Impaired List Learning Is Not a General Property of Frontal Lesions

2009 ◽  
Vol 21 (7) ◽  
pp. 1422-1434 ◽  
Author(s):  
Michael P. Alexander ◽  
Donald Stuss ◽  
Susan Gillingham
Keyword(s):  
General Property ◽  
Memory Performance ◽  
Small Sample ◽  
Group Differences ◽  
Task Structure ◽  
Significant Group ◽  
List Learning ◽  
Small Sample Sizes ◽  
Almost All ◽  
Frontal Lesions

Background: List-learning tasks are frequently used to provide measures of “executive functions” that are believed necessary for successful memory performance. Small sample sizes, confounding anomia, and incomplete representation of all frontal regions have prevented consistent demonstration of distinct regional frontal effects on this task. Objective: To confirm specific effects of lesions in different frontal regions. Subjects: Forty-one patients with chronic focal frontal lesions and 38 control subjects. There were no group differences in naming scores. Methods: Two word lists were presented, one with unblocked words from related categories and one in a preblocked format. Standard measures of learning, recall, recognition, and strategies were obtained, first for the frontal group as a whole and then for large but defined frontal regions. For all measures with significant group differences, a lesion “hotspotting” method identified possible specific regional injury effects. Results: The frontal group was impaired on almost all measures, but impairments on most measures were particularly identified with lesions in the left superior frontal lobe (approximately area 9s) and some deficits in learning processes were surprisingly more prominent on the blocked list. Conclusion: Difficulty with list learning is not a general property of all frontal lesions. Lesions in different frontal regions impair list learning through specific mechanisms, and these effects may be modified by manipulations of the task structure.

Statistics for Small Groups: The Power of the Pretest

1988 ◽  
Vol 13 (3) ◽  
pp. 142-146 ◽  
Author(s):  
David A. Cole
Keyword(s):  
Statistical Power ◽  
Change Score ◽  
Small Sample ◽  
Analysis Of Covariance ◽  
Small Samples ◽  
Group Differences ◽  
Control Group ◽  
Small Sample Sizes ◽  
Almost All ◽  
Treatment Control Group

In the area of severe-profound retardation, researchers are faced with small sample sizes. The question of statistical power is critical. In this article, three commonly used tests for treatment-control group differences are compared with respect to their relative power: the posttest-only approach, the change-score approach, and an analysis of covariance (ANCOVA) approach. In almost all cases, the ANCOVA approach is the more powerful than the other two, even when very small samples are involved. Finally, a fourth approach involving ANCOVA plus alternate rank assignments is examined and found to be superior even to the ANCOVA approach, especially in small sample cases. Use of slightly more sophisticated statistics in small sample research is recommended.

scholarly journals Characterizing the Urban Mine—Simulation-Based Optimization of Sampling Approaches for Built-in Batteries in WEEE

Recycling ◽  
2020 ◽  
Vol 5 (3) ◽  
pp. 19
Author(s):  
Paul Martin Mählitz ◽  
Nathalie Korf ◽  
Kristine Sperlich ◽  
Olivier Münch ◽  
Matthias Rösslein ◽  
...  
Keyword(s):  
Small Sample ◽  
Data Sets ◽  
Distributed Data ◽  
Sample Sizes ◽  
Representative Sampling ◽  
Comprehensive Knowledge ◽  
Simulation Based ◽  
Using Data ◽  
Small Sample Sizes ◽  
Almost All

Comprehensive knowledge of built-in batteries in waste electrical and electronic equipment (WEEE) is required for sound and save WEEE management. However, representative sampling is challenging due to the constantly changing composition of WEEE flows and battery systems. Necessary knowledge, such as methodologically uniform procedures and recommendations for the determination of minimum sample sizes (MSS) for representative results, is missing. The direct consequences are increased sampling efforts, lack of quality-assured data, gaps in the monitoring of battery losses in complementary flows, and impeded quality control of depollution during WEEE treatment. In this study, we provide detailed data sets on built-in batteries in WEEE and propose a non-parametric approach (NPA) to determine MSS. For the pilot dataset, more than 23 Mg WEEE (6500 devices) were sampled, examined for built-in batteries, and classified according to product-specific keys (UNUkeys and BATTkeys). The results show that 21% of the devices had battery compartments, distributed over almost all UNUkeys considered and that only about every third battery was removed prior to treatment. Moreover, the characterization of battery masses (BM) and battery mass shares (BMS) using descriptive statistical analysis showed that neither product- nor battery-specific characteristics are given and that the assumption of (log-)normally distributed data is not generally applicable. Consequently, parametric approaches (PA) to determine the MSS for representative sampling are prone to be biased. The presented NPA for MSS using data-driven simulation (bootstrapping) shows its applicability despite small sample sizes and inconclusive data distribution. If consistently applied, the method presented can be used to optimize future sampling and thus reduce sampling costs and efforts while increasing data quality.

