Median-Split

Zusammenfassung. Theoretischer Hintergrund: Modelle zur Aufrechterhaltung des ADHS-Syndroms postulieren, dass die allgemeine Aufmerksamkeitsleistung und damit auch die Selbstaufmerksamkeit durch Stress vermindert werden kann. Fragestellung: In der Studie wurde geprüft, ob sich dieser Effekt bereits bei Personen aus der gesunden Bevölkerung zeigt, die einen hohen Ausprägungsgrad an ADHS-ähnlicher Symptomatik aufweisen. Methode: 84 Männer mit einem mittleren Alter von 23 Jahren wurden getestet. Die Stressinduktion erfolgte durch mentale Arithmetik aus dem Trier Sozial Stress-Test. Die Aufmerksamkeitsleistung wurde mit dem Frankfurter Aufmerksamkeitsinventar gemessen. Die Gruppierung der Probanden erfolgte durch Median-Split aufgrund der Selbstbeurteilungsskala aus den Homburger ADHS-Skalen für Erwachsene in solche mit hoher bzw. niedriger ADHS-Tendenz. Ergebnisse: Bezüglich der Aufmerksamkeitsleistung zeigte sich der erwartete Interaktionseffekt (Gruppierung × Bedingung) mit schlechterer Leistung nach Stress nur für Personen mit hoher ADHS-Tendenz (p < .002). Schlussfolgerung: Die Ergebnisse deuten auf den Nutzen der Einbeziehung spezifischer stressbezogener Bausteine in Behandlungsprogramme für ADHS-Patienten hin.

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121 Behavioral Attention Relationships Vary Between Demographic Groups Across Sleep Loss and Recovery

SLEEP ◽

10.1093/sleep/zsab072.120 ◽

2021 ◽

Vol 44 (Supplement_2) ◽

pp. A49-A50

Author(s):

Caroline Antler ◽

Erika Yamazaki ◽

Tess Brieva ◽

Courtney Casale ◽

Namni Goel

Keyword(s):

Sleep Deprivation ◽

Repeated Measures ◽

Age Groups ◽

Response Speed ◽

Sleep Loss ◽

Demographic Groups ◽

Time In Bed ◽

Median Split ◽

The Relationship ◽

High Bmi

Abstract Introduction The Psychomotor Vigilance Test (PVT) is a behavioral attention measure widely used to describe sleep loss deficits. Although there are reported differences in PVT performance for various demographic groups, no study has examined the relationship between measures on the 10-minute PVT (PVT10) and the 3-minute PVT (PVT3) within sex, age, and body mass index (BMI) groups throughout a highly controlled sleep deprivation study. Methods Forty-one healthy adults (mean±SD ages, 33.9±8.9y) participated in a 13-night experiment [2 baseline nights (10h-12h time in bed, TIB) followed by 5 sleep restriction (SR1-5) nights (4h TIB), 4 recovery nights (R1-R4; 12h TIB), and 36h total sleep deprivation (TSD)]. A neurobehavioral test battery, including the PVT10 and PVT3 was completed every 2h during wakefulness. Repeated measures correlation (rmcorr) compared PVT10 and PVT3 lapses (reaction time [RT] >355ms [PVT3] and >500ms [PVT10]) and response speed (1/RT) by examining correlations by day (e.g., baseline day 2) and time point (e.g., 1000h-2000h) within sex groups (18 females), within age groups defined by a median split (median=32, range=21-49y), and within BMI groups defined by a median split (median=25, range=17-31). Results PVT10 and PVT3 1/RT was significantly correlated at all study days and time points excluding at baseline for the younger group and at R2 for the higher BMI group. PVT10 and PVT3 lapses showed overall lower correlations across the study relative to 1/RT. Lapses were not significantly correlated at baseline for any group, for males across recovery (R1-R4), for the high BMI group at R2-R4, for the older group at R2-R3, or for the younger group at SR5 or R3. Conclusion Differentiating participants based on age, sex, or BMI revealed important variation in the relationship between PVT10 and PVT3 measures across the study. Surprisingly, lapses were not significantly correlated at baseline for any demographic group or across recovery for males or the high BMI or older group. Thus, PVT10 and PVT3 lapses may be less comparable in certain populations when well-rested. These findings add to a growing literature suggesting demographic factors may be important factors to consider when evaluating the effects of sleep loss. Support (if any) ONR Award N00014-11-1-0361;NIH UL1TR000003;NASA NNX14AN49G and 80NSSC20K0243; NIHR01DK117488

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Change of Direction Deficit in National Team Rugby Union Players: Is There an Influence of Playing Position?

