Age-related changes in the mean and covariance structure of fluid and crystallized intelligence in childhood and adolescence

Intelligence ◽  
2015 ◽  
Vol 48 ◽  
pp. 15-29 ◽  
Author(s):  
Ulrich Schroeders ◽  
Stefan Schipolowski ◽  
Oliver Wilhelm
1976 ◽  
Vol 7 (3) ◽  
pp. 237-245 ◽  
Author(s):  
Vivian Clayton ◽  
Willis F. Overton

A study was conducted to examine the role of concrete and formal operations in a young and old population. In addition, the present study explored the relation between operational thought and Cattell's concept of fluid and crystallized intelligence, as well as the role of differential living arrangements in maintaining operational thought. Eighty females from three age groups (18–20 years, 60–70 years and 70–80 years of age) were tested on a series of Piagetian tasks and indices of fluid and crystallized intelligence. The findings supported the notion that age-related performance differences occur in the area of formal operational thought prior to the time they occur in concrete operational thought. Except for the young sample, the operational tasks were found to be unrelated to fluid intelligence at the age levels represented in this study. Living independently as opposed to living in an old age home did not appear to be a significant factor in maintaining operational thought. Discussion focused on the necessity of identifying those factors which influence the developmental course of formal operational thought across the life span.


1993 ◽  
Vol 123 (6) ◽  
pp. 899-905 ◽  
Author(s):  
Jerald C. Nelson ◽  
Susan J. Clark ◽  
Danielle L. Borut ◽  
Ray T. Tomei ◽  
Esther I. Carlton

2021 ◽  
Vol 72 (3) ◽  
pp. 3139
Author(s):  
Y BELKHIRI ◽  
S BENBIA ◽  
A DJAOUT

The aim of the present study was to evaluate age related changes in testicular histomorphometry and spermatogenic activity of bulls during their sexual development. A total of 36 bulls were selected and divided into four groups (n=9 in each) according to their age. Bulls included in Groups I, II, III and IV were 10, 12, 14 and 16 months old respectively. Left testes of bulls were subjected to histomorphometry after slaughter. Statistical analysis revealed that the secondary spermatocytes, round and elongated spermatids increased significantly (P˂0.05) with the age of bulls. Likewise, both sertoli and leydig cell numbers increased significantly (P˂0.05) with the age of bulls. However, the number of spermatogonia and primary spermatocytes did not change (P>0.05) due to age. The mean tubular diameter increased from 200.70±5.45 μm (10 months of age) to 227.30±9.16 μm (16 months of age) and the total volume of seminiferous tubule per testis from 69.63±1.50 % (10 months of age) to 84.64±2.53 % (16 months of age). A positive linear relationship (P<0.05) was found between meiotic index (Y) and the age (X, in month), which was characterized by the equation 0.048X+3.135 and a coefficient of correlation (R) of 0.396. The correlation between age and sertoli cell efficiency was 0.482 with a regression equation Y= 0.141X+7.696. It is concluded that histomorphometric parameters of the bulls’ testes and spermatogenic activity are correlated with the age, so these parameters provide a reliable tool for the assessment of the reproductive state and sperm production capacity of a bull in a breeding program.


2020 ◽  
Vol 15 (2) ◽  
pp. 61-67
Author(s):  
Fatema Johora ◽  
Abu Sadat Mohammad Nurunnabi ◽  
Dilruba Siddiqua ◽  
Hasna Hena ◽  
Shamim Ara