scholarly journals A-208 The Effect of Language on Invalid Baselines in ImPACT

2020 ◽  
Vol 35 (6) ◽  
pp. 1003-1003
Author(s):  
Kuwabara H ◽  
Grant K ◽  
Moore S ◽  
Maietta J ◽  
Kinsora T ◽  
...  
Keyword(s):  
Cognitive Abilities ◽  
Small Sample ◽  
Cognitive Testing ◽  
English Speakers ◽  
Group Differences ◽  
Language Abilities ◽  
Chi Square ◽  
Impact Performance ◽  
Baseline Testing ◽  
Small Sample Sizes

Abstract Objective The Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) is a computerized assessment of cognitive abilities used for management of sport-concussion that has been translated into 22 languages. Research suggests that language of administration may affect ImPACT performance in bilingual individuals. This study examined the rate of invalid baselines in bilingual/monolingual athletes and in different languages of administrations to explore any potential language biases in ImPACT’s validity index. Methods Participants included 47,677 athletes (Mage = 15.11; 57.37% male) from across Nevada who completed a baseline assessment. There were 90 different languages reported among 10,798 bilingual athletes (22.65%). Chi-square analyses were conducted to examine group differences in rate of invalid baselines by language (monolingual/bilingual) and administration language. Results Overall, 6.2% of athletes produced invalid baselines. There were no significant differences in the rate of invalid baselines in self-reported monolingual (6.1%) and bilingual athletes (6.4%; p > .05). There were 12 different languages of administration; however, due to small sample sizes of some administration languages, further analyses were only conducted with English and Spanish administrations. There were no significant differences in invalid baselines in English (6.2%) and Spanish administrations (7.3%; p > .05). Additionally, among the bilingual Spanish/English speakers, there were no significant differences in invalid baselines in English (6.4%) and Spanish administrations (6.5%; p > .05). Conclusion The current study demonstrates that rates of invalid baselines do not differ based on monolingualism/bilingualism or administration language. This is promising given the high demand for baseline testing, an increase in athletes’ diverse language abilities, and various available languages of ImPACT administration.

scholarly journals Effects of Ayahuasca on Personality: Results of Two Randomized, Placebo-Controlled Trials in Healthy Volunteers

2021 ◽  
Vol 12 ◽  
Author(s):  
Juliana Mendes Rocha ◽  
Giordano Novak Rossi ◽  
Flávia L. Osório ◽  
José Carlos Bouso Saiz ◽  
Gabriela De Oliveira Silveira ◽  
...  
Keyword(s):  
Healthy Volunteers ◽  
Controlled Trial ◽  
Small Sample ◽  
Group Differences ◽  
Clinical Samples ◽  
Controlled Trials ◽  
Parallel Group ◽  
Neo Five Factor Inventory ◽  
Small Sample Sizes ◽  
Induced Changes

Rationale: Previous studies with the serotonergic hallucinogens LSD and psilocybin showed that these drugs induced changes in personality traits, such as increases in Openness. However, results are inconsistent, and the effects of ayahuasca on personality were never investigated in a controlled trial.Objectives: To assess the effects of ayahuasca on personality in two randomized, placebo-controlled trials in healthy volunteers.Methods: Data from two parallel-group, randomized, placebo-controlled trials in healthy volunteers were included. In the first trial, 15 volunteers ingested ayahuasca or placebo, while in the second trial 15 volunteers received placebo+ayahuasca or cannabidiol (CBD)+ayahuasca. Personality was assessed with the NEO-Five Factor Inventory (NEO-FFI) at baseline and 21 days post-treatment.Results: There were significant differences between groups in baseline Openness scores, but not on day 21. A significant increase in Openness scores was observed in the placebo + ayahuasca group in study 2. No other within-group differences were observed for any other domain.Conclusions: Ayahuasca produced inconsistent effects on personality since it induced significant increase in Openness 21 days post-drug intake only in one of the trials. The absence of significant differences in the other ayahuasca groups could be due to small sample sizes and baseline differences among groups. The effects of ayahuasca and other serotonergic hallucinogens on personality should be further investigated in clinical samples.

scholarly journals A-024 The Relationship Between Levels of Insight and Memory Performance in Patients with Dementia

2020 ◽  
Vol 35 (6) ◽  
pp. 814-814
Author(s):  
Cohen C ◽  
Guidotti Breting L ◽  
Klipfel K ◽  
Geary E ◽  
Sweet J
Keyword(s):  
Test Performance ◽  
Memory Performance ◽  
Verbal Learning ◽  
Self Report ◽  
Group Differences ◽  
Or Education ◽  
Cognitive Changes ◽  
Significant Group ◽  
Post Hoc ◽  
The Relationship

