Muscarinic M1, but not M4, receptor antagonism impairs divided attention in male rats

2021 ◽  
Author(s):  
Paige Nicklas ◽  
Miranda Lynn Kiefer ◽  
Mikaela Whalen ◽  
Maeve Stewart ◽  
Deandra E. Mosura ◽  
...  

Divided attention may be more important than ever to comprehend, given ubiquitous distractors in modern living. In humans, concern has been expressed about the negative impact of distraction in education, the home, and the workplace. While acetylcholine supports divided attention, in part via muscarinic receptors, little is known about the specific muscarinic subtypes that may contribute. We designed a novel, high-response rate test of auditory sustained attention, in which rats complete variable-ratio runs on one of two levers, rather than emitting a single response. By doing this, we can present a secondary visual distractor task during some trials, for which a correct nosepoke response is reinforced with a more palatable food pellet. The nonspecific muscarinic antagonist scopolamine impaired performance, and slowed and reduced lever press activity. We then explored antagonists that preferentially block the M1 and M4 subtypes, because these receptors are potential therapeutic targets for cognitive enhancers. Telenzepine, an M1-preferring antagonist, impaired divided attention performance, but not performance of the attention task without distraction. Telenzepine also had fewer nonspecific effects than scopolamine. In contrast, the M4-preferring antagonist tropicamide had no effects. Analysis of overall behavior also indicated that accuracy in the main attention task decreased as a function of engagement with the distractor task. These results implicate the M1 receptor in divided attention.

2005 ◽  
Vol 16 (4) ◽  
pp. 235-242 ◽  
Author(s):  
Astrid von Bueren Jarchow ◽  
Bogdan P. Radanov ◽  
Lutz Jäncke

Abstract: The aim of the present study was to examine to what extent chronic pain has an impact on various attentional processes. To measure these attention processes a set of experimental standard tests of the “Testbatterie zur Aufmerksamkeitsprüfung” (TAP), a neuropsychological battery testing different levels of attention, were used: alertness, divided attention, covert attention, vigilance, visual search, and Go-NoGo tasks. 24 chronic outpatients and 24 well-matched healthy control subjects were tested. The control subjects were matched for age, gender, and education. The group of chronic pain patients exhibited marked deficiencies in all attentional functions except for the divided attention task. Thus, the data supports the notion that chronic pain negatively influences attention because pain patients` attention is strongly captivated by the internal pain stimuli. Only the more demanding divided attention task has the capability to distract the focus of attention to the pain stimuli. Therefore, the pain patients are capable of performing within normal limits. Based on these findings chronic pain patients' attentional deficits should be appropriately evaluated and considered for insurance and work related matters. The effect of a successful distraction away from the pain in the divided attention task can also open new therapeutic aspects.


2003 ◽  
Vol 14 (4) ◽  
pp. 283-292 ◽  
Author(s):  
W. Sturm ◽  
B. Fimm ◽  
A. Cantagallo ◽  
N. Cremel ◽  
P. North ◽  
...  

Abstract: In a multicenter European approach, the efficacy of the AIXTENT computerized training programs for intensity aspects (alertness and vigilance) and selectivity aspects (selective and divided attention) of attention was studied in 33 patients with brain damage of vascular and traumatic etiology. Each patient received training in one of two most impaired of the four attention domains. Control tests were performed by means of a standardized computerized attention test battery (TAP) comprising tests for the four attention functions. Assessment was carried out at the beginning and at the end of a four week baseline period and after the training period of 14 one-hour sessions. At the end of the baseline phase, there was only slight but significant improvement for the most complex attention function, divided attention (number of omissions). After the training, there were significant specific training effects for both intensity aspects (alertness and vigilance) and also for the number of omissions in the divided attention task. The application of inferential single case procedures revealed a high number of significant improvements in individual cases after specific training of alertness and vigilance problems. On the other hand, a non specific training addressing selectivity aspects of attention lead either to improvement or deterioration of alertness and vigilance performance. The results corroborate the findings of former studies with the same training instrument but in patients with different lesion etiologies.


2015 ◽  
Vol 47 (5) ◽  
pp. 378-385 ◽  
Author(s):  
Sheila de Melo Borges ◽  
Márcia Radanovic ◽  
Orestes Vicente Forlenza

1970 ◽  
Vol 36 (1) ◽  
pp. 103-109 ◽  
Author(s):  
S Talukder ◽  
MA Hossain ◽  
S Sarker ◽  
MAH Khan

To evaluate the antifertility effect of crude mixture of A. precatorius seeds at the dose level of 50 mg/kg body weight in adult male rats, after oral administration to male rats for 40 days, the rats were sacrificed and hormonal profiles, serum biochemistry, sperm count and histological changes were recorded. A sharp decrease in the serum levels of testosterone (0.70 ± 0.17 ng/ml), FSH (0.70 ± 0.22 lU/L), and LH (0.87 ± 0.35 IU/L) was detected compared to control (FSH, LH and testosterone levels 0.93 ± 0.15 ng/ml, 0.76 ± 0.28 IU/L, 1.44 ± .011 IU/L, respectively). A significant reduction of epididymal sperm count (2.34 million/mL) was noted in treated rats as compared to control group (7.87 million/mL). Histology of testes showed marked atrophy of the testes, which was characterized by disruption of the seminiferous epithelium and atrophy of the Leydig cells. Crude mixture of A. precatorius seed has a negative impact on male reproductive functions. It might be suggested that crude mixture of A. precatorius seeds might have antifertility property for male rats.   Keywords: Abrus precatorius; antifertility; male rat; testosterone. DOI: http://dx.doi.org/10.3329/bjar.v36i1.9234 BJAR 2011; 36(1): 103-109


