A Psychophysical Measure of Visual and Kinaesthetic Spatial Discriminative Abilities of Adults and Children

Perception ◽  
1986 ◽  
Vol 15 (3) ◽  
pp. 313-324 ◽  
Author(s):  
Victor J Manyam
Keyword(s):  
Age Groups ◽  
Psychophysical Method ◽  
Visual Responses ◽  
Variable Stimulus ◽  
Experimental Conditions ◽  
Adult Performance ◽  
Quantitative Estimates ◽  
Adults And Children ◽  
Simultaneous Comparisons ◽  
Method Of Adjustment

Quantitative estimates of the spatial discriminative capacities of the visual and kinaesthetic systems in adults and children were obtained. Intersensory integration was investigated by including spatial discriminations based on congruent visual plus kinaesthetic reafference. The psychophysical method of adjustment was used with simultaneous comparisons of a fixed and a variable stimulus. The subject's task was to estimate when the variable stimulus (ellipse) was identical to the standard one (circle), under one of three modality conditions: vision, kinaesthesis, and vision plus kinaesthesis. After a pilot study with adults, children (aged 8, 10, and 12 years) and adults were both tested. Subjects from each age group were randomly allocated to each of the three experimental conditions. Results show that the visual and kinaesthetic estimates of the 8- and 10-year-old subjects did not differ significantly, but the visual responses of the adults and 12 year olds were significantly more accurate than corresponding kinaesthetic estimates. Bisensory estimates were significantly more accurate than visual responses only for the 8- and 10-year-old age groups. Intramodal comparisons showed the kinaesthetic estimates of the 8, 10, and 12 year olds to be significantly more accurate than the corresponding adult performance. Adult visual estimates were significantly more accurate than those made by 8 year olds, but were not significantly different from the visual responses of 10 and 12 year olds. Estimates based on bisensory reafference did not differ from each other across the four age groups. It is concluded that modality adeptness and dominance are task dependent and empirically determined rather than being innate properties of sensory systems. The data indicate that intersensory differentiation rather than integration occurs with maturity.

The Effect of Psychophysical Method on the Loudness of Continuous and Interrupted Pure Tones

1979 ◽  
Vol 22 (4) ◽  
pp. 717-730
Author(s):  
Dennis Hampton ◽  
Ira M. Ventry
Keyword(s):  
Psychophysical Method ◽  
Experimental Conditions ◽  
Mean Values ◽  
Tracking Method ◽  
Tracking Tasks ◽  
Loudness Judgment ◽  
Pure Tones ◽  
Comfortable Loudness ◽  
Method Of Adjustment ◽  
Method Of Constant Stimuli

Using the Bekesy tracking method for loudness judgment tasks such as most comfortable loudness (MCL) and recalled loudness (RL) measurements, normal listeners have tracked continuous (C) tones at lesser intensities than interrupted (I) tones. The resulting continuous/interrupted (C/I) separations have ranged up to 22 dB. Explanations of the unexpected C/I separations have not been in agreement. The purpose of this study was to investigate whether psychophysical method has a significant effect on the C/I separation. Subjects were six normal-hearing adults, each of whom participated in three practice and ten test sessions of one hour each. Thirty-six experimental conditions were presented. The test signals were C tones, 200/200 msec I tones and 200/800 msec I tones, all at 1 kHz. The reference intensities were 20, 50 and 80 dB SPL. The four methods were Bekesy tracking method (BTM), method of adjustment (MAdj), method of limits (ML) and method of constant stimuli difference (MCSD). Mean values for Point of Subjective Equality and C/I separation were calculated. C/I separations obtained with the BTM were significantly larger than C/I separations obtained with any other psychophysical method. These results demonstrate that C/I separations obtained during suprathreshold Bekesy tracking tasks by normal hearers are largely caused by the measurement method itself rather than by differences in C and I tone loudness. Time order errors could explain the BTM effect.

scholarly journals Clinical features and outcome of Covid-19 in individuals without Comorbidities. Do children have the advantage?

