Choroid plexus volumes and auditory verbal learning scores are associated with conversion from mild cognitive impairment to Alzheimer's disease.

PURPOSE: Mild cognitive impairment (MCI) can be the prodromal phase of Alzheimer's disease (AD) where appropriate intervention might prevent or delay conversion to AD. Given this, there has been increasing interest in using magnetic resonance imaging (MRI) and neuropsychological testing to predict conversion from MCI to AD. Recent evidence suggests that the choroid plexus (ChP), neural substrates implicated in brain clearance, undergo volumetric changes in MCI and AD. Whether the ChP is involved in memory changes observed in MCI and can be used to predict conversion from MCI to AD has not been explored. METHOD: The current study used data from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database to investigate whether later progression from MCI to AD (progressive MCI [pMCI], n = 115) or stable MCI (sMCI, n = 338) was associated with memory scores using the Rey Auditory Verbal Learning Test (RAVLT) and ChP volumes as calculated from MRI. Classification analyses identifying pMCI or sMCI group membership were performed to compare the predictive ability of the RAVLT and ChP volumes. FINDING: The results indicated a significant difference between pMCI and sMCI groups for right ChP volume, with the pMCI group showing significantly larger right ChP volume (p = .01, 95% confidence interval [-.116, -.015]). A significant linear relationship between the RAVLT scores and right ChP volume was found across all participants, but not for the two groups separately. Classification analyses showed that a combination of left ChP volume and auditory verbal learning scores resulted in the most accurate classification performance, with group membership accurately predicted for 72% of the testing data. CONCLUSION: These results suggest that volumetric ChP changes appear to occur before the onset of AD and might provide value in predicting conversion from MCI to AD.

Dissociating memory and executive function impairment through temporal features in a word list verbal learning task.

The Rey Auditory Verbal Learning Test (RAVLT) is an established verbal learning test commonly used to quantify memory impairments due to Alzheimer's Disease (AD) both at a clinical dementia stage or prodromal stage of mild cognitive impairment (MCI). Focal memory impairment-as quantified e.g. by the RAVLT-at an MCI stage is referred to as amnestic MCI (aMCI) and is often regarded as the cognitive phenotype of prodromal AD. However, recent findings suggest that not only learning and memory but also other cognitive domains, especially executive functions (EF) and processing speed (PS), influence verbal learning performance. This research investigates whether additional temporal features extracted from audio recordings from a participant's RAVLT response can better dissociate memory and EF in such tasks and eventually help to better describe MCI subtypes. 675 age-matched participants from the H70 Swedish birth cohort were included in this analysis; 68 participants were classified as MCI (33 aMCI and 35 due to executive impairment). RAVLT performances were recorded and temporal features extracted. Novel temporal features were correlated with established neuropsychological tests measuring EF and PS. Lastly, the downstream diagnostic potential of temporal features was estimated using group differences and a machine learning (ML) classification scenario. Temporal features correlated moderately with measures of EF and PS. Performance of an ML classifier could be improved by adding temporal features to traditional counts. We conclude that RAVLT temporal features are in general related to EF and that they might be capable of dissociating memory and EF in a word list learning task.

Neuropsychiatric outcomes following strokes involving the cerebellum: a retrospective cohort study.

