS-III Picture Completion (Most discrepant index), WAIS-III Digit Symbol/Coding (recognition equation), Rey Auditory Verbal Learning Test, Rey Complex figure, WMS-III Logical Memory, Comalli Stroop Test, Trails A, and Wisconsin Card Sorting Test. Results When groups were equated for age and education, African Americans obtained mean performances significantly worse than White Americans on only four of 25 PVT scores across the 14 different measures (Stroop Word Reading and Color Naming, Trails A, Digit Span 3-digit time); however, FSIQ was also significantly higher in White American patients. When subjects with borderline IQ (FSIQ = 70 to 79) were excluded (resulting in 74 White Americans and 25 African Americans), groups no longer differed in IQ and only continued to differ on a single PVT cutoff (Trails A). Further, specificity rates in African Americans were comparable to those of White Americans with the exception of the b Test, the Dot Counting Test, and Stroop B. Conclusions PVT performance generally does not differ as a function of Black versus White race once the impact of intellectual level is controlled, and most PVT cutoffs appear appropriate for use in African Americans of low average IQ or higher.

A-181 Do Effortful Epilepsy Patients Fall Below Performance Validity Test Cutoffs at Higher Rates than Is Considered Acceptable?

Abstract Objective Factors specific to an epilepsy population (e.g., medications, psychiatric comorbidities, localization) may result in higher false positive rates on performance validity tests (PVT), rendering the results more equivocal. This study examined whether specificity is reduced in effortful epilepsy patients on the Warrington Recognition Memory Test - Words (WRMT-W) and Test of Memory Malingering (TOMM). Method 53 epilepsy patients referred for neuropsychological evaluation through the University of Washington Regional Epilepsy Center were examined. Patients were majority male (56.6%) and Caucasian (79.2%). Average age and education were 36.1 (SD = 13.03) and 13.4 years (SD = 2.39), respectively. Patients with an intelligence quotient of &amp;lt;70, history of brain surgery, and those who seized during testing were excluded. Patients clinically observed to have reduced effort with 2+ PVT failures were excluded (n = 3). Frequency tables for WRMT-W and TOMM performances were utilized to examine specificity based on prior cutoffs identified for these measures. Results The WRMT-W cutoff of ≤42 was associated with 88.7% specificity. TOMM Trial 2 and Retention cutoffs of &amp;lt;45 were associated with 98.1% and 100% specificity, respectively. The WRMT-W cutoff was associated with 91.7% specificity in language dominant hemisphere onset epilepsy patients (n = 16). None performed below cutoffs on the TOMM. All nondominant hemisphere onset patients (n = 8) performed above WRMT-W and TOMM cutoffs. Conclusions Use of the WRMT-W and TOMM in an epilepsy population is associated with an acceptable false positive rate (specificity around 90%). However, future studies examining the sensitivity of these measures in epilepsy patients should be performed.

Facial memory ability and self-awareness in patients with temporal lobe epilepsy after anterior temporal lobectomy.

Anterior temporal lobectomy (ATL) is the most common surgical treatment for drug-resistant temporal lobe epilepsy (TLE). Right ATL has been reported to reduce facial memory ability in patients with TLE, as indicated by poor performance on the Warrington Recognition Memory Test for Faces (RMF), which is commonly used to evaluate visual memory in these patients. However, little is known about whether patients with TLE exhibit difficulties in identifying faces in daily life after ATL. The aim of this study was to investigate facial memory ability and self-awareness of face identification difficulties in patients with TLE after ATL. Sixteen patients with TLE after right ATL, 14 patients with TLE after left ATL, and 29 healthy controls were enrolled in this study. We developed the multiview face recognition test (MFRT), which comprises a learning phase (one or three frontal face images without external facial feature information) and a recognition phase (frontal, oblique, or noise-masked face images). Facial memory abilities were examined in all participants using the MFRT and RMF, and self-awareness of difficulties in face identification was evaluated using the 20-item prosopagnosia index (PI20), which has been widely used to assess developmental prosopagnosia. The MFRT performance in patients with TLE after ATL was significantly worse than that in healthy controls regardless of the resected side, whereas the RMF scores in patients with TLE were significantly worse than those in healthy controls only after right ATL. The MFRT performance in patients with TLE after both left and right ATL was more influenced by working memory load than that in healthy controls. The PI20 scores revealed that patients with TLE after left ATL were aware of their difficulties in identifying faces. These findings suggest that patients with TLE not only after right ATL but also after left ATL might have difficulties in face identification.

Neural correlates of verbal recognition memory in obese adults with and without major depressive disorder.