2021 ◽  
Vol 8 (2) ◽  
pp. 88-93
Author(s):  
Dr. Abhishek Kumar ◽  
◽  
Dr. Nilu Kumari ◽  
Dr. Ranjeet Kumar Singh ◽  
Dr. Alok Kumar ◽  
...  
Keyword(s):  
Severe Disease ◽  
Age Groups ◽  
Asymptomatic Infection ◽  
Healthy Individuals ◽  
Adult Group ◽  
Middle Aged ◽  
History Of ◽  
Adults And Children ◽  
The Mean ◽  
Respiratory Complaints

Objective: Information regarding clinical characteristics and the natural course of COVID-19amongst individuals without comorbidities is scarce. We therefore conducted a retrospectiveobservational study to decipher the disease profile in two different age groups, middle-aged (40-59years) and children (up to 12 years). Method: Study was conducted by reviewing the medicalrecords of all patients in the desired age groups and excluding all those with preexisting illness(called comorbidities). Result: A total of 154 and 27 patients were enrolled and studied in themiddle-aged adults and children group respectively. Males dominated in both groups with a sex ratioof 2.9 in adults and 1.7 in children. Most of the children (92.5%) had a history of exposure from aninfected family member, while in the adult group history of contact was present in 71.4% ofpatients.62.9% of children had an asymptomatic infection which was significantly higher than 22.8%in adults. Cough and fever were the most common symptoms in both age groups, but adults weremore likely to have respiratory complaints when compared with children.11 (7.1%) patients in theadult group had severe disease while in the children group none had severe disease. Similarly in theadult group 11 patients required ICU admission, but none in the children group. The mean durationof RTPCR positivity was similar in both groups. There was 1 (0.6%) expiry in the adult groupwhereas none in children. Conclusion: Healthy individuals in both middle-aged and children grouptend to have milder disease and both harbour the virus for the almost same duration but adults aremore symptomatic in comparison to children and hence children are more likely to be potentialasymptomatic carrier and transmitter of infection.

Interleukin-2 Transiently Inhibits Pulsatile Growth Hormone Secretion in Young but not Older Healthy Men

2021 ◽  
Author(s):  
Ferdinand Roelfsema ◽  
Rebecca Yang ◽  
Johannes D Veldhuis
Keyword(s):  
Hormone Secretion ◽  
Interleukin 2 ◽  
Age Groups ◽  
Growth Hormone Secretion ◽  
Experimental Conditions ◽  
Deconvolution Analysis ◽  
Healthy Men ◽  
Gh Secretion ◽  
Older Subjects ◽  
Young Subjects

Abstract Context Interleukin-2 (IL2), a proinflammatory cytokine, has been used to treat malignancies. Increased cortisol and ACTH were noted, but GH secretion was not investigated in detail. Objective We quantified GH secretion after a single sc injection of IL2 in 17 young and 18 older healthy men in relation to dose, age and body composition. Design This was a placebo-controlled, blinded, prospectively randomized cross-over study. At 20:00 h IL2 (3 or 6 million units per m2 ) or saline was injected sc. Lights were off between 23:00 and 07:00 h. Blood was sampled at 10-min intervals for 24 h. Outcome measures Deconvolution analysis of GH secretion. Results GH profiles were pulsatile under both experimental conditions and lower in older than young volunteers. Since the effect of IL2 might be time-limited, GH analyses were performed on the complete 24-h series and the 6 h after IL2 administration. Total and pulsatile 24-h GH secretion decreased nonsignificantly. Pulsatile secretion fell over the first 6 h after IL2 (P=0.034), with visceral fat as covariate (P=0.003), but not age(P=0.10). Plots of cumulative 2-h bins of GH pulse mass showed a distinction by treatment and age groups: a temporary GH decrease of 32% and 28% occurred in the first 2-h bins after midnight (P=0.019 and 0.038) in young subjects, while in older subjects no differences were present at any time point. Conclusion This study demonstrates that IL2 temporarily diminishes GH secretion in young, but not elderly, men.

