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131.
Glutamate receptor-dependent neural plasticity is thought to be implicated in memory processes. Ionotropic N-methyl-D-aspartate- (NMDA) sensitive and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate- (AMPA) sensitive glutamate receptors have been particularly studied for their role in synaptic plasticity. Drugs can alter AMPA and NMDA receptor neurotransmission by competing for the glutamate site or other sites on these receptor proteins. Variants of the protein subunits forming AMPA and NMDA heteromers contribute to the complexity of pharmacological activity at these receptors. The NMDA receptor has numerous modulatory centers, including the glycine binding site, NR2B protein specific binding site, and an intrachannel (PCP) binding site. In this study, the accuracy and rate of rats performing under a Fixed Consecutive Number (FCN) operant task were measured after administrations of site-selective AMPA and NMDA receptor modulators. Test compounds included two glycine site NMDA agonists [(+)HA 966 and D-cycloserine], two NR2-B site NMDA antagonists (eliprodil and ifenprodil), an NMDA channel blocking antagonist (MK 801), and a competitively acting AMPA receptor antagonist (NBQX). The accuracy of FCN performance was not affected by response-rate-altering doses of (+) HA 966, D-cycloserine, eliprodil, ifenprodil, or NBQX. MK 801, on the other hand, reduced performance accuracy at several doses. These results are consistent with earlier studies suggesting that AMPA antagonists minimally affect working memory and that glycine and NR2B protein-specific modulatory sites may have advantages as targets for the development of medications intended to alter NMDA receptor-mediated transmission. 相似文献
132.
Richter S Maschke M Timmann D Konczak J Kalenscher T Illenberger AR Kalveram K 《Journal of motor behavior》2004,36(1):28-38
The authors investigated adaptation of goal-directed forearm movements to an unknown external viscous force assisting forearm flexion in 6 patients with cerebellar dysfunction and in 6 control participants. Motor performance was generally degraded in cerebellar patients and was markedly reduced under the force condition in both groups. However, patients and controls were able to adapt to the novel force within 8 trials. Only the healthy controls were able to improve motor performance when readapting to a null-force condition. The results indicate that cerebellar patients' motor control system has imprecise estimations of actual limb dynamics at its disposal. Force adaptation may have been preserved because single-joint movements were performed, whereas the negative viscous force alone and no interaction forces had to be compensated. 相似文献
133.
Käll Anton Shafran Roz Andersson Gerhard 《Journal of psychopathology and behavioral assessment》2021,43(3):686-696
Journal of Psychopathology and Behavioral Assessment - Loneliness is a common experience in populations experiencing mental health problems. Associations with symptoms of psychopathology are... 相似文献
134.
135.
Anton A. van Niekerk 《South African Journal of Philosophy》2016,35(2):164-170
In this article the author responds to Brian Penrose’s critical response to his (Van Niekerk’s) article “Biomedical enhancement and the pursuit of mastery and perfection: a critique of the views of Michael Sandel” that appeared in the PSSA conference edition of the SAJP 33(2), 2014. While Van Niekerk is appreciative of the opportunity for spirited dialogue that Penrose’s response provides, he nevertheless takes issue with several charges Penrose raises. He responds to Penrose’s claims that Van Niekerk does not fully understand “the Sandel project” and thus that Van Niekerk creates and shoots down a straw man in his argument against Sandel. Van Niekerk argues that Penrose’s claims are indicative of significant methodological differences between their respective approaches. Penrose acknowledges the “fuzziness” of Sandel’s arguments with regards to biomedical enhancement. He then develops an interpretation of Sandel’s views that claims to have “filled in the complete picture” of what Sandel attempts to do, and then reproaches Van Niekerk for not responding to that “completed picture”, i.e. the “Sandel project”. Van Niekerk finds this to be an unreasonable and methodologically highly problematic demand on him. Van Niekerk responds to a number of Penrose’s arguments, and then concludes that while there are, of course, good reasons to exercise caution at the prospect of biomedical enhancement with regard to its risks, the possibilities offered by enhancement need not elicit a prima facie reaction of pessimism. Rather, such prospects can also be regarded in a positive light as an exciting opportunity to take our own evolution in hand. 相似文献
136.
Katharina Dinica Liliana Ramona Demenescu Anton Lord Anna Linda Krause Roselinde Kaiser Dorothea Horn 《Cognition & emotion》2016,30(8):1461-1469
People with low Self-directedness (SD) tend to explain their behaviour as being significantly influenced by events in the external environment. One important dimension of external cues is their level of salience: highly salient external stimuli are more likely to capture attention, even when such stimuli are not relevant to goals. We examined whether adults reporting low SD would exhibit greater susceptibility to distraction by highly salient external stimuli. Fifty-four (42 males) subjects completed the Attention Modulation by Salience Task (AMST) measuring reaction times to early- or late-onset auditory stimuli in the presence of high- or low-salience visual distractors. SD was assessed via self-report, and analyses tested the relationship between SD and performance on the AMST. Results showed a slowed early response to auditory cues during high salience compared to low salience. Indeed, individuals reporting low SD showed stronger salience interference, suggesting that external causality attribution is accompanied by a subconscious perceptual deficit. 相似文献
137.