Abstract Objective Impaired awareness of cognitive and functional decline is common in dementia syndromes. Insight into cognitive changes is often assessed during a clinical interview, questioning of independent activities of daily living, or via self-report measures of functional abilities. Few studies have examined patient insight in a neuropsychological test performance. The current study investigated the relationship between memory performance on the Wechsler Memory Scale Fourth Edition(WMS-IV) and the Hopkins Verbal Learning Test-Revised(HVLT-R) with level of insight in patients with dementia. Insight was determined from the clinician-based insight rating item on the Behavioral Dyscontrol Scale-II(BDS-II). Method Patients with dementia (ages 50–91) from an outpatient clinic referred for memory testing were divided into groups based on their BDS-II insight score: intact(n = 52), moderate(n = 30), and none/poor(n = 29). One-way ANOVA and post hoc analyses examined the insight differences for immediate recall(IR) and delayed recall(DR) trials on the WMS-IV Visual Reproduction(VRI/II) and Logical Memory(LMI/II) subtests and the HVLT-R. No group differences were found for age or education. Results Analyses revealed significant group differences on the HVLT-R IR [F(2,96) = 5.33,p < .01] and VRI [F(2,100) = 4.88,p < .01], with no significant differences for LM. Post hoc analyses demonstrated poorer performance in the none/poor insight group compared to the moderate (HVLT:p < .05,Cohen’s(d) = .95;VR:p < .05,d = .67) and intact insight groups (HVLT:p < .05,d = .75;VR:p < .05,d = .71). Performance between moderate and intact groups did not differ. There were no significant group effects in the three DR measures. Conclusions Findings suggest that patients with poor insight performed worse on IR measures. The presence of poor insight, in the context of impaired IR performances, may assist in recommendations regarding future functional supports.

Patients with Right Frontal Lesions are Unable to Assess and Use Advice to Make Predictive Judgments

2004 ◽  
Vol 16 (1) ◽  
pp. 74-89 ◽  
Author(s):  
Marian Gomez-Beldarrain ◽  
Clare Harries ◽  
Juan Carlos Garcia-Monco ◽  
Emma Ballus ◽  
Jordan Grafman
Keyword(s):  
Decision Making ◽  
Frontal Lobe ◽  
Parietal Lobe ◽  
Memory Performance ◽  
Group Differences ◽  
Frontal Lobe Lesions ◽  
Economic Decision Making ◽  
Patient Groups ◽  
Frontal Lesions ◽  
Frontal Lobe Lesion

Frontal lobe damage impairs decision-making. Most studies have employed gambling and probabilistic tasks, which have an emotional (reward-punishment) component and found that patients with ventromedial sector lesions have exceptional difficulty performing normally on these tasks. We have recently presented an economic decision-making task to patients and normal volunteers that required them to not only forecast an economic outcome but also to weigh advice from four advisors about the possible outcome across 40 trials. We studied 20 patients with right frontal lobe lesions and 9 patients with parietal lobe lesions and compared their performance to 20 matched controls. Frontal lobe lesion patients were inconsistent at using advice and their forecasts were poor. Patients with dorsolateral but not orbito-frontal lesions showed some ability to assess advice. Patients with parietal lobe lesions were good at assessing advice but were slow at doing so; they were consistent but poor at using advice and their use of advice was unrelated to their forecasting. All three patient groups were overconfident in their own performance. In contrast, controls could both use and assess advice, their ability to use advice was mediated by their ability to assess it, and they were not overconfident. Group differences on an overall measure of accuracy on this task were associated with an ability to accurately plan. Differences in ability to assess and forecast were associated with planning and working memory performance. These findings indicate that patients with both right dorsolateral and orbito-frontal lesions may be impaired when required to make complex decisions related to forecasting and judgment. Our findings enlarge the scope of decision-making deficits seen in patients with frontal lobe lesions and indicate additional circumstances in which patients with frontal lobe lesions will have difficulty in deciding.

scholarly journals Stimulus Onset Hub: An open-source, low latency, and opto-isolated trigger box for neuroscientific research replicability and beyond

2019 ◽  
Author(s):  
Charles E. Davis ◽  
Jacob G. Martin ◽  
Simon J. Thorpe
Keyword(s):  
Open Source ◽  
Low Cost ◽  
Eye Gaze ◽  
Stimulus Onset ◽  
Small Sample ◽  
Manual Response ◽  
Replication Crisis ◽  
Stimulus Timing ◽  
Small Sample Sizes ◽  
Almost All