Regulation of expiratory muscles during postnatal development in anesthetized piglets

1993 ◽  
Vol 74 (6) ◽  
pp. 2655-2660 ◽  
Author(s):  
I. Litmanovitz ◽  
R. J. Martin ◽  
M. A. Haxhiu ◽  
L. Cattarossi ◽  
B. Haxhiu-Poskurica ◽  
...  
Keyword(s):  
Postnatal Development ◽  
Age Groups ◽  
Respiratory Control ◽  
Transversus Abdominis ◽  
Vagal Afferents ◽  
Postnatal Life ◽  
Experimental Conditions ◽  
Rib Cage ◽  
Before And After ◽  
Expiratory Muscles

We compared maturation of the responses of the rib cage [triangularis sterni (TS)] and abdominal [transversus abdominis (TA)] expiratory muscles with each other and with the responses of the diaphragm (DIA) during hypercarbic and hypoxic stimulation. Studies were performed in anesthetized (urethan and chloralose) piglets of two age groups (< 6 days, n = 10; 14–21 days, n = 11) before and after bilateral cervical vagotomy. Hypercarbia (7% CO2–93% O2) was associated with comparable sustained increases in the minute electromyograms (EMGs) of both TS and TA, which were closely coupled to the DIA responses in both age groups. Hypoxia (12% O2–88% N2) caused a biphasic response of the minute EMG of both expiratory muscles and DIA; these biphasic responses were less prominent at 14-21 days than at < 6 days. Vagotomy caused an increase in the amplitude of both TS and TA (38 +/- 30 and 27 +/- 21%, respectively) as well as the DIA (45 +/- 16%) but did not affect their relative responses to chemostimulation. We conclude that during postnatal development 1) the rib cage and abdominal expiratory muscle responses to chemostimulation are coupled to each other and parallel those of the DIA and 2) the presence of vagal afferents attenuates the drive to both inspiratory and expiratory motoneurons under the current experimental conditions but does not influence the relative responses of expiratory muscles and DIA to hypercarbia or hypoxia. We speculate that comparable activation of inspiratory and expiratory pumping muscles serves to stabilize respiratory control in the face of altered chemosensory or vagal inputs during early postnatal life.

Executive Control on Memory Test Performance across Life: Test of Memory Strategies

2019 ◽  
Vol 22 ◽  
Author(s):  
María Abellán-Martínez ◽  
Miguel Ángel Castellanos López ◽  
María Luisa Delgado-Losada ◽  
Raquel Yubero ◽  
Nuria Paúl ◽  
...  
Keyword(s):  
Episodic Memory ◽  
Executive Functions ◽  
Test Performance ◽  
Initial Conditions ◽  
Cognitive Strategies ◽  
Age Groups ◽  
Memory Test ◽  
Experimental Conditions ◽  
Memory Tests ◽  
Memory Strategies

Abstract The ability to generate memory strategies is a key factor in performance of episodic memory tests. There is evidence about the inefficient use of memory strategies in old adults. However, a question remains unresolved: Worse performance on memory test in the older people is due to an inability to mobilize cognitive strategies or to an episodic memory deficit? In this study we tried to answer it by using the Test of Memory Strategies (TMS), which parametrically reduces the need of executive functions on memory tests. The test consists of five experimental conditions (TMS1–5) where a progressive external organization of the material reduces the need to mobilize memory strategies. TMS was applied to a sample of 180 participants (n = 180) divided into three age groups (25–45; 46–65; 66–85). The results showed an increased performance in all groups groups (F(2, 177) = 14.79, p < .001) across conditions (F(3.88,674.04) = 292.48, p < .001), without group differences in those conditions with a maximum reduction of the need of executive functions (F(7.61,674.04) = 1.95, p = .053). However, middle age and older adults showed more difficulties in establishing cognitive strategies, in the initial conditions. These results lead to the conclusion that the typical pattern of low performance on episodic memory tasks in the older population may be due to the deterioration of executive functions and not mainly to a primary decline of memory process.

scholarly journals Cardiac baroreflex hysteresis is one of the determinants of the heart period variability asymmetry

2019 ◽  
Vol 317 (4) ◽  
pp. R539-R551 ◽  
Author(s):  
Beatrice De Maria ◽  
Vlasta Bari ◽  
Beatrice Cairo ◽  
Emanuele Vaini ◽  
Raphael Martins de Abreu ◽  
...  
Keyword(s):  
Healthy Subjects ◽  
Age Groups ◽  
Positive Association ◽  
Heart Period ◽  
Experimental Conditions ◽  
Significant Positive Association ◽  
Asymmetric Behavior ◽  
Sequence Method ◽  
The Difference ◽  
Spontaneous Fluctuations