BackgroundObesity and major depressive disorder (MDD) independently contribute to memory impairment. Little is known about shared neural mechanisms that may result in the cognitive impairment experienced by these populations. This study's aim was to determine how obesity impacts neural activity during a verbal recognition memory task in individuals both with and without MDD.MethodsFunctional magnetic resonance imaging was employed to examine whether differences in neural activation patterns would be seen across three groups during the Warrington's Recognition Memory Test. Three study groups are reported: 20 subjects with obesity but without MDD (bariatric controls), 23 subjects with past or current MDD and obesity, and 20 normal BMI controls (healthy controls).ResultsThree‐group conjunction analyses indicated that overlapping neural regions were activated during both encoding and retrieval processes across all groups. However, second‐level 2‐group t‐contrasts indicated that neural activation patterns differed when comparing healthy and bariatric controls, and when comparing bariatric controls and bariatric MDD participants.DiscussionResults indicate that obesity in conjunction with MDD confers a subtle impact on neural functioning. Given high rates of obesity and MDD comorbidity, and the role of cognition on ability to return to premorbid level of functioning, this association should inform treatment decisions.

A-215 The Utility of the First Ten Items of the Warrington Recognition Memory Test as a Performance Validity Test

Abstract Objective Performance validity tests (PVTs) are widely used in neuropsychological evaluations but are often lengthy and time-consuming. Therefore, development of more efficient PVTs is critical. The current study evaluated the utility of the first 10 items of the Warrington Recognition Memory Test (RMT) as an indicator of performance validity. Methods This study utilized archival data from 134 veterans presenting for a clinical neuropsychological evaluation at a southeastern Veterans Affairs hospital. Patients were deemed “credible” if they failed less than two unrelated PVT measures, had a FSIQ &amp;gt; 70, and did not carry a diagnosis of dementia. This resulted in 103 patients in the credible group [Mage = 49.76(11.67); Meducation = 14.09(2.88); 77.67% Male]. The 31 patients in the non-credible group met Slick et al. (1999) criteria[Mage = 45.13(11.18); Meducation = 12.77(2.53); 87.10% Male]. Frequency counts were run to determine sensitivity and specificity values at established cut-offs and to create new cut-offs for the first 10 items. Results Using established cut-off scores, the RMT total score had adequate specificity (91%) with a corresponding sensitivity of 84%, and the RMT time score had adequate specificity (93%) with a corresponding sensitivity of 34%. When examining the first 10 items on the RMT, a score of &amp;lt; 8 resulted in 96% specificity and 61% sensitivity. Conclusions The established cutoffs for the RMT performed well in this patient sample. Additionally, using a cutoff score of ≤ 8 on the first 10 items of the RMT may be a useful indicator of probable failure on the RMT, significantly reducing test administration time.

Performance validity assessment using response time on the Warrington Recognition Memory Test

Objective The present study tested the incremental utility of response time (RT) on the Warrington Recognition Memory Test – Words (RMT-W) in classifying bona fide versus feigned TBI. Method Participants were 173 adults: 55 with moderate to severe TBI, 69 healthy comparisons (HC) instructed to perform their best, and 49 healthy adults coached to simulate TBI (SIM). Participants completed a computerized version of the RMT-W in the context of a comprehensive neuropsychological battery. Groups were compared on RT indices including mean RT (overall, correct trials, incorrect trials) and variability, as well as the traditional RMT-W accuracy score. Results Several RT indices differed significantly across groups, although RMT-W accuracy predicted group membership more strongly than any individual RT index. SIM showed longer average RT than both TBI and HC. RT variability and RT for incorrect trials distinguished SIM-HC but not SIM-TBI comparisons. In general, results for SIM-TBI comparisons were weaker than SIM-HC results. For SIM-HC comparisons, classification accuracy was excellent for all multivariable models incorporating RMT-W accuracy with one of the RT indices. For SIM-TBI comparisons, classification accuracies for multivariable models ranged from acceptable to excellent discriminability. In addition to mean RT and RT on correct trials, the ratio of RT on correct items to incorrect items showed incremental predictive value to accuracy. Conclusion Findings support the growing body of research supporting the value of combining RT with PVTs in discriminating between verified and feigned TBI. The diagnostic accuracy of the RMT-W can be improved by incorporating RT.