Introduction: Given the wide-ranging involvement of cerebellar activity in motor, cognitive, and affective functions, clinical outcomes resulting from cerebellar damage can be hard to predict. Cerebellar vascular accidents are rare, comprising less than 5% of strokes, yet this rare patient population could provide essential information to guide our understanding of cerebellar function. Methods: To gain insight into which domains are affected following cerebellar damage, we retrospectively examined neuropsychiatric performance following cerebellar vascular accidents in cases registered on a database of patients with focal brain injuries. Neuropsychiatric testing included assessment of cognitive (working memory, language processing, and perceptual reasoning), motor (eye movements and fine motor control), and affective (depression and anxiety) domains. Results: Results indicate that cerebellar vascular accidents are more common in men and starting in the 5th decade of life, in agreement with previous reports. Additionally, in our group of twenty-six patients, statistically significant performance alterations were not detected at the group level an average of 1.3 years following the vascular accident. Marginal decreases in performance were detected in the word and color sub-scales of the Stroop task, the Rey Auditory Verbal Learning Test, and the Lafayette Grooved Pegboard Test. Discussion: It is well established that the acute phase of cerebellar vascular accidents can be life-threatening, largely due to brainstem compression. In the chronic phase, our findings indicate that recovery of cognitive, emotional, and affective function is likely. However, a minority of individuals may suffer significant long-term performance impairments in motor coordination, verbal working memory, and/or linguistic processing.

Methylation of BDNF gene in association with episodic memory in women.

Brain-derived neurotrophic factor (BDNF) gene regulation plays an important role in long-term memory formation, and the DNA methylation (DNAm) level of BDNF promoters has been associated with episodic memory deficits. Our aim was to explore the association between DNAm levels in BDNF promoter IV with verbal learning and memory performance in healthy women. We conducted a cross-sectional study by recruiting 53 individuals. Episodic memory was assessed by using the Rey Auditory Verbal Learning Test (RAVLT). Clinical interviews, RAVLT, and blood sample collection were assessed in all participants. DNAm was measured on DNA from whole peripheral blood using pyrosequencing. According to generalized linear model (GzLM) analyses, cytosine guanine dinucleotide (CpG) site 5 showed significant associations between learning capacity (LC, p < 0.035), that is, every 1% of DNA methylation at CpG site 5 results in a 0.068 reduction in verbal learning performance. To the best of our knowledge, the current study is the first to show that BDNF DNAm plays an important role in episodic memory.

Improving Amnesia Diagnostic Accuracy with RAVLT Single Scores and Composite Indices: Italian Normative Data.

OBJECTIVE: The Rey Auditory Verbal Learning Test (RAVLT) is a widely used verbal memory measure that provides scores for different aspects of memory. It involves repeated auditory presentation and recall of a 15-item word list (List A) followed by presentation and recall of a distractor list (List B) and then un-cued immediate and delayed recalls (at 15 min and 1 week) of List A as well as recognition testing. Aims of this study are to provide Italian normative data for certain RAVLT Scores and Composite Indices to improve the diagnostic accuracy of the test in clinical settings and to provide further evidence on how RAVLT can differentiate different amnesia profiles due to focal lesions. METHODS: We enrolled 440 healthy participants and RAVLT Single Scores and Composite Indices have been analyzed by means of multiple regression to verify the influence of age, education, and gender. RESULTS: We computed the best linear models with RAVLT Single Scores and Composite Indices, as dependent variables, and the most suitable transformation of independent variables. By reversing the signs of the regression coefficients, the adjustment factors for each level of age and, if needed, education and gender have been computed and the adjusted scores have been standardized into Equivalent Scores. CONCLUSION: Using these standardized measures, we differentiate three profiles of amnesia due to selective hippocampal sclerosis with severe encoding deficit, fornix lesions with source memory problems, and temporal lobe epilepsy with consolidation failure.

The Contribution of Working Memory Areas to Verbal Learning and Recall in Primary Progressive Aphasia.