Sports ◽

10.3390/sports7010002 ◽

2018 ◽

Vol 7 (1) ◽

pp. 2 ◽

Cited By ~ 6

Author(s):

Tomás Freitas ◽

Pedro Alcaraz ◽

Chris Bishop ◽

Julio Calleja-González ◽

Ademir Arruda ◽

...

Keyword(s):

Rugby Union ◽

Drop Jump ◽

Repetition Maximum ◽

Change Of Direction ◽

National Team ◽

Standing Long Jump ◽

Long Jump ◽

Median Split ◽

Rugby Players

The aim of this study was to investigate the change of direction (COD) ability and deficits of elite rugby union players, discriminating between position (backs and forwards), and between “faster and slower players”, in multiple COD tasks. Twenty-four male rugby union players from the Brazilian senior National team completed the following assessments: Squat and countermovement jumps; drop jump; standing long jump, horizontal triple jumps; 40-m linear sprint; Pro-agility, L-Drill, and Zig-zag COD tests; and squat 1-repetition maximum. The differences between backs and forwards and between faster and slower performers were examined using magnitude-based inferences. Backs were faster (in both linear and COD speed tests) and jumped higher than forwards. Moreover, they generated an inferior sprint momentum. No differences were found in COD deficit between playing positions. However, when dividing the sample by median split, faster players outperformed their slower counterparts in all power–speed variables and presented higher COD deficits. These results suggest that separating rugby players by playing position might not discriminate players with different COD skills and that the median split analysis is more sensitive to identifying these differences. Furthermore, the present data indicate that faster rugby players are less efficient at changing direction and tolerating higher approach velocities in COD maneuvers.

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An Associational Examination of the CaptialCube Effect Context for the MPV over the Linguistic Partitions: Testing Sensitivity & Specificity

Accounting and Finance Research ◽

10.5430/afr.v6n2p1 ◽

2017 ◽

Vol 6 (2) ◽

pp. 1

Author(s):

Edward J. Lusk ◽

Michael Halperin

Keyword(s):

A Priori ◽

Market Performance ◽

Random Processes ◽

Random Selection ◽

Testing Model ◽

Performance Variables ◽

Market Effects ◽

Median Split ◽

Sensitivity Specificity ◽

Testing Protocols

In this third examination of the CapitalCubeÔ Market Navigation Platform [CCMNP] we have selected the previously vetted set of embedded variables: Market Performance Variables [MPV] for their Linguistic Qualifiers [LQ] considering their directional market effects or MPV[LQ[{Neutral: Unfavorable: Favorable}]]. In the testing, we are interested in the Sensitivity and the Specificity of these vetted variables over the annual S&P500 Panel from 2005 to 2013. The inference framework employed a Median Split: High or Low for each of the 13 MPV tested and a random selection to avoid the FPE-jeopardy that is part of the Chi2 testing model. We used the Tamhane & Dunlop cut-off to identify Chi2 cells effects of interest and used these to develop the Sensitivity and the Specificity tests. Results: We were able to reject the a priori Nulls proffered for the testing protocols indicating that one may reject the supposition that the labeling of the LQ is formed by random processes in the CCMNP.