There is currently a replication crisis in many fields of neuroscience and psychology, with some estimates claiming up to 64% of research in psychological science is not reproducible. Three common culprits which have been suspected to cause the failure to replicate such studies are small sample sizes, “hypothesizing after the results are known,” and “p-hacking.” Here, we introduce accurate stimulus timing as an additional possibility. Accurate stimulus onset timing is critical to almost all psychophysical research. Auditory, visual, or manual response time stimulus onsets are typically sent through wires to various machines that record data such as: eye gaze positions, electroencephalography, stereo electroencephalography, and electrocorticography. These stimulus onsets are collated and analyzed according to experimental condition. If there is variability in the temporal accuracy of the delivery of these onsets to external systems, the quality of the resulting data and scientific analyses will degrade. Here, we describe an approximately $200 Arduino based system and associated open-source codebase which achieved a 5.34 microsecond delay from the inputs to the outputs while electrically opto-isolating the connected external systems. Using an oscilloscope, the device is configurable for different environmental conditions particular to each laboratory (e.g. light sensor type, screen type, speaker type, stimulus type, temperature, etc). This low-cost open-source project delivered electrically isolated stimulus onset Transistor-Transistor Logic triggers with a median precision of 5.34 microseconds and was successfully tested with 7 different external systems that record eye and neurological data.

Comparison of Auditory, Language, Memory, and Attention Abilities in Children With and Without Listening Difficulties

2020 ◽  
Vol 29 (4) ◽  
pp. 710-727
Author(s):  
Beula M. Magimairaj ◽  
Naveen K. Nagaraj ◽  
Alexander V. Sergeev ◽  
Natalie J. Benafield
Keyword(s):  
Auditory Processing ◽  
Short Term Memory ◽  
Group Differences ◽  
Long Term Memory ◽  
Short Term ◽  
Significant Group ◽  
Term Memory ◽  
Memory And Attention ◽  
Speed And Accuracy

Objectives School-age children with and without parent-reported listening difficulties (LiD) were compared on auditory processing, language, memory, and attention abilities. The objective was to extend what is known so far in the literature about children with LiD by using multiple measures and selective novel measures across the above areas. Design Twenty-six children who were reported by their parents as having LiD and 26 age-matched typically developing children completed clinical tests of auditory processing and multiple measures of language, attention, and memory. All children had normal-range pure-tone hearing thresholds bilaterally. Group differences were examined. Results In addition to significantly poorer speech-perception-in-noise scores, children with LiD had reduced speed and accuracy of word retrieval from long-term memory, poorer short-term memory, sentence recall, and inferencing ability. Statistically significant group differences were of moderate effect size; however, standard test scores of children with LiD were not clinically poor. No statistically significant group differences were observed in attention, working memory capacity, vocabulary, and nonverbal IQ. Conclusions Mild signal-to-noise ratio loss, as reflected by the group mean of children with LiD, supported the children's functional listening problems. In addition, children's relative weakness in select areas of language performance, short-term memory, and long-term memory lexical retrieval speed and accuracy added to previous research on evidence-based areas that need to be evaluated in children with LiD who almost always have heterogenous profiles. Importantly, the functional difficulties faced by children with LiD in relation to their test results indicated, to some extent, that commonly used assessments may not be adequately capturing the children's listening challenges. Supplemental Material https://doi.org/10.23641/asha.12808607

Behavioral and emotional differences between children of divorce and children from intact families: Clinical significance and mediating processes *This study is part of a dissertation () supported from the German research community.

2002 ◽  
Vol 61 (1) ◽  
pp. 5-14 ◽  
Author(s):  
Andreas Schick
Keyword(s):  
Self Esteem ◽  
Research Community ◽  
Children Of Divorce ◽  
Group Differences ◽  
Significant Group ◽  
Intact Families ◽  
Divorce Adjustment ◽  
Theoretical Assumptions ◽  
German Research ◽  
Clinically Significant

The following study is based on a sample of 241 9-13-year-old children (66 children from divorced parents, 175 children from non divorced parents). They were examined for differences regarding anxiety, self-esteem, different areas of competence, and degree of behavior problems. With a focus on the children’s experiences, the clinically significant differences were examined. Clinically significant differences, revealing more negative outcomes for the children of divorce, were only found for social anxiety and unstable performance. The frequency of clinical significant differences was independent of the length of time the parents had been separated. The perceived destructiveness of conflict between the parents one of four facets of interparental conflict in this study functioned as a central mediator of the statistically significant group differences. The children’s perception of the father’s social support was a less reliable indicator of variance. Further studies should try to make underlying theoretical assumptions about the effects of divorce more explicit, to distinguish clearly between mediating variables, and to investigate them with respect to specific divorce adjustment indicators.

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