Recent evidence of domain-specific working memory (WM) systems has identified the areas and networks which are involved in phonological, orthographic, and semantic WM, as well as in higher level domain-general WM functions. The contribution of these areas throughout the process of verbal learning and recall is still unclear. In the present study, we asked, what is the contribution of domain-specific specialized WM systems in the course of verbal learning and recall? To answer this question, we regressed the perfusion data from pseudo-continuous arterial spin labeling (pCASL) MRI with all the immediate, consecutive, and delayed recall stages of the Rey Auditory Verbal Learning Test (RAVLT) from a group of patients with Primary Progressive Aphasia (PPA), a neurodegenerative syndrome in which language is the primary deficit. We found that the early stages of verbal learning involve the areas with subserving phonological processing (left superior temporal gyrus), as well as semantic WM memory (left angular gyrus, AG_L). As learning unfolds, areas with subserving semantic WM (AG_L), as well as lexical/semantic (inferior temporal and fusiform gyri, temporal pole), and episodic memory (hippocampal complex) become more involved. Finally, a delayed recall depends entirely on semantic and episodic memory areas (hippocampal complex, temporal pole, and gyri). Our results suggest that AG_L subserving domain-specific (semantic) WM is involved only during verbal learning, but a delayed recall depends only on medial and cortical temporal areas.

Validation and Normative Data of the Spanish Version of the Rey Auditory Verbal Learning Test and Associated Long-Term Forgetting Measures in Middle-Aged Adults.

Rey Auditory Verbal Learning Test (RAVLT) is an episodic memory helpful measure to detect changes associated with abnormal aging. There is a lack of RAVLT validation and normalization studies in Spain. The aim was to determine its psychometric properties and explore long-term forgetting (LTF) performance through 1-week delayed recall under three different modes of administration. The RAVLT was administered to 602 cognitively healthy volunteers, aged between 41 and 65 years, of whom 251 completed the LTF assessment. Findings reveal a factorial structure of four components, with satisfactory goodness of fit, and adequate convergent and divergent validity. We also demonstrated the differential effect of three methodologies used in LTF assessment, supporting that test expectancy positively influences long-term storage. Finally, normative data were generated according to age, sex, and education. The test, including the LTF measure, is a promising tool to estimate memory in middle-aged adults and develop predictive brain aging models.

Clinical relevance of the radiation dose bath in lower grade glioma, a cross-sectional pilot study on neurocognitive and radiological outcome.

Aim: To investigate the clinical relevance of the radiotherapy (RT) dose bath in patients treated for lower grade glioma (LGG). Methods: Patients (n = 17) treated with RT for LGG were assessed with neurocognitive function (NCF) tests and structural Magnetic Resonance Imaging (MRI) and categorized in subgroups based on tumour lateralisation. RT dose, volumetric results and cerebral microbleed (CMB) number were extracted for contralateral cerebrum, contralateral hippocampus, and cerebellum. The RT clinical target volume (CTV) was included in the analysis as a surrogate for focal tumour and other treatment effects. The relationships between RT dose, CTV, NCF and radiological outcome were analysed per subgroup. Results: The subgroup with left-sided tumours (n = 10) performed significantly lower on verbal tests. The RT dose to the right cerebrum, as well as CTV, were related to poorer performance on tests for processing speed, attention, and visuospatial abilities, and more CMB.In the subgroup with right-sided tumours (n = 7), RT dose in the left cerebrum was related to lower verbal memory performance, (immediate and delayed recall, r = -0.821, p = 0.023 and r = -0.937, p = 0.002, respectively), and RT dose to the left hippocampus was related to hippocampal volume (r = -0.857, p = 0.014), without correlation between CTV and NCF. Conclusion: By using a novel approach, we were able to investigate the clinical relevance of the RT dose bath in patients with LGG more specifically. We used combined MRI-derived and NCF outcome measures to assess radiation-induced brain damage, and observed potential RT effects on the left-sided brain resulting in lower verbal memory performance and hippocampus volume.

Relationship of sex differences in cortical thickness and memory among cognitively healthy subjects and individuals with mild cognitive impairment and Alzheimer disease.