In heart period (HP) variability (HPV) recordings the percentage of negative HP variations tends to be greater than that of positive ones and this pattern is referred to as HPV asymmetry (HPVA). HPVA has been studied in several experimental conditions in healthy and pathological populations, but its origin is unclear. The baroreflex (BR) exhibits an asymmetric behavior as well given that it reacts more importantly to positive than negative arterial pressure (AP) variations. We tested the hypothesis that the BR asymmetry (BRA) is a HPVA determinant over spontaneous fluctuations of HP and systolic AP (SAP). We studied 100 healthy subjects (age from 21 to 70 yr, 54 men) comprising 20 subjects in each age decade. Electrocardiogram and noninvasive AP were recorded for 15 min at rest in supine position (REST) and during active standing (STAND). The HPVA was evaluated via Porta’s index and Guzik’s index, while the BRA was assessed as the difference, and normalized difference, between BR sensitivities computed over positive and negative SAP variations via the sequence method applied to HP and SAP variability. HPVA significantly increased during STAND and decreased progressively with age. BRA was not significantly detected both at REST and during STAND. However, we found a significant positive association between BRA and HPVA markers during STAND persisting even within the age groups. This study supports the use of HPVA indexes as descriptors of BRA and identified a challenge soliciting the BR response like STAND to maximize the association between HPVA and BRA markers.

scholarly journals Dietary intake and food sources of added sugar in the Australian population

2016 ◽  
Vol 115 (5) ◽  
pp. 868-877 ◽  
Author(s):  
Linggang Lei ◽  
Anna Rangan ◽  
Victoria M. Flood ◽  
Jimmy Chun Yu Louie
Keyword(s):  
Age Groups ◽  
Food Sources ◽  
Food Groups ◽  
Australian Population ◽  
Added Sugar ◽  
Australian Health ◽  
Sweetened Beverages ◽  
Adolescents And Adults ◽  
Study Population ◽  
Adults And Children

AbstractPrevious studies in Australian children/adolescents and adults examining added sugar (AS) intake were based on now out-of-date national surveys. We aimed to examine the AS and free sugar (FS) intakes and the main food sources of AS among Australians, using plausible dietary data collected by a multiple-pass, 24-h recall, from the 2011–12 Australian Health Survey respondents (n 8202). AS and FS intakes were estimated using a previously published method, and as defined by the WHO, respectively. Food groups contributing to the AS intake were described and compared by age group and sex by one-way ANOVA. Linear regression was used to test for trends across age groups. Usual intake of FS (as percentage energy (%EFS)) was computed using a published method and compared with the WHO cut-off of <10 %EFS. The mean AS intake of the participants was 60·3 (sd 52·6) g/d. Sugar-sweetened beverages accounted for the greatest proportion of the AS intake of the Australian population (21·4 (sd 30·1) %), followed by sugar and sweet spreads (16·3 (sd 24·5) %) and cakes, biscuits, pastries and batter-based products (15·7 (sd 24·4) %). More than half of the study population exceeded the WHO’s cut-off for FS, especially children and adolescents. Overall, 80–90 % of the daily AS intake came from high-sugar energy-dense and/or nutrient-poor foods. To conclude, the majority of Australian adults and children exceed the WHO recommendation for FS intake. Efforts to reduce AS intake should focus on energy-dense and/or nutrient-poor foods.

Survival in adult and pediatric patients with medulloblastoma: A 2018 SEER-based analysis.

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. e14529-e14529
Author(s):  
Hanna Moisander-Joyce ◽  
Anoushka Sinha ◽  
Shannon Fernandez-Ledon ◽  
Davon Lee ◽  
Satoki Hatano ◽  
...  
Keyword(s):  
Age Groups ◽  
Large Cell ◽  
Adult Brain ◽  
World Health ◽  
Rank Test ◽  
Seer Database ◽  
Treatment Protocols ◽  
Survival Difference ◽  
Improved Outcomes ◽  
Adults And Children