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Slower adaptation of control strategies in individuals with high impulsive tendencies

Scientific Reports ◽

10.1038/s41598-021-99764-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Fanny Grisetto ◽

Yvonne N. Delevoye-Turrell ◽

Clémence Roger

Keyword(s):

Control Strategies ◽

Task Demands ◽

Proactive Control ◽

Reactive Control ◽

Score Distribution ◽

Individual Level ◽

Control Processes ◽

Split Method ◽

Median Split ◽

Reactive Processes

AbstractFlexible use of reactive and proactive control according to environmental demands is the key to adaptive behavior. In this study, forty-eight adults performed ten blocks of an AX-CPT task to reveal the strength of proactive control by the calculation of the proactive behavioral index (PBI). They also filled out the UPPS questionnaire to assess their impulsiveness. The median-split method based on the global UPPS score distribution was used to categorize participants as having high (HI) or low (LI) impulsiveness traits. The analyses revealed that the PBI was negatively correlated with the UPPS scores, suggesting that the higher is the impulsiveness, the weaker the dominance of proactive control processes. We showed, at an individual level, that the PBI increased across blocks and suggested that this effect was due to a smaller decrease in reactive control processes. Notably, the PBI increase was slower in the HI group than in the LI group. Moreover, participants who did not adapt to task demands were all characterized as high impulsive. Overall, the current study demonstrates that (1) impulsiveness is associated with less dominant proactive control due to (2) slower adaptation to task demands (3) driven by a stronger reliance on reactive processes. These findings are discussed in regards to pathological populations.

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Comparison of Selected Methods of Transformations of Proportions

Perceptual and Motor Skills ◽

10.2466/pms.1983.57.2.423 ◽

1983 ◽

Vol 57 (2) ◽

pp. 423-426 ◽

Cited By ~ 1

Author(s):

Joseph C. Bledsoe

Keyword(s):

Sex Role ◽

White Teachers ◽

Error Variance ◽

Logit Analysis ◽

Heterogeneity Of Variance ◽

Median Split ◽

Two Indices

44 female white teachers were observed for six separate 20-min. periods for a total of 88 hr. The frequency of approving and disapproving behaviors toward boys and girls were obtained and two indices consisting of proportions of approving to total behaviors of boys and girls were derived. After observation, the Bern Sex-role Inventory was administered to the teachers, and four groups of 11 teachers each were classified by a median-split procedure as androgynous, masculine, feminine, and undifferentiated. The two proportions were then transformed to arc sine (angit), probit, and logit scales and compared to the results of the analysis of the nontransformed proportions. Differences in all analyses showed girls were more favorably perceived than boys; feminine teachers showed greatest differences and masculine teachers showed the smallest differences. All differences between approving behaviors of boys and girls were significant except for those of masculine teachers. The three transformations gave essentially similar results with approximately 4% greater non-error variance. The transformations eliminated a gross heterogeneity of variance in the proportions and the logit analysis was most sensitive to differences among types of teacher and pupil-sex groups. Implications were briefly discussed.

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055 Novel sleep-dependent spatial memory and navigation task using Minecraft

SLEEP ◽

10.1093/sleep/zsab072.054 ◽

2021 ◽

Vol 44 (Supplement_2) ◽

pp. A23-A23

Author(s):

Katharine Simon ◽

Gregory Clemenson ◽

Brandon Clayton ◽

Jing Zhang ◽

Elisabet Alzueta ◽

...

Keyword(s):

Spatial Memory ◽

Test Performance ◽

Target Location ◽

Spatial Navigation ◽

Memory Task ◽

Spatial Location ◽

Delay Test ◽

Location Accuracy ◽

Median Split ◽

Dependent Learning

Abstract Introduction Spatial navigation and memory are hippocampally-dependent and decrease with age, yet, ecologically-valid methods remain elusive. We developed an engaging and inherently flexible spatial navigation/memory task using the Minecraft platform to test sleep-dependent memory. We validated baseline performance and learning rates across two separate Minecraft environments. Methods Using a within-subjects design, twenty-two subjects experienced two conditions (wake/sleep) and two Minecraft environments, counterbalanced across subjects. At encoding, subjects learned the locations of 12 objects. Memory for object location accuracy and navigation route (distance between start and target; vector: angle of direction towards target location from start) was tested immediately and following 12-hours of wake or sleep. Post-hoc analyses were conducted using a median split on subjects’ Immediate test performance. Results There were no significant differences across conditions for the Immediate test performance (t(22) = .567, p = .576) across the two environments. Delayed test showed greater improvement in accuracy after sleep compared to wake (t(18) = 2.795, p=.012), no differences in distance or vector. Median split by Immediate test performance revealed that initially lower performance showed the greatest improvement after delay in the sleep group (t(18) = 2.818, p =.011), but not the wake group (t(18) = -1.051, p =.308). Additionally, these same subjects’ vector direction was initially worse at Immediate Test (t(18) = -2.9, p = .01), and improved with sleep, becoming equivalent to the better performers at Delay test (t(18) = -.336, p = .74). Conclusion We demonstrate a novel spatial navigation/memory tasks using Minecraft that shows sleep-dependent learning across two distinct environments. We showed enhancement of spatial location accuracy after a night of sleep compared to wake. We further demonstrate that with sleep, those with worse initial performance show the greatest memory and navigation improvement, consistent with other findings that sleep supports enhancement of weaker memories and extended to the spatial-domain. This novel platform can be used to evaluate spatial memory across the lifespan and within special clinical populations. Support (if any) NIH R01 AG061355