BACKGROUND: An aging society has increased rates of late onset Alzheimer disease dementia (ADD), the most common form of age-related dementia. This neurodegenerative disease disproportionately affects women. METHODS: We use data from the Alzheimer's Disease Neuroimaging Initiative (ADNI) to examine sex differences in cortical thickness (CT) and memory performance. Analyses of covariance (ANCOVA) models were used to examine effects of sex and diagnosis (DX) on CT and verbal memory. For regions demonstrating significant interaction effects of sex and DX, we tested whether sex moderated cognition-thickness relationships. We used machine learning as a complementary method to explore multivariate CT differences between women and men. RESULTS: Women demonstrated greater CT in many brain regions. More specifically, men showed relatively consistent CT declines in all stages, from normal control (NC) to ADD in the bilateral cingulate cortex, bilateral temporal regions, and left precuneus; women had more stable CT in these regions between NC and mild cognitive impairment (MCI) stages, but sharper declines from MCI to ADD. Similarly, for the Rey Auditory Verbal Learning Test (RAVLT), ANCOVA analyses showed that women had significantly better immediate and delayed recall scores than men, at NC and MCI stages, but greater differences, cross-sectionally, from MCI to ADD than men. We found significant sex moderation effects between RAVLT-immediate scores and CT of right isthmus-cingulate for all subjects across DX. Partial correlation analyses revealed that increased CT of right isthmus-cingulate was associated with better verbal learning in women, driven by positron emission tomography defined amyloid positive (Aß+) subjects. Significant sex-moderation effects in cognition-thickness relationships were further found in the right middle-temporal, left precuneus, and left superior temporal regions in Aß+ subjects. Using a machine learning approach, we investigated multivariate CT differences between women and men, showing an accuracy in classification of 75% for Aß+ cognitively NC participants. CONCLUSIONS: Sex differences in memory and CT can play a key role in the different vulnerability and progression of ADD in women compared to men. Machine learning indicates sex differences in CT are most relevant early in the ADD neurodegeneration.

Validation of the SCAT5 and Child SCAT5 Word-List Memory Task.

The Sports Concussion Assessment Tool-5th Edition (SCAT5) and the child version (Child SCAT5) are the current editions of the SCAT and have updated the memory testing component from previous editions. This study aimed to validate this new memory component against the Rey Auditory Verbal Learning Test (RAVLT) as the validated standard. This prospective, observational study, carried out within The Royal Children's Hospital Emergency Department, Melbourne, Australia, recruited 198 participants: 91 with concussion and 107 upper limb injury or healthy sibling controls. Partial Pearson correlations showed that memory acquisition and recall on delay aspects of the SCAT5 were significantly correlated with the RAVLT equivalents when controlling for age (p < 0.001, r = 0.565 and p < 0.001, r = 0.341, respectively). Factor analysis showed that all RAVLT and SCAT5 memory components load on to the same factor, accounting for 59.13% of variance. Logistic regression models for both the RAVLT and SCAT5, however, did not predict group membership (p > 0.05). Receiver operating curve analysis found that the area under the curve for all variables and models was below the recommended 0.7 threshold. This study demonstrated that the SCAT5 and Child SCAT5 memory paradigm is a valid measure of memory in concussed children.

Cross-validation of RAVLT performance validity indicators and the RAVLT/RO discriminant function in a large known groups sample.

OBJECTIVE: To cross-validate RAVLT performance validity cut-offs and the RAVLT/RO discriminant function in a large neuropsychological sample. METHOD: RAVLT scores and the RAVLT/RO discriminant function were compared in credible (n = 100) and noncredible (n = 353) neuropsychology referrals. RESULTS: Noncredible patients scored lower than credible patients on RAVLT scores and the RAVLT/RO discriminant function. With cut-offs set to ≥90% specificity, highest sensitivities were observed for the discriminant function (cut-off ≤.064; 55.8%), recognition total (cut-off ≤9; 53.1%), the recognition combination score (≤10; 47.7%), and total learning across trials (cut-off ≤31; 45.3%). Individuals with histories of learning difficulties were over-represented in the 10% of credible patients exceeding cut-offs. When these individuals were removed, cut-offs could be tightened while still maintaining at least 90% specificity, and thereby increasing sensitivity (e.g., recognition total cut-off ≤10, 65% sensitivity; RAVLT/RO discriminant function cut-off ≤.176, 58% sensitivity). When three of the most sensitive, non-overlapping scores were considered in combination, 17% of credible patients failed ≥1 of the three cut-offs, while 3% failed two, and only 1% failed all three. In contrast, in the noncredible sample, more than two-thirds failed one or more of the three cut-offs, nearly half failed ≥2, and nearly a quarter failed all three. CONCLUSIONS: RAVLT PVT cut-offs and the RAVLT/RO discriminant function achieve approximately 50% sensitivity, and approach 65% sensitivity when cut-offs specific to samples without histories of learning problems are employed, confirming that RAVLT cut-offs and the RAVLT/RO discriminant function continue to be valuable techniques in the identification of performance invalidity.