Background: Changes in the size of the kidney are evident in humans, as age progresses. Objective: To see the age-related changes in the morphological dimensions of the kidney in a sample of the Bangladeshi population. Methods: This crosssectional study was done in the Department of Anatomy, Dhaka Medical College, Dhaka, from July 2008 to June 2009, based on a collection of 140 postmortem human kidneys collected from 70 unclaimed dead bodies from the morgue of the same institution. All the samples of kidney were divided into three age groups, including A (10-19 years), B (20-39 years) and C (40-59 years). The length, breadth and thickness of all the kidneys were measured by using a slide calipers and recorded. Data were expressed as mean±SD. For statistical analysis, independent sample t test and one way ANOVA was used. Results: The length of the right and left kidneys found were 8.72±0.25 cm and 9.28±0.12 cm; 9.73±0.35 cm and 10.31±0.41 cm; 9.68±0.21 cm and 10.24±0.06 cm in group A, B and C respectively. The breadth of the right and left kidneys found were 4.32±0.09 cm and 4.22±0.11 cm; 4.74±0.29 cm and 4.55±0.28 cm; 4.61±0.21 cm and 4.44±0.21 cm in group A, B and C respectively. The thickness of the right and left kidneys found were 2.84±0.10 cm and 2.64±0.05 cm; 3.31±0.16 cm and 3.11±0.10 cm; 3.17±0.07 cm and 3.11±0.10 cm in group A, B and C respectively. The mean length of the left kidneys was found significantly greater than that of the right , whereas the mean breadth and the thickness of the right kidneys were found greater than that of the left kidney in all age groups. Moreover, age related changes were significant in all dimensions (length, breadth and thickness) of the kidney when compared between group A & B and A & C. Conclusion: This study results concluded that the length of the left kidney was greater than that of the right, but the breadth and the thickness of the right kidney were greater than that of the left one in all age groups. In addition, age related changes in all dimensions (i.e. length, breadth and thickness) of the kidneys were evident in middle age versus young adult and older adult versus young adult. J Bangladesh Soc Physiol. 2020, December; 15(2): 61-67


2017 ◽  
Vol 181 (17) ◽  
pp. 452-452 ◽  
Author(s):  
Tiziana Liuti ◽  
Richard Reardon ◽  
Paddy M Dixon

Disorders affecting the equine maxillary cheek teeth and paranasal sinuses are relatively common, but limited objective information is available on the dimensions and relationships of these structures in horses of different ages. The aims of this study were to assess age-related changes in the positioning and anatomical relationships of the individual maxillary cheek teeth with the infraorbital canal and maxillary septum and the volumes of the individual sinus compartments. CT and gross examination were performed on 60 normal equine cadaver heads that were aged by their dentition. The intrasinus position of cheek teeth, length of reserve crowns, relationship to the infraorbital canal and measurements of rostral drift and sinus compartment volumes were assessed from CT images. The findings included that Triadan 10 alveoli lay fully or partially in the rostral maxillary sinus (RMS) in 60% of cases. The infraorbital canal lay directly on the medial aspect of the alveolar apex in younger horses. The Triadan 11’sclinical crowns and apices drifted a mean of 2.48 and 2.83 cm more rostral to the orbit, respectively, in the >15 years old vs the <6 years old age group. The mean volumes of sinus compartments ranged from 175 cm3for the caudal maxillary sinus (CMS) to 4 cm3for the ethmoidal sinus (ES). This information should be of value in the diagnosis and treatment of equine dental and sinus disorders and as reference values for further studies.


2017 ◽  
Vol 31 (3) ◽  
pp. 515-530 ◽  
Author(s):  
V. Chiasson ◽  
E. Vera-Estay ◽  
G. Lalonde ◽  
J. J. Dooley ◽  
M. H. Beauchamp

2013 ◽  
Vol 25 (1) ◽  
pp. 7-16 ◽  
Author(s):  
Christopher R. Beam ◽  
Eric Turkheimer

AbstractGene–environment correlation (rGE) exists both within and between families. Between families, accumulating rGE has been used to explain dramatic changes in phenotypic means over time. The Dickens and Flynn model of increases in cognitive ability over generational time, for example, suggests that small changes in phenotype can lead to subsequent reallocation of environmental resources. This process sets up a reciprocal feedback loop between phenotype and environment, producing accumulating rGE that can cause large changes in the mean of ability, even though ability remains highly heritable in cross-sectional data. We report simulations suggesting that similar processes may operate within twin and sibling pairs. Especially in dizygotic twins and siblings, small differences in phenotype can become associated with reallocations of environmental resources within families. We show that phenotype–environment effects can account for age-related increases in rGE, rapid differentiation of siblings raised together, and widely reported increases in the heritability of behavior during childhood and adolescence.