The Oxytocin Receptor Gene (OXTR) and Face Recognition

A recent study has linked individual differences in face recognition to rs237887, a single-nucleotide polymorphism (SNP) of the oxytocin receptor gene (OXTR; Skuse et al., 2014). In that study, participants were assessed using the Warrington Recognition Memory Test for Faces, but performance on Warrington’s test has been shown not to rely purely on face recognition processes. We administered the widely used Cambridge Face Memory Test—a purer test of face recognition—to 370 participants. Performance was not significantly associated with rs237887, with 16 other SNPs of OXTR that we genotyped, or with a further 75 imputed SNPs. We also administered three other tests of face processing (the Mooney Face Test, the Glasgow Face Matching Test, and the Composite Face Test), but performance was never significantly associated with rs237887 or with any of the other genotyped or imputed SNPs, after corrections for multiple testing. In addition, we found no associations between OXTR and Autism-Spectrum Quotient scores.

The Warrington Recognition Memory Test for Words as a Measure of Response Bias: Total Score and Response Time Cutoffs Developed on "Real World" Credible and Noncredible Subjects

Several studies have examined the usefulness of the Warrington Recognition Memory Test-Words as a measure to detect suspect effort, although samples have generally been small and/or comprised of simulators rather than "real world" credible and noncredible patients. The current study examined the Warrington Recognition Memory Test-Words total score and response time of "real world" noncredible patients (as determined by motive to feign, failure on > or =2 independent measures of response bias, low cognitive scores inconsistent with normal ADLs; n = 190) versus credible patients (as determined by no motive to feign, failure of < or =1 measure of response bias; n = 124) derived from an archival database of individuals from the Harbor-UCLA Medical Center, Department of Psychiatry, Outpatient Neuropsychology Service, and the private practice of the second author. Noncredible patients obtained significantly lower total scores and longer times to complete the task. A total correct cutoff of < or =42 was found to have excellent specificity (91.9%) and sensitivity (88.9%), whereas a time cutoff of > or =207'' was associated with 65.5% sensitivity at 90.7% specificity, and when the time cut-score was used in combination with the total score cutoff, an additional 5% of the noncredible participants were captured, raising overall sensitivity to 93.7% (at 87.1% specificity). Thus, the Warrington Recognition Memory Test-Words, although not originally created for the purposes of measuring suspect effort, appears to be an excellent measure for detecting response bias on neuropsychological testing.

The clinical utility of the Warrington Recognition Memory Test in people with a low IQ

The sensitivity of the Warrington Recognition Memory for Faces (RMF) to reliably localize temporal lobe dysfunction in surgical epilepsy candidates is not as strong as that of the Recognition Memory for Words (RMW). Previous research has indicated that its diagnostic utility is improved in patients with lower IQs. Data from 114 patients with unilateral hippocampal sclerosis was retrospectively examined to explore the accuracy of both subtests in patients with IQs within the low average/borderline impaired and intellectual disability ranges. In our group, the RMF did not discriminate between right and left hippocampal sclerosis, whilst the RMW did. However, many patients functioning within the intellectual disability range are unable to complete the RMW. There is a need to develop neuropsychological protocols appropriate for this group.