Effect of Hypertension Duration and Blood Pressure Control During Early Adulthood on Cognitive Function in Middle Age.

BACKGROUND: Elevated blood pressure (BP) is a risk factor for cognitive impairment. OBJECTIVE: We aim to explore the association between the duration of hypertension in early adulthood, with cognitive function in midlife. Furthermore, we investigate whether this asssociation is altered among participants with controlled BP. METHODS: This prospective study included 2,718 adults aged 18-30 years without hypertension at baseline who participated in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. Duration of hypertension was calculated based on repeat measurements of BP performed at 2, 5, 7, 10, 15, 20, and 25 years after baseline. Cognitive function was assessed at Year-25 using the Rey Auditory Verbal Learning Test (RAVLT), Digit Symbol Substitution Test (DSST), and Stroop test. RESULTS: After multivariable adjustment, a longer hypertension duration was associated with worse verbal memory (RAVLT, p trend = 0.002) but not with processing speed (DSST, p trend = 0.112) and executive function (Stroop test, p trend = 0.975). Among subgroups of participants with controlled (BP < 140/90 mmHg) and uncontrolled (SBP≥140 mmHg or DBP≥90 mmHg) BP at the time of cognitive assessment (i.e., Year-25 BP), longer duration of hypertension was associated with worse verbal memory. Similar results were observed in subgroups with controlled and uncontrolled average BP prior to cognitive assessment. CONCLUSION: Longer duration of hypertension during early adulthood is associated with worse verbal memory in midlife regardless of current or long-term BP control status. The potential risk of hypertension associated cognitive decline should not be overlooked in individuals with a long duration of hypertension, even if BP levels are controlled.

Word Meaning Contributes to Free Recall Performance in Supraspan Verbal List-Learning Tests.

Supraspan verbal list-learning tests, such as the Rey Auditory Verbal Learning Test (RAVLT), are classic neuropsychological tests for assessing verbal memory. In this study, we investigated the impact of the meaning of the words to be learned on three memory stages [short-term recall (STR), learning, and delayed recall (DR)] in a cohort of 447 healthy adults. First, we compared scores obtained from the RAVLT (word condition) to those of an alternative version of this test using phonologically similar but meaningless items (pseudoword condition) and observed how each score varied as a function of age and sex. Then, we collected the participants' self-reported strategies to retain the word and pseudoword lists and examined if these strategies mediated the age and sex effects on memory scores. The word condition resulted in higher memory scores than pseudoword condition at each memory stage and even canceled out, for the learning stage, the detrimental effect of age that was observed for the short-term and DR. When taking sex into account, the word advantage was observed only in women for STR. The self-reported strategies, which were similar for words and pseudowords, were based on the position of the item on the list (word: 53%, pseudoword: 37%) or the meaning of the item (word: 64%, pseudoword: 58%) and were used alone or in combination. The best memory performance was associated with the meaning strategy in the word condition and with the combination of the meaning and position strategies in the pseudoword condition. Finally, we found that the word advantage observed in women for STR was mediated by the use of the meaning strategy. The RAVLT scores were thus highly dependent on word meaning, notably because it allowed efficient semantic knowledge-based strategies. Within the framework of Tulving's declarative memory model, these results are at odds with the depiction of the RAVLT as a verbal episodic memory test as it is increasingly referred to in the literature.

