scholarly journals Age-Related Changes in Human and Nonhuman Timing

2017 ◽  
Vol 5 (3-4) ◽  
pp. 261-279 ◽  
Author(s):  
Rannie Xu ◽  
Russell M. Church
Keyword(s):  
Time Perception ◽  
Cognitive Processing ◽  
Cognitive Aging ◽  
Comparative Research ◽  
Biochemical Changes ◽  
Age Related ◽  
Timing Ability ◽  
The Many ◽  
The Brain ◽  
Age Related Changes

The capacity for timed behavior is ubiquitous across the animal kingdom, making time perception an ideal topic of comparative research across human and nonhuman subjects. One of the many consequences of normal aging is a systematic decline in timing ability, often accompanied by a host of behavioral and biochemical changes in the brain. In this review, we describe some of these behavioral and biochemical changes in human and nonhuman subjects. Given the involvement of timing in higher-order cognitive processing, age-related changes in timing ability can act as a marker for cognitive decline in older adults. Finally, we offer a comparison between human and nonhuman timing through the perspective of Alzheimer’s disease. Taken together, we suggest that understanding timing functions and dysfunctions can improve theoretical accounts of cognitive aging and time perception, and the use of nonhuman subjects constitutes an integral part of this process.

Age-related changes in the brain transfer of blood-borne horseradish peroxidase in the hippocampus of senescence-accelerated mouse

1997 ◽  
Vol 93 (3) ◽  
pp. 233-240 ◽  
Author(s):  
M. Ueno ◽  
Ichiro Akiguchi ◽  
Masanori Hosokawa ◽  
Masahiko Shinnou ◽  
Haruhiko Sakamoto ◽  
...  
Keyword(s):  
Horseradish Peroxidase ◽  
Age Related ◽  
The Brain ◽  
Senescence Accelerated Mouse ◽  
Age Related Changes

Exercise Impacts Age-Related Changes in Cognitive Function and Neural Complexity

2016 ◽  
Vol 5 (1) ◽  
pp. 30-38 ◽  
Author(s):  
Jennifer J. Heisz ◽  
Ana Kovacevic
Keyword(s):  
Older Adults ◽  
Cognitive Function ◽  
Executive Functions ◽  
Cognitive Outcomes ◽  
Physically Active ◽  
Age Related ◽  
The Neural Network ◽  
Future Work ◽  
The Brain ◽  
Age Related Changes

Age-related changes in the brain can compromise cognitive function. However, in some cases, the brain is able to functionally reorganize to compensate for some of this loss. The present paper reviews the benefits of exercise on executive functions in older adults and discusses a potential mechanism through which exercise may change the way the brain processes information for better cognitive outcomes. Specifically, older adults who are more physically active demonstrate a shift toward local neural processing that is associated with better executive functions. We discuss the use of neural complexity as a sensitive measure of the neural network plasticity that is enhanced through exercise. We conclude by highlighting the future work needed to improve exercise prescriptions that help older adults maintain their cognitive and physical functions for longer into their lifespan.

Relative potencies of testosterone and 5α-dihydrotestosterone on crowing and cloacal gland growth in the Japanese quail (Coturnix coturnix japonica)

1984 ◽  
Vol 100 (1) ◽  
pp. 19-23 ◽  
Author(s):  
J. Balthazart ◽  
M. Schumacher ◽  
G. Malacarne
Keyword(s):  
Coturnix Japonica ◽  
Coturnix Coturnix Japonica ◽  
Coturnix Coturnix ◽  
Behavioural Activity ◽  
Age Related ◽  
Female Quail ◽  
The Brain ◽  
Relative Potencies ◽  
Cloacal Gland ◽  
Age Related Changes

ABSTRACT It has been suggested that testosterone is less effective at inducing crowing behaviour in young birds than in adults because of the presence of higher levels of steroid 5β-reductase in the young brain, which converts testosterone to inactive 5β-reduced metabolites. This hypothesis was tested indirectly by comparing the relative potencies of 5α-dihydrotestosterone (5α-DHT), which cannot be converted to 5β-metabolities, and testosterone at inducing crowing in young gonadectomized male and female quail. The promotion of cloacal gland growth by these treatments was also assessed since there are no age-related changes in 5β-reductase in this organ. Silicone elastomer implants (2·5, 5 and 10 mm) containing 5α-DHT were more effective at stimulating crowing than similar implants of testosterone whilst there was little difference in their potency at inducing cloacal gland growth. These results are consistent with the hypothesis that brain steroid 5β-reductase regulates the behavioural activity of testosterone in the brain of young birds. J. Endocr. (1984) 100, 19–23