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DNA Methylation Signatures of Breastfeeding in Buccal Cells Collected in Mid-Childhood

Nutrients ◽

10.3390/nu11112804 ◽

2019 ◽

Vol 11 (11) ◽

pp. 2804 ◽

Cited By ~ 5

Author(s):

Odintsova ◽

Hagenbeek ◽

Suderman ◽

Caramaschi ◽

van Beijsterveldt ◽

...

Keyword(s):

Dna Methylation ◽

Peripheral Blood ◽

Empirical Studies ◽

Total Sample ◽

Buccal Cells ◽

Maternal Characteristics ◽

Parents And Children ◽

Median Split ◽

Duration Of Breastfeeding ◽

Stratified Analysis

Breastfeeding has long-term benefits for children that may be mediated via the epigenome. This pathway has been hypothesized, but the number of empirical studies in humans is small and mostly done by using peripheral blood as the DNA source. We performed an epigenome-wide association study (EWAS) in buccal cells collected around age nine (mean = 9.5) from 1006 twins recruited by the Netherlands Twin Register (NTR). An age-stratified analysis examined if effects attenuate with age (median split at 10 years; n<10 = 517, mean age = 7.9; n>10 = 489, mean age = 11.2). We performed replication analyses in two independent cohorts from the NTR (buccal cells) and the Avon Longitudinal Study of Parents and Children (ALSPAC) (peripheral blood), and we tested loci previously associated with breastfeeding in epigenetic studies. Genome-wide DNA methylation was assessed with the Illumina Infinium MethylationEPIC BeadChip (Illumina, San Diego, CA, USA) in the NTR and with the HumanMethylation450 Bead Chip in the ALSPAC. The duration of breastfeeding was dichotomized (‘never‘ vs. ‘ever’). In the total sample, no robustly associated epigenome-wide significant CpGs were identified (α = 6.34 × 10–8). In the sub-group of children younger than 10 years, four significant CpGs were associated with breastfeeding after adjusting for child and maternal characteristics. In children older than 10 years, methylation differences at these CpGs were smaller and non-significant. The findings did not replicate in the NTR sample (n = 98; mean age = 7.5 years), and no nearby sites were associated with breastfeeding in the ALSPAC study (n = 938; mean age = 7.4). Of the CpG sites previously reported in the literature, three were associated with breastfeeding in children younger than 10 years, thus showing that these CpGs are associated with breastfeeding in buccal and blood cells. Our study is the first to show that breastfeeding is associated with epigenetic variation in buccal cells in children. Further studies are needed to investigate if methylation differences at these loci are caused by breastfeeding or by other unmeasured confounders, as well as what mechanism drives changes in associations with age.