The mediating role of hippocampal networks on stress regulation in amnestic mild cognitive impairment.

OBJECTIVES: To examine the role of the hippocampus in stress regulation in older adults with amnestic mild cognitive impairment (aMCI). METHODS: This study combined resting-state functional MRI, structural MRI, self-reported chronic stress exposure, and an electrocardiography-based acute stress protocol to compare aMCI group (n = 17) to their cognitively healthy counterparts (HC, n = 22). RESULTS: For the entire sample, there was a positive correlation between chronic stress exposure and acute stress regulation. The aMCI group showed significantly smaller volumes in the right hippocampus than HC. The two groups did not differ in chronic stress exposure or acute stress regulation. In the HC group, the left hippocampal connectivity with inferior parietal lobe was significantly correlated with both the chronic stress and acute stress. In the aMCI group, the left hippocampal connectivity with both the right insula and the left precentral gyrus was significantly correlated to chronic stress exposure and acute stress regulation. Additionally, the left hippocampal connectivity with right insula significantly mediated the relationship between chronic stress exposure and acute stress regulation in aMCI group. CONCLUSIONS: Extra hippocampal networks may be recruited as compensation to attend the maintenance of relatively normal stress regulation in aMCI by alleviating the detrimental effects of chronic stress exposure on acute stress regulation.

Functional disconnectivity of the hippocampal network and neural correlates of memory impairment in treatment-resistant depression.

BACKGROUND: Major depressive disorder (MDD) is a disabling neuropsychiatric condition associated with cognitive impairment. Neuroimaging studies have consistently linked memory deficits with hippocampal atrophy in MDD patients. However, there has been a paucity of research examining how the hippocampus functionally contributes to memory impairments in MDD. The present study examined whether hippocampal networks distinguish treatment-resistant depression (TRD) patients from healthy controls (HCs), and whether these networks underlie declarative memory deficits in TRD. We hypothesized that functional connectivity (FC) of the posterior hippocampus would correlate preferentially with memory in patients, whereas FC pattern of the anterior and intermediate hippocampus would correlate with emotion-mediated regions and show a significant correlation with memory. METHODS: Resting-state functional magnetic resonance imaging (fMRI) scans were acquired in 56 patients and 42 age- and sex-matched HCs. We parcellated the hippocampus into three subregions based on a sparse representation-based method recently developed by our group. FC networks of hippocampal subregions were compared between patients and HCs and correlated with clinical measures and cognitive performance. RESULTS: Decreased connectivity of the right intermediate hippocampus (RIH) with the limbic regions was a distinguishing feature between TRD and HCs. These functional abnormalities were present in the absence of structural volumetric differences. Furthermore, lower right amygdalar connectivity to the RIH related to a longer current depressive episode. Declarative memory deficits in TRD were significantly associated with left posterior and right intermediate hippocampal FC patterns. LIMITATIONS: Our patient samples were treatment-resistant, the conclusions from this study cannot be generalized to all MDD patients directly. Task-based imaging studies are needed to demonstrate hippocampal engagement in the memory deficits of patients. Finally, our findings are strongly in need of replication in independent validation samples. CONCLUSIONS: These findings demonstrate a transitional property of the intermediate hippocampal subregion between its anterior and posterior counterparts in TRD patients, and provide new insights into the neural network-level dysfunction of the hippocampus in TRD.

Executive functioning in cognitively normal middle-aged offspring of late-onset Alzheimer's disease patients.