The present study analyzed the factorial structure of the I7 Impulsiveness questionnaire (Impulsiveness, Venturesomeness and Empathy) with a Spanish sample of 742 males and 1.075 females, through exploratory and confirmatory factorial analysis. In relation to the original English data, a three-factor structure showed global congruency coefficients of 0.92 and 0.94 for men and women. Venturesomeness had a modest congruency for males (0.83). A cross-validation analytical strategy showed that the 24-item I7 was invariant only for the female sample. A subsequent exploratory factor analysis with 24 items showed a sound factor structure. The 24-item version showed the best and most robust structure and similar internal consistency coefficients in regard to the 54-item version. No important differences were founded between I7 long and short versions with impulsiveness scales of ZKPQ, BIS-10 and SPSRQ. 相似文献
138.
Rossier J Aluja A García LF Angleitner A De Pascalis V Wang W Kuhlman M Zuckerman M 《Journal of personality assessment》2007,89(2):188-196
The aim of this study was to analyze the cross-cultural generalizability of the Alternative five-factor model (AFFM; Zuckerman, Kuhlman, & Camac, 1988). The total sample was made up of 9,152 subjects from six countries: China, Germany, Italy, Spain, Switzerland, and the United States. The internal consistencies for all countries were generally similar to those found for the normative American sample. Factor analyses within cultures showed that the normative American structure was replicated in all cultures; however, the congruence coefficients were slightly lower in China and Italy. A similar analysis at the facet level confirmed the high cross-cultural replicability of the AFFM. Mean-level comparisons did not always show the hypothesized effects. The mean score differences across countries were very small. 相似文献
139.
Scores on Extraversion and on Neuroticism as measured by the Eysenck Personality Inventory were compared for 90 undergraduate team sport participants, individual sport participants, and nonparticipants (43 men, 47 women, M age = 20.3 yr.). From past research and Eysenck's biological theory of personality, it was hypothesized that sport participants would score higher on Extraversion and lower on Neuroticism than nonparticipants, and that team participants would score higher on Extraversion and perhaps higher on Neuroticism than individual sport participants. By comparing scores for students in first year and final year, it was also investigated whether pre-existing personality differences drew people to sport (the gravitational hypothesis) or whether personality changed as a function of sport participation (the developmental hypothesis). The main findings were that team participants scored higher on Extraversion than both individual sport participants and nonparticipants, and that test scores did not change over time, supporting the gravitational hypothesis for Extraversion. 相似文献
140.
Working memory deficits in transgenic rats overexpressing human adenosine A2A receptors in the brain
Giménez-Llort L Schiffmann SN Shmidt T Canela L Camón L Wassholm M Canals M Terasmaa A Fernández-Teruel A Tobeña A Popova E Ferré S Agnati L Ciruela F Martínez E Scheel-Kruger J Lluis C Franco R Fuxe K Bader M 《Neurobiology of learning and memory》2007,87(1):42-56
Adenosine receptors in the central nervous system have been implicated in the modulation of different behavioural patterns and cognitive functions although the specific role of A(2A) receptor (A(2A)R) subtype in learning and memory is still unclear. In the present work we establish a novel transgenic rat strain, TGR(NSEhA2A), overexpressing adenosine A(2A)Rs mainly in the cerebral cortex, the hippocampal formation, and the cerebellum. Thereafter, we explore the relevance of this A(2A)Rs overexpression for learning and memory function. Animals were behaviourally assessed in several learning and memory tasks (6-arms radial tunnel maze, T-maze, object recognition, and several Morris water maze paradigms) and other tests for spontaneous motor activity (open field, hexagonal tunnel maze) and anxiety (plus maze) as modification of these behaviours may interfere with the assessment of cognitive function. Neither motor performance and emotional/anxious-like behaviours were altered by overexpression of A(2A)Rs. TGR(NSEhA2A) showed normal hippocampal-dependent learning of spatial reference memory. However, they presented working memory deficits as detected by performance of constant errors in the blind arms of the 6 arm radial tunnel maze, reduced recognition of a novel object and a lack of learning improvement over four trials on the same day which was not observed over consecutive days in a repeated acquisition paradigm in the Morris water maze. Given the interdependence between adenosinic and dopaminergic function, the present results render the novel TGR(NSEhA2A) as a putative animal model for the working memory deficits and cognitive disruptions related to overstimulation of cortical A(2A)Rs or to dopaminergic prefrontal dysfunction as seen in schizophrenic or Parkinson's disease patients. 相似文献