Age-related changes in transmitter glutamate and NMDA receptor/channels in the brain of senescence-accelerated mouse

1992 ◽  
Vol 137 (2) ◽  
pp. 169-172 ◽  
Author(s):  
Yoshihisa Kitamura ◽  
Xue-Hui Zhao ◽  
Toshio Ohnuki ◽  
Makiko Takei ◽  
Yasuyuki Nomura
Keyword(s):  
Nmda Receptor ◽  
Age Related ◽  
The Brain ◽  
Senescence Accelerated Mouse ◽  
Transmitter Glutamate ◽  
Age Related Changes

Nothobranchius fish: an untapped resource for studying aging-related neurodegeneration

2021 ◽  
Vol 14 ◽  
Author(s):  
Tyrone Genade
Keyword(s):  
Behavioral Changes ◽  
Research Focus ◽  
Short Lifespan ◽  
Open Questions ◽  
Age Related ◽  
New Models ◽  
The Brain ◽  
Existing Data ◽  
Untapped Resource ◽  
Age Related Changes

: New models in which aging-related neurodegeneration more closely resembling the combination of pathologies that develop in aging humans are needed. The fish Nothobranchius, which naturally develops such pathologies over the course of its short lifespan, is one such model. This review compares the lifespans and pathologies of different Nothobranchius strains to those of current vertebrate models of aging. Furthermore, existing data pertaining to neurodegeneration in these fish is discussed in the context of their reported neuropathologies, along with open questions related to mammalian chronopathologies. Specifically, the evidence for a Parkinson’s disease-like pathology is discussed. Neurogenesis and age-related changes therein are discussed in the context of siRNA and neurodegeneration. We also discuss changes in the expression of neuropeptide Y in relation to the brain-gut axis and how these change with age. Agerelated behavioral changes are discussed, along with the assays used in their evaluation. Genetic discoveries are outlined and discussed with a view on DJ-1/NRF2 signaling in N. furzeri, and on insights gained from comparative genomics and siRNA studies. Finally, research focus areas are highlighted, and a case is made for the utility of these fish in the study of aging-related neurodegeneration, and to screen for environmental risk factors of aging-related neuropathology.

Examining the nervous system of an older patient

2017 ◽  
pp. 865-870
Author(s):  
Henry J. Woodford ◽  
James George
Keyword(s):  
Nervous System ◽  
White Matter Lesions ◽  
Clinical Situation ◽  
Neurological Assessment ◽  
Risk Of Death ◽  
Age Related ◽  
Power Testing ◽  
The Individual ◽  
The Brain ◽  
Age Related Changes

Ageing is associated with changes in the nervous system, especially the accumulation of neurodegenerative and white matter lesions within the brain. Abnormalities are commonly found when examining older people and some of these are associated with functional impairment and a higher risk of death. In order to reliably interpret examination findings it is important to assess cognition, hearing, vision, and speech first. Clarity of instruction is key. Interpretation of findings must take into account common age-related changes. For example, genuine increased tone should be distinguished from paratonia. Power testing should look for asymmetry within the individual, rather than compare to the strength of the examiner. Parkinsonism should be looked for and gait should be observed. Neurological assessment can incorporate a range of cortical abilities and tests of autonomic function, but the extent of these assessments is likely to be determined by the clinical situation and time available.

scholarly journals Age-related positivity effect on behavioural responses of dogs to human vocalisations

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Iris Smit ◽  
Dora Szabo ◽  
Enikő Kubinyi
Keyword(s):  
Emotional Processing ◽  
Positive Emotions ◽  
Attention And Memory ◽  
Positivity Effect ◽  
Behavioural Responses ◽  
Fundamental Frequencies ◽  
Age Related ◽  
Significant Difference ◽  
The Brain ◽  
Age Related Changes