e14529 Background: Medulloblastoma (MB) is a malignant neuroectodermal tumor accounting for 30% of pediatric and only 1% of adult brain tumors. In previous studies comparing survival in pediatric and adult MB from the National Cancer Institute Surveillance Epidemiology and End Results (SEER) database no difference has been found. However, diagnostic subgroup analyses have been limited. Methods: We examined survival in children (age 0-19) and adults (20-79) coded as MB in the 2018 SEER database (2000-2016). We used Kaplan Meier analysis, log-rank test and Cox proportional hazard ratios (HR) with 95% confidence intervals (CI). MB in SEER-18 is defined as ICD-O-3 histology codes 9470–9474 (n = 1,728). ICD 9473, supratentorial PNET (sPNET, n = 97) is biologically distinct and therefore it was analyzed separately. Results: We found that 5-year survival for MB, excluding sPNET, was similar in children (n = 1,091, 75.3%) and adults (n = 488, 79.1%) (HR = 0.97, CI: 0.79 – 1.17, p = 0.50). Furthermore, subtype analyses showed no survival difference comparing adults and children with desmoplastic nodular MB (n = 222, p = 0.09), large cell MB (n = 73, p = 0.46), or MB NOS (n = 1330, p = 0.10). Yet, children with sPNET had improved 5-year survival (n = 65, 72.3%) compared to adults (n = 29, 51.7%) (HR = 2.0, CI: 1.10 – 3.92; p = 0.02,). These findings indicate that while survival in patients with MB is similar across age groups, children with sPNET have improved outcomes. Conclusions: In summary, 2018 SEER data for MB continue to show no survival difference between adults and children, suggesting adult patients could appropriately be entered on pediatric MB treatment protocols. Further analyses of the 2018 data are ongoing adjusting for sex, race, and treatment (chemotherapy or radiation). For sPNET, the apparent improved outcomes for children merit further detailed investigation and will be re-evaluated using the new 2016 World Health Organization classification.

Diplacusis Associated with Bilateral High Frequency Hearing Loss

1975 ◽  
Vol 18 (1) ◽  
pp. 5-16 ◽  
Author(s):  
Dale O. Robinson ◽  
John H. Gaeth
Keyword(s):  
Hearing Loss ◽  
Hard Of Hearing ◽  
High Frequency ◽  
Traditional Method ◽  
Constant Error ◽  
Normal Hearing ◽  
Psychophysical Method ◽  
High Frequency Hearing Loss ◽  
Standard Tone ◽  
Method Of Adjustment

Seven normal-hearing subjects and seven subjects with mild bilateral high-frequency sensorineural hearing losses were studied to explore the presence of diplacusis. A tracking procedure of psychophysical method of adjustment-limits was used for pitch judgments rather than the traditional method of adjustment. Each subject was presented with a standard 4000-Hz tone for 500 msec and alternately a variable tone for 500 msec. Subjects were instructed to adjust the variable tone upward or downward in pitch to bracket the pitch sensation of the standard tone. Two intra-aural and two interaural listening conditions were studied. A graphic representation of the subjects' adjustments of the variable tone was obtained for each condition. The resulting tracing indicated frequency correlates to the pitch adjustments from which excursion width and constant error were calculated. Some hard-of-hearing subjects and one normal-hearing subject were found to have diplacusis. Subjects with hearing losses exhibited larger excursion widths for intra- and interaural listening conditions. Subjects with hearing losses tended to be less consistent in pitch judgments than normal-hearing subjects. These findings were interpreted to mean that bilaterally symmetrical hearing losses increase the incidence of pitch aberrations.

A Pragmatic Aspect of Language Sampling

1979 ◽  
Vol 10 (2) ◽  
pp. 104-110 ◽  
Author(s):  
William O. Haynes ◽  
Elizabeth Purcell ◽  
Maureen D. Haynes
Keyword(s):  
Age Groups ◽  
Future Research ◽  
Experimental Conditions ◽  
Language Sampling ◽  
Picture Description ◽  
Pragmatic Aspect ◽  
Linguistic Behavior

This investigation studied language sampling with normal four- and six-year-old children in three conditions: (1) conversation; (2) picture description with the experimenter and child looking at the stimuli; and (3) picture description with the experimenter unable to view the stimuli with the child. The results show statistically significant differences in Developmental Sentence Score and MLU between the age groups and among the experimental conditions. They suggest that children of these ages are able to alter their linguistic behavior as a result of the listener’s perspective. Implications for language sampling and future research are discussed.

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