Assessment of Feigned Cognitive Impairment: A Neuropsychological Perspective

Back to table of contents Previous article Next article Book ReviewFull AccessAssessment of Feigned Cognitive Impairment: A Neuropsychological PerspectiveMichael C. Harlow M.D., J.D.Michael C. Harlow M.D., J.D.Search for more papers by this authorPublished Online:1 Jul 2009https://doi.org/10.1176/ps.2009.60.7.996aAboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail In the book Assessment of Feigned Cognitive Impairment, edited by Kyle Brauer Boone, the authors examine the array of assessment instruments that are used to determine feigned cognitive impairment. Part 1 of the book provides historical and literary examples of malingering to convey its universal nature. The contributors relate how feigned cognitive impairment has developed into an issue of prime significance in mental health and disability evaluations. They also provide a comprehensive overview of current functional neuroimaging studies of deception and malingering. Part 2 of the book addresses techniques and strategies in cognitive effort assessments. The editor postulates that these forms of deception occur on a continuum and that forms of malingering overlap with somatoform disorders—contrary to the current DSM-IV classification system that differentiates malingering and somatoform disorders as mutually exclusive. There is an expansive discussion of forced-choice effort tests and the utility of these tests in helping to determine the likelihood of malingering. Non-forced-choice measures are also discussed, including the Rey-15 Test of Memory and the Rey Word Recognition Test. The book lists an overview of estimated malingering base rates for a variety of medical and neurocognitive conditions. Also discussed are intelligence tests as a measure of effort in assessing cognitive impairment. The authors discuss the utility of intelligence testing in delineating poor effort as a sign of neurocognitive impairment and malingering. They also provide an assessment of the use of standardized memory tests to determine effort that is suspect. Reviewed tests include the Warrington Recognition Memory Test and the Wechsler Memory Scale. The authors compare predictive values of standardized memory tests, concluding that these tests of effort are useful in determining suspect efforts only if they are relied on with other forms of neuropsychological evaluations.Executive functioning measures, motor and sensory tests, and the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) are assessed for their usefulness and limitations in a determination of malingering. Included in the discussion of executive function measures is an in-depth review of the Wisconsin Card Sorting Test. The authors provide extensive evidence that the MMPI-2 is highly valuable in determining feigned cognitive impairment, noting that the MMPI-2 has high predictive value, sensitivity, and specificity.Part 3 of the book reviews neuropsychological testing for feigned cognitive impairment in cases of mild traumatic brain injury, pain- and fatigue-related medical disorders, mental retardation, attention-deficit hyperactivity disorder, and toxin exposures. This part of the book also discusses the challenges of cognitive testing with non-English-speaking and forensic populations. Part 3 concludes with an assessment of the state of cognitive testing instruments and predictions about the future of these tests.This book provides an encompassing review of the various assessments for malingering cognitive impairment. The critique offered on the utility of these assessments is based on a comprehensive review of published research in the field. This book is technically advanced and is most appropriate as a reference for psychiatrists and psychologists who wish to develop expertise in assessing feigned cognitive impairment.The reviewer reports no competing interests.Dr. Harlow is forensic psychiatry fellow, University of California, Davis, Medical Center, Sacramento. FiguresReferencesCited byDetailsCited byValidation of the Test of Memory Malingering in a Clinical Population from Singapore11 July 2020 | International Journal of Forensic Mental Health, Vol. 20, No. 1 Volume 60Issue 7 July, 2009Pages 996-997PSYCHIATRIC SERVICES July 2009 Volume 60 Number 7 Metrics PDF download History Published online 1 July 2009 Published in print 1 July 2009

Memory loss resulting from fornix and septal damage: Impaired supra-span recall but preserved recognition over a 24-hour delay.

Despite increasing evidence that the fornix is important for memory, uncertainty remains about the exact nature of subsequent impairments arising from damage to this tract. This uncertainty is often created by pathology in additional brain structures. The present study involved a young man, DN, who had almost complete bilateral loss of the rostral columns of the fornix and much of the surrounding septum in the left hemisphere following the surgical removal of a cavernous angioma. Quantitative MRI analyses of structure size, normalized to intracranial volume, showed no difference in any of the additional brain regions measured, apart from those areas removed to expose the tumor. DN showed a marked, stable anterograde memory impairment that was still present 4 years postsurgery. In contrast, DN performed within normal levels on most tests of recognition memory. This sparing was most striking when given a 24-hr delay between study and test of the Warrington Recognition Memory Test. This recall/recognition dissociation provides further evidence for neuroanatomical divisions within recognition memory processes.

The Relationship of IQ to Effort Test Performance

The relationship between IQ and nine effort indicators was examined in a sample of 189 neuropsychology clinic outpatients who were not in litigation or attempting to obtain disability. Participants with the lowest IQ (50–59) failed approximately 60% of the effort tests, while patients with an IQ of 60 to 69 failed 44% of effort indicators, and individuals with borderline IQ (70 to 79) exhibited a 17% failure rate. All patients with IQ < 70 failed at least one effort test. Cutoffs for the Warrington Recognition Memory Test (Words) and Finger Tapping maintained the highest specificities in low IQ samples.

Dementia and effort test performance

Research on the performance of patients with dementia on tests of effort is particularly limited. We examined archival data from 214 non-litigating patients with dementia on 18 effort indices derived from 12 tests (WAIS-III/WAIS-R Digit Span and Vocabulary, Dot Counting Test, Warrington Recognition Memory Test–Words, WMS-III Logical Memory, Rey Word Recognition Memory Test, Finger Tapping, b-Test, Rey 15-Item, Test of Memory Malingering, Rey Auditory Verbal Learning Test, and Rey Complex Figure Test). Results indicated that recommended cut-offs for Digit Span indicators (Vocabulary Minus Digit Span and four-digit forward span time score) provided ≥90% specificity across participants, while the majority of other effort tests displayed specificities in the 30–70% range. Analyses of test specificity as a function of Mini Mental Status Examination (MMSE) score and specific dementia diagnosis are provided, as well as adjustments to cut-offs to maintain specificity where feasible.