AbstractAge-related changes in the brain can alter how emotions are processed. In humans, valence specific changes in attention and memory were reported with increasing age, i.e. older people are less attentive toward and experience fewer negative emotions, while processing of positive emotions remains intact. Little is yet known about this “positivity effect” in non-human animals. We tested young (n = 21, 1–5 years) and old (n = 19, >10 years) family dogs with positive (laugh), negative (cry), and neutral (hiccup, cough) human vocalisations and investigated age-related differences in their behavioural reactions. Only dogs with intact hearing were analysed and the selected sound samples were balanced regarding mean and fundamental frequencies between valence categories. Compared to young dogs, old individuals reacted slower only to the negative sounds and there was no significant difference in the duration of the reactions between groups. The selective response of the aged dogs to the sound stimuli suggests that the results cannot be explained by general cognitive and/or perceptual decline. and supports the presence of an age-related positivity effect in dogs, too. Similarities in emotional processing between humans and dogs may imply analogous changes in subcortical emotional processing in the canine brain during ageing.

scholarly journals Age-Related Structural and Functional Changes of the Hippocampus and the Relationship with Inhibitory Control

2020 ◽  
Vol 10 (12) ◽  
pp. 1013
Author(s):  
Sien Hu ◽  
Chiang-shan R. Li
Keyword(s):  
Reaction Time ◽  
Cognitive Aging ◽  
Gray Matter Volume ◽  
Stop Signal ◽  
Sequential Effect ◽  
Stop Signal Task ◽  
Functional Changes ◽  
Age Related ◽  
Stop Signal Reaction Time ◽  
Age Related Changes

Aging is associated with structural and functional changes in the hippocampus, and hippocampal dysfunction represents a risk marker of Alzheimer’s disease. Previously, we demonstrated age-related changes in reactive and proactive control in the stop signal task, each quantified by the stop signal reaction time (SSRT) and sequential effect computed as the correlation between the estimated stop signal probability and go trial reaction time. Age was positively correlated with the SSRT, but not with the sequential effect. Here, we explored hippocampal gray matter volume (GMV) and activation to response inhibition and to p(Stop) in healthy adults 18 to 72 years of age. The results showed age-related reduction of right anterior hippocampal activation during stop success vs. go trials, and the hippocampal activities correlated negatively with the SSRT. In contrast, the right posterior hippocampus showed higher age-related responses to p(Stop), but the activities did not correlate with the sequential effect. Further, we observed diminished GMVs of the anterior and posterior hippocampus. However, the GMVs were not related to behavioral performance or regional activities. Together, these findings suggest that hippocampal GMVs and regional activities represent distinct neural markers of cognitive aging, and distinguish the roles of the anterior and posterior hippocampus in age-related changes in cognitive control.

scholarly journals Functional Implications of Changes in the Senescent Brain: A Review

1978 ◽  
Vol 5 (4) ◽  
pp. 417-424 ◽  
Author(s):  
Charles H.M. Beck
Keyword(s):  
Old Age ◽  
Cognitive Processing ◽  
Memory Trace ◽  
Physiological Changes ◽  
Age Related ◽  
Dopaminergic Systems ◽  
Functional Implications ◽  
The Brain

SUMMARY:The morphological, chemical, and physiological changes in the brain accompanying old age are reviewed. The deterioration of the striatal and hypothalamic dopaminergic systems were implicated in the onset of age related Parkinsonian-like slowing of performance and altered affect. Cholinergic hippocampal and neocortical systems were chemically and physiologically abnormal in the aged. The implications for slowed cognitive processing and persistance of the memory trace are presented.

Age-Related Changes in Scleral Material Properties of the Monkey Eye

2008 ◽  
Author(s):  
Michaël J. A. Girard ◽  
Jun-Kyo F. Suh ◽  
Michael Bottlang ◽  
Claude F. Burgoyne ◽  
J. Crawford Downs
Keyword(s):  
Intraocular Pressure ◽  
Material Properties ◽  
Lamina Cribrosa ◽  
Collagen Fibers ◽  
Visual Signals ◽  
Type I ◽  
Retinal Ganglion ◽  
Age Related ◽  
The Brain ◽  
Age Related Changes

The sclera is the outer shell and principal load-bearing tissue of the eye, which consists primarily of avascular lamellae of collagen fibers. Ninety percent of the collagen fibers in the sclera are Type I, which provide the eye with necessary mechanical strength to sustain intraocular pressure (IOP). In the posterior sclera, there is a fenestrated canal, called the optic nerve head (ONH), through which the retinal ganglion cell axons pass transmitting visual signals from the retina to the brain. The opening of the ONH is structurally supported by a fenestrated connective tissue called the lamina cribrosa.

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