2021 ◽  
Vol 6 (2) ◽  
pp. 227-235
Author(s):  
O. Litovchenko ◽  
◽  
I. Perova ◽  

In modern conditions there is a high need to improve methods for establishing the nature of the combined influence of factors using modern approaches for further development of prevention measures against the negative impact of factors on the body. The purpose of the study was to investigate the combined effect of electromagnetic radiation and low temperatures with subsequent determination of the level of contribution of each factor in the formation of biological effects within the experiment by mathematical analysis of data using the method of artificial intelligence. Materials and methods. The subchronic experiment (30 days) was performed on male rats. The animals were divided into groups: combined exposure to electromagnetic radiation (70 kHz, 600 V/m) and reduced temperature (40C), isolated exposure to reduced temperature, isolated exposure to electromagnetic radiation and a control group. The establishment of biological effects was performed at stages 5, 15 and 30 days of the experiment. Changes in the body were assessed by physiological, biochemical and immunological parameters of the blood (30 indicators). Data processing was performed using computational intelligence methods (Neuro-fuzzy system). Results and discussion. The combined effect of the factors was manifested by the following biological effects: intensification of peroxidation processes with simultaneous moderate suppression of antioxidant protection, intensification of lipid metabolism was characterized by dyslipoproteinemia, manifesting in: increase in triglycerides, cholesterol and its fractions. Changes of the immune system were decrease in the ability of neutrophils to phagocytosis at different stages of the experiment, imbalance of the activation of the system of reducing the concentration of C4 at the background of increased intensity of IgM and IgG synthesis. The method of determining the intensity of the factors, developed on the basis of factor and cluster analysis, allowed to determine that during the experiment the ratios between the factors changed, but the greatest contribution was made by reduced temperature by both biochemical parameters (63%) and immunological (53%) at the same time, the level of electromagnetic radiation contribution was 37% and 47%, respectively. Thus, the reduced temperature was the leading factor in the combined effect, which added 60% to the overall biological effect throughout the study, against the effect of electromagnetic radiation for which the level of contribution was only 40%. By means of the factor analysis informative indicators, making it possible to establish the characteristics of biological effects, and therefore leading indicators in formation of biological effects were the increase in concentration of DC with simultaneous decrease in concentration of SH-groups, increase in VLDL and suppression of oxygen-dependent metabolism of neutrophil-test. Conclusion. Thus, the tested mathematical approach allowed to determine the leading role of each of the studied factors under the conditions of their combined influence in different systems, which allows to predict probable appropriate reactions of the whole organism and gives a reasonable approach to the development of preventive measures


1977 ◽  
Vol 29 (1) ◽  
pp. 107-116 ◽  
Author(s):  
John Long

Detection and recognition studies are reviewed, which show a dependency between errors on successive trials. They suggest the impairment accompanying the presentation of simultaneous signals may also involve a similar “between-trial” component. The hypothesis was tested using a two-choice recognition paradigm with bimodal signals. Dimensions presented simultaneously were interleaved on alternate trials with a single dimension presented alone. Interleaving two signals in the first experiment showed no effect on the following signal presented alone, compared to a control condition in which the signal always preceded itself. Interleaving four signals in the second experiment produced a significant impairment. Accounts of the results based on the length of the response interval, fluctuations of state variables such as arousal and decay of the memory trace are rejected. Accounts based on the impairment and set-size of preceding simultaneous signals are retained. Both suppose part of the impairment accompanying simultaneous signals to be a between-trial phenomenon. Implications of the results for work on divided-attention are considered and a method of experimental control proposed.


2007 ◽  
Vol 23 (4) ◽  
pp. 231-240 ◽  
Author(s):  
Shutaro Nakaaki ◽  
Yoshie Murata ◽  
Junko Sato ◽  
Yoshihiro Shinagawa ◽  
Hiroshi Tatsumi ◽  
...  

SLEEP ◽  
2021 ◽  
Author(s):  
Michelle E Stepan ◽  
Erik M Altmann ◽  
Kimberly M Fenn

Abstract Sleeping for a short period (i.e., napping) may help mitigate impairments in cognitive processing caused by sleep deprivation, but there is limited research on effects of brief naps in particular. Here, we tested the effect of a brief nap opportunity (30- or 60-min) during a period of sleep deprivation on two cognitive processes with broad scope, placekeeping and vigilant attention. In the evening, participants (N = 280) completed a placekeeping task (UNRAVEL) and a vigilant attention task (Psychomotor Vigilance Task [PVT]) and were randomly assigned to either stay awake overnight or sleep at home. Sleep-deprived participants were randomly assigned to receive either no nap opportunity, a 30-min opportunity, or a 60-min opportunity. Participants who napped were set up with polysomnography. The next morning, sleep participants returned, and all participants completed UNRAVEL and the PVT. Sleep deprivation impaired performance on both tasks, but nap opportunity did not reduce the impairment, suggesting that naps longer than those tested may be necessary to cause group differences. However, in participants who napped, more time spent in slow-wave sleep (SWS) was associated with reduced performance deficits on both tasks, effects we interpret in terms of the role of SWS in alleviating sleep pressure and facilitating memory consolidation.


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