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The Influence of Food Reinforcement and Eating Disorder Pathology on Weight Change in Adolescents (P21-057-19)

Current Developments in Nutrition ◽

10.1093/cdn/nzz041.p21-057-19 ◽

2019 ◽

Vol 3 (Supplement_1) ◽

Author(s):

Katherine Balantekin ◽

Amanda Crandall ◽

Amanda Ziegler ◽

Jennifer Temple

Keyword(s):

Eating Disorder ◽

Weight Gain ◽

Weight Change ◽

Weight Status ◽

Food Reinforcement ◽

Self Report ◽

Schedules Of Reinforcement ◽

Eating Disorder Examination ◽

Funding Sources ◽

Median Split

Abstract Objectives Both the relative reinforcing value (RRV) of food, or the motivation to obtain food, and eating disorder (ED) pathology have been shown to independently predict weight gain. However, less is known about how the interaction between the RRV of food and ED pathology predicts weight gain over time. Therefore, the purpose of this study was to examine the combined effects of the RRV of food and ED pathology on weight change over 6 months in a sample of adolescents. Methods Participants included 77 12–14 year old adolescents participating in a longitudinal study examining factors that predict changes in weight status. Data presented are from baseline and 6 months. The RRV of food was assessed using a computer task. Participants earned points for energy dense food by pressing a mouse button on a computer across escalating schedules of reinforcement. Participants were classified as “low” or “high” in RRV based on a median split of their total responses. Global ED pathology was assessed at baseline using adolescent self-report on the Eating Disorder Examination Questionnaire. Participants were classified as “low” or “high” in ED pathology based on a median split of their global ED pathology. Four groups were created: low ED pathology/low RRV (n = 20), high ED pathology/low RRV (n = 23), low ED pathology/high RRV (n = 15), and high ED pathology/high RRV (n = 19). Height and weight were measured at both baseline and 6 months and used to calculate zBMI. ANOVA was used to examine differences in zBMI change over 6 months by RRV/ED pathology group. Results zBMI change from baseline to 6 months differed by RRV/ED pathology group (P < .05). Changes in zBMI over 6 months were as follows: - 0.025 ± 0.298 for low ED pathology/low RRV; 0.010 ± 0.322 for high ED pathology/low RRV; - 0.095 ± 0.181 for low ED pathology/high RRV; and 0.186 ± 0.268 for high ED pathology/high RRV. Follow-up contrasts revealed that the high ED pathology/high RRV group experienced greater zBMI changes than the other groups (ps < 0.05). Conclusions While the RRV of food and ED pathology are both independently associated with weight gain, the current study indicates that there may be something unique about the combination of high RRV of food and high ED pathology related to risk of weight gain. Future work is needed to identify strategies to limit weight gain in this vulnerable population. Funding Sources National Institutes of Health.

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Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled Trial

Nutrients ◽

10.3390/nu11102362 ◽

2019 ◽

Vol 11 (10) ◽

pp. 2362 ◽

Cited By ~ 6

Author(s):

Hidese ◽

Ogawa ◽

Ota ◽

Ishida ◽

Yasukawa ◽

...

Keyword(s):

Cognitive Functions ◽

Verbal Fluency ◽

Controlled Trial ◽

Depression Scale ◽

Healthy Adults ◽

Placebo Administration ◽

Double Blind ◽

Randomized Controlled ◽

Median Split ◽

The Mean

This randomized, placebo-controlled, crossover, and double-blind trial aimed to examine the possible effects of four weeks L-theanine administration on stress-related symptoms and cognitive functions in healthy adults. Participants were 30 individuals (nine men and 21 women; age: 48.3 ± 11.9 years) who had no major psychiatric illness. L-theanine (200 mg/day) or placebo tablets were randomly and blindly assigned for four-week administration. For stress-related symptoms, Self-rating Depression Scale, State-Trait Anxiety Inventory-trait, and Pittsburgh Sleep Quality Index (PSQI) scores decreased after L-theanine administration (p = 0.019, 0.006, and 0.013, respectively). The PSQI subscale scores for sleep latency, sleep disturbance, and use of sleep medication reduced after L-theanine administration, compared to the placebo administration (all p < 0.05). For cognitive functions, verbal fluency and executive function scores improved after L-theanine administration (p = 0.001 and 0.031, respectively). Stratified analyses revealed that scores for verbal fluency (p = 0.002), especially letter fluency (p = 0.002), increased after L-theanine administration, compared to the placebo administration, in individuals who were sub-grouped into the lower half by the median split based on the mean pretreatment scores. Our findings suggest that L-theanine has the potential to promote mental health in the general population with stress-related ailments and cognitive impairments.

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