Episodic memory deficits are traditionally seen as the hallmark cognitive impairment during the prodromal continuum of late-onset Alzheimer's disease (LOAD). Previous studies identified early brain alterations in regions subserving executive functions in asymptomatic, middle-aged offspring of patients with LOAD (O-LOAD), suggesting that premature episodic memory deficits could be associated to executive dysfunction in this model. We hypothesized that O-LOAD would exhibit reduced executive performance evidenced by increased errors and decreased strategy use on an episodic memory task. We assessed 32 asymptomatic middle-aged O-LOAD and 28 age-equivalent control subjects (CS) with several tests that measure executive functions and the Rey Auditory Verbal Learning Test (RAVLT) to measure memory performance. All tests were scored using both traditional and process scores (quantification of errors and strategies underlying overall performance). T-tests were used to compare performance between both groups and Spearman correlations were implemented to measure associations between variables. O-LOAD participants exhibited decreased executive performance compared to CS as it relates to initiation time (Tower of London), mental switching (Trail Making Test B), and interference effects (Stroop Word-Color condition). Traditional RAVLT measures showed a poorer performance by O-LOAD and RAVLT process scores revealed increased interference effects on this group. Positive correlations (rs) were found between the executive measures and several RAVLT measures for O-LOAD but not for CS. In conclusion, O-LOAD participants exhibited early subtle cognitive changes in executive processing. Observed memory difficulties may be associated in part to executive deficits suggesting an interplay between memory and executive functions. Process score impairments were observed earlier than clinical decline on neuropsychological scores in this at-risk cohort and might be useful cognitive markers of preclinical LOAD.

Experimental effects of acute exercise on episodic memory acquisition: Decomposition of multi-trial gains and losses.

OBJECTIVE: Research demonstrates that acute exercise may enhance retention of multi-trial episodic memories. Previous work has examined the effects of exercise on the mean level of memory recall. However, no study has examined whether exercise can influence the acquisition of new items, which was the purpose of this experiment. METHODS: Using a randomized controlled trial design, participants (young adults; Mage=22yrs) completed either a high-intensity bout of treadmill exercise for 15-min (n=22) or sat (n=22) prior to completing a multi-trial episodic memory task. This task involved recalling 15 words for six successive trials, as well as after a 20-min delay (Trial 7). The performance on the multiple trials was categorized into gains (items not recalled on Trial n that were recalled on Trial n+1) and losses (items recalled on Trial n that were not recalled on Trial n+1). RESULTS: The exercise group recalled more words on Trial 6 (11.4 vs. 9.7; P=0.009) and after the 20-min delay (10.9 vs. 9.4; P=0.01). The exercise group (vs. control) had a smaller proportion of losses from Trial 3-4 (10.4% vs. 20.3%; P=0.04) and had a greater proportion of gains from Trial 5-6 (38.5% vs. 14.8%; P=0.01). CONCLUSIONS: The exercise-induced multi-trial memory effect may be influenced by greater item gains.

Does subjective improvement in adults with intracranial arachnoid cysts justify surgical treatment?

OBJECTIVE Subjective improvement of patients who have undergone surgery for intracranial arachnoid cysts has justified surgical treatment. The current study aimed to evaluate the outcome of surgical treatment for arachnoid cysts using standardized interviews and assessments of neuropsychological function and balance. The relationship between arachnoid cyst location, postoperative improvement, and arachnoid cyst volume was also examined. METHODS The authors performed a prospective, population-based study. One hundred nine patients underwent neurological, neuropsychological, and physiotherapeutic examinations. The arachnoid cysts were considered symptomatic in 75 patients, 53 of whom agreed to undergo surgery. In 32 patients, results of the differential diagnosis revealed that the symptoms were due to a different underlying condition and were unrelated to an arachnoid cyst. Neuropsychological testing included target reaction time, Grooved Pegboard, Rey Auditory Verbal Learning, Rey Osterrieth complex figure, and Stroop tests. Balance tests included the extended Falls Efficacy Scale, Romberg, and sharpened Romberg with open and closed eyes. The tests were repeated 5 months postoperatively. Cyst volume was pre- and postoperatively measured using OsiriX software. RESULTS Patients who underwent surgery did not have results on balance and neuropsychological tests that were different from patients who declined or had symptoms unrelated to the arachnoid cyst. Patients with a temporal arachnoid cyst performed within the normal range on the neuropsychological tests. Seventy-seven percent of the patients who underwent surgery reported improvement, yet there were no differences in test results before and after surgery. Arachnoid cysts in the temporal region and posterior fossa did not influence the preoperative results of neuropsychological and motor tests. The arachnoid cyst volume decreased postoperatively (p < 0.0001), but there was no relationship between volume reduction and clinical improvement. CONCLUSIONS The results of this study speak against objectively verifiable improvement following surgical treatment in adults with intracranial arachnoid cysts.