Recognition, recollection, familiarity and executive function in medicated patients with moderate Parkinson's disease

There is conflicting evidence about whether Parkinson's disease (PD) is associated with deficiencies in recognition memory (RM) and the processes which underlie it, namely recollection (a form of recall) and familiarity (a feeling of memory in the absence of recall). The aims of the current study were to examine forced-choice verbal RM (assessed with the Warrington Recognition memory Test), yes-no RM, recollection, familiarity and executive functioning in 17 patients with moderate PD and 17 healthy volunteers matched for age and premorbid intelligence. We predicted that patients with moderate PD would display a significant recollection deficit on the yes-no RM test, because their strategic memory processing that depends on executive functioning and is necessary for efficient encoding and/or retrieval, was disrupted. In contrast, familiarity memory, which is not dependent on these processes, and forced-choice RM (which is largely dependent on familiarity) should show higher levels of preservation. We also predicted that recollection should be correlated with severity of executive dysfunction. Our findings revealed that the PD patients were as likely to accurately discriminate between targets and distractors as the healthy volunteers on both RM tests. However, the PD patients were significantly less reliant on recollection-driven recognition decisions on the yes-no RM test when compared with the healthy control group. The patients also displayed executive function deficits, but these were not correlated with recollection. The extent to which the PD patients' reliance on familiarity at the expense of recollection is explained by impairments in strategic memory processes/executive function and/or medial temporal lobe retrieval processes needs further exploration.

Hereditary Prosopagnosia: the First Case Series

Prosopagnosia is defined as a specific type of visual agnosia characterised by a discernible impairment in the capacity to recognise familiar people by their faces. We present seven family pedigrees with 38 cases in two to four generations of suspected hereditary prosopagnosia, detected using a screening questionnaire. Men and women are impaired and the anomaly is regularly transmitted from generation to generation in all pedigrees studied. Segregation is best explained by a simple autosomal dominant mode of inheritance, suggesting that loss of human face recognition can occur by the mutation of a single gene. Eight of the 38 affected persons were tested on the Warrington Recognition Memory Test for Faces (RMF; Warrington, 1984), famous and family faces tests, learning tests for internal and external facial features and a measure of mental imagery for face and non-face images. As a group, the eight participants scored significantly below an age- and education-matched comparison group on the most relevant test of face recognition; and all were impaired on at least one of the tests. The results provide compelling evidence for significant genetic contribution to face recognition skills and contribute to the promise offered by the emerging field of cognitive neurogenetics.

Warrington's recognition memory for faces: interpretive strategy and diagnostic utility in temporal lobe epilepsy

Performance on Warrington's Recognition Memory Test for Faces (RMF) is thought to rely largely on the integrity of the right temporal lobe. Epilepsy research, however, has been mixed with respect to the diagnostic utility of the RMF. Based on the psychometric properties of the RMF, we investigated the moderating role of intelligence on test classification accuracy in 53 presurgical patients with temporal lobe epilepsy. Classification accuracy rates were poor for the entire sample, but when the sample was divided based on IQ, classification statistics showed a strong degree of diagnostic utility for the RMF among patients with lower IQ levels versus those with higher IQ levels. These findings support the diagnostic utility of the RMF in epilepsy and underscore the moderating role of intelligence on RMF performance.

Neural correlates of episodic encoding and recognition of words in unmedicated patients during an acute episode of schizophrenia: a functional MRI study.

Memory impairment has been well documented in schizophrenia. In a previous study, the authors investigated patterns of brain activity during episodic encoding and recognition of words in remitted, stable schizophrenia outpatients being treated with novel antipsychotics. The same procedure was used in this study to investigate unmedicated patients during an acute episode of schizophrenia. Functional magnetic resonance imaging was used to study regional brain activation in 10 unmedicated patients experiencing an acute episode of schizophrenia and 10 healthy comparison subjects during performance of a modified version of the words subtest of Warrington's Recognition Memory Test. Despite intact recognition performance, patients with schizophrenia showed reduced activation of anterior prefrontal, posterior cingulate, and retrosplenial areas relative to comparison subjects during word encoding. During word recognition, reduced activation was found in the patients' dorsolateral prefrontal and limbic/paralimbic regions. On the other hand, higher metabolism in bilateral anterior prefrontal cortices was observed. The results suggest that different neural pathways are engaged during episodic encoding and recognition of words in patients experiencing an acute episode of schizophrenia relative to healthy comparison subjects. Furthermore, acute psychosis may prevent practice effects, reflected in a failure to engage brain regions associated with successful episodic memory retrieval in healthy subjects.