2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Vida Jojić ◽  
Borislav Čabrilo ◽  
Olivera Bjelić-Čabrilo ◽  
Vladimir M. Jovanović ◽  
Ivana Budinski ◽  
...  

Abstract Background Mammalian mandible and cranium are well-established model systems for studying canalization and developmental stability (DS) as two elements of developmental homeostasis. Nematode infections are usually acquired in early life and increase in intensity with age, while canalization and DS of rodent skulls could vary through late postnatal ontogeny. We aimed to estimate magnitudes and describe patterns of mandibular and cranial canalization and DS related to age and parasite intensity (diversity) in adult yellow-necked mice (Apodemus flavicollis). Results We found the absence of age-related changes in the levels of canalization for mandibular and cranial size and DS for mandibular size. However, individual measures of mandibular and cranial shape variance increased, while individual measures of mandibular shape fluctuating asymmetry (FA) decreased with age. We detected mandibular and cranial shape changes during postnatal ontogeny, but revealed no age-related dynamics of their covariance structure among and within individuals. Categories regarding parasitism differed in the level of canalization for cranial size and the level of DS for cranial shape. We observed differences in age-related dynamics of the level of canalization between non-parasitized and parasitized animals, as well as between yellow-necked mice parasitized by different number of nematode species. Likewise, individual measures of mandibular and cranial shape FA decreased with age for the mandible in the less parasitized category and increased for the cranium in the most parasitized category. Conclusions Our age-related results partly agree with previous findings. However, no rodent study so far has explored age-related changes in the magnitude of FA for mandibular size or mandibular and cranial FA covariance structure. This is the first study dealing with the nematode parasitism-related canalization and DS in rodents. We showed that nematode parasitism does not affect mandibular and cranial shape variation and covariance structure among and within individuals. However, parasite intensity (diversity) is related to ontogenetic dynamics of the levels of canalization and DS. Overall, additional studies on animals from natural populations are required before drawing some general conclusions.


2020 ◽  
Vol 4 (1) ◽  
pp. 004-009
Author(s):  
A Bello ◽  
OA Joseph ◽  
JE Onua ◽  
BI Onyeanusib ◽  
MA Umaru ◽  
...  

This study is aimed at investigating the age related changes in postnatal development of red Sokoto goat stomach. In this study, a total of ten red Sokoto goat digestive tract samples were used and they were grouped into five (5) age categories (group A to E). The goat ages were estimated using dentition eruption and wearing. The stomach was identified and separated from the other part of digestive tract. The gross study revealed that the stomach was composed of four (4) segments that named; rumen, reticulum, omasum and abomasum with anatomical demarcations between them. The biometric study of weight, length, width, thickness, and volume was found to be increasing with advancement in postnatal ages with the following valves shows the mean value of weight, length, width, thickness and volume were to be 29 to 58.0 (g), 23.5, to 52.1 (cm), 15.4 to 29.0 (cm), 0.48 to 1.0 (mm) and102 to 432 (cm3) from group A to group E respectively. Based on the above findings it was suggested that more research should be conducted using histological techniques and electron microscopy in order to finalize on the findings.


1995 ◽  
Vol 18 (4) ◽  
pp. 701-711 ◽  
Author(s):  
Anat Scher ◽  
Emanuel Tirosh ◽  
Michael Jaffe ◽  
Lisa Rubin ◽  
Avi Sadeh ◽  
...  

The sleep habits of 661 Israeli children between the ages of 4 months and 4 years were described by their mothers. Twenty-eight per cent reported that their children woke up at least once a week. In the group of regular wakers, the mean number of interrupted nights per week was 4.7, and the mean number of awakenings per night was 2.0. Significant age-related changes in sleep patterns were indicated. The results of this study suggest that sleep and settling patterns in different sociocultural groups are quite similar. These data indicate the existence of an inherent pattern in the maturation of sleep behaviour in the developing child.


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