The effect of cranioplasty following decompressive craniectomy on cerebral blood perfusion, neurological, and cognitive outcome.

OBJECTIVE Decompressive craniectomy is an established therapy for refractory intracranial hypertension. Cranioplasty following decompressive craniectomy not only provides protection to the brain along with cosmetic benefits, but also enhances rehabilitation with meaningful functional recovery of potentially reversible cortical and subcortical damaged areas of the affected as well as the contralateral hemisphere. The aim of the study was to assess neurological and cognitive outcome as well as cerebral blood flow after cranioplasty. METHODS Thirty-four patients admitted for replacement cranioplasty after decompressive craniectomy for head injury were studied prospectively. Clinical, neurological, and cognitive outcomes were assessed by the Glasgow Outcome Scale (GOS), the Glasgow Coma Scale, and a battery of cognitive tests, respectively. Simultaneously, cerebral blood perfusion was assessed by technetium-99m ethyl cysteinate dimer (99mTc-ECD) brain SPECT imaging 7 days prior to and 3 months after cranioplasty. RESULTS Prior to cranioplasty 9 patients (26.5%) had GOS scores of 5 and 25 patients (73.5%) had GOS scores of 4, whereas postcranioplasty all 34 patients (100%) improved to GOS scores of 5. Approximately 35.3%-90.9% patients showed cognitive improvement postcranioplasty in various tests. Also, on comparison with brain SPECT, 94% of patients showed improvement in cerebral perfusion in different lobes. CONCLUSIONS Cranioplasty remarkably improves neurological and cognitive outcomes supported by improvement in cerebral blood perfusion.

Temporal Effects of Acute Walking Exercise on Learning and Memory Function.

PURPOSE: To evaluate the temporal effects of acute exercise on episodic memory. DESIGN: A quasi-experimental study. SAMPLE: Eighty-eight college students (N = 22 per group). MEASURES: Four experimental groups were evaluated, including a control group, exercising prior to memory encoding, exercising during encoding, and exercising during memory consolidation. The exercise stimulus consisted of a 15-minute moderate-intensity walk on a treadmill. Participants completed the Rey Auditory Verbal Learning Test (RAVLT) to assess learning and memory. Prospective memory was assessed via a Red Pen Task. Long-term memory (recognition and attribution) of the RAVLT was assessed 20 minutes and 24 hours after exercise. ANALYSIS: Repeated-measures analysis of variance (ANOVA) assessed the performance of RAVLT scores of trials 1 to 5 across groups. One-way ANOVA assessed the performance of individual trials across groups, whereas χ2 assessed the performance of the Red Pen Task across groups. RESULTS: Regarding learning, the interaction of groups × trial was marginally statistically significant ( F12,332 = 1.773, P = .05), indicating that the group which exercised before encoding did better than the group that exercised during encoding and consolidation. For both 24-hour recognition and attribution performance, the group that exercised before memory encoding performed significantly better than the group that exercised during consolidation ( P = .05 recognition, P = .006 attribution). DISCUSSION: Engaging in a 15-minute bout of moderate-intensity walking before a learning task was effective in influencing long-term episodic memory.