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81.
82.
Mark A. Bedau 《Synthese》2012,185(1):73-88
This paper describes and defends the view that minimal chemical life essentially involves the chemical integration of three
chemical functionalities: containment, metabolism, and program (Rasmussen et al. in Protocells: bridging nonliving and living
matter, 2009a). This view is illustrated and explained with the help of CMP and Rasmussen diagrams (Rasmussen et al. In: Rasmussen et al.
(eds.) in Protocells: bridging nonliving and living matter, 71–100, 2009b), both of which represent the key chemical functional dependencies among containment, metabolism, and program. The CMP model
of minimal chemical life gains some support from the broad view of life as open-ended evolution, which I have defended elsewhere
(Bedau in The philosophy of artificial life, 1996; Bedau in Artificial Life, 4:125–140, 1998). Further support comes from the natural way the CMP model resolves the puzzle about whether life is a matter of degree. 相似文献
83.
Recent research has demonstrated a relationship between retrieval organization and the efficacy of prior repeated retrieval
on delayed tests. The present study asked why repeated study engenders higher recall at a short delay despite lower retrieval
organization but produces a decline at a long delay, and why repeated retrieval engenders lower recall at a short delay despite
higher retrieval organization but produces stable recall over time. This relationship was examined through the inclusion of
two successive recall tests—one immediately after learning method and one a week later. Results replicated the interaction
in recall between learning method and delay characterizing the testing effect and, critically, revealed the qualitative differences
inherent in the retrieval organization of each method. Specifically, stable recall in repeated retrieval was accompanied by
strong and sustained conceptual organization, whereas organization for repeated study was tenuous and weakened across tests.
These differences quantitatively were assessed through the use of five targeted analyses: specifically, the examination of
cumulative recall curves, the accumulation of organization across time (a curve akin to cumulative recall), item gains and
losses across time, changes in the size of categories across time, and the fate of specific clusters of recalled items across
time. These differences are discussed within the context of differential processes occurring during learning method. 相似文献
84.
In two experiments, participants navigated through a large arena within a virtual environment (VE) to a location encoded in memory from a map. In both experiments, participants recalled locations by navigating through the VE, but in Experiment 2, they additionally recalled the locations on the original map. Two cues were located outside and above the walls of the arena at either north-south locations or east-west locations. The pattern of angular bias was used to infer how the cues affected the creation of spatial categories influencing memory for location in the two tasks. When participants navigated to remembered locations in the VE, two cue-based spatial categories were inferred, with cues serving to demarcate the boundaries of the categories. When participants remembered locations on the original map, two cue-based categories were again formed, but with cues serving as category prototypes. The pattern of results implies that cue-based spatial categorization schemes may be formulated differently at the memory retrieval stage depending on task constraints. 相似文献
85.
Some situations require one to quickly stop an initiated response. Recent evidence suggests that rapid stopping engages a mechanism that has diffuse effects on the motor system. For example, stopping the hand dampens the excitability of the task-irrelevant leg. However, it is unclear whether this ‘global suppression’ could apply across wider motor modalities. Here we tested whether stopping speech leads to suppression of the task-irrelevant hand. We used Transcranial Magnetic Stimulation over the primary motor cortex with concurrent electromyography from the hand. We found that when speech was successfully stopped the motor evoked potential from the task-irrelevant hand was significantly reduced compared to when the participant failed to stop speaking, or responded on non stop signal trials, or compared to baseline. This shows that when speech is quickly stopped, there is a broad suppression across the motor system. This has implications for the neural basis of speech control and stuttering. 相似文献
86.
The ability to identify an unfamiliar target face from an identity lineup declines when the target is accompanied by a second face during visual encoding. This two-face disadvantage is still little studied and its basis remains poorly understood. We investigated several possible explanations for this phenomenon. Experiments 1 and 2 varied the number of potential targets (1 or 2) and the number of faces in a lineup (5 or 10) to explore if this effect arises from the number of identity comparisons that need to be made to detect a target in a lineup. We also explored if this effect arises from an uncertainty concerning which is the to-be-identified target in two-face displays, by cueing the relevant face during encoding. In experiment 3 we then examined whether the two-face disadvantage reflects the depth of face encoding or a memory effect. The results show that this effect arises from the additional comparisons that are necessary to compare two potential targets to an identity lineup when memory demands are minimised (experiment 1), but it reflects a difficulty in remembering several faces when targets and lineups cannot be viewed simultaneously (experiments 2 and 3). However, in both cases the two-face disadvantage could not be eliminated fully by cueing the target. This hints at a further possible locus for this effect, which might reflect perceptual interference during the initial encoding of the target. The implications of these findings are discussed. 相似文献
87.
The action abilities of an individual observer modulate his or her perception of spatial properties of the environment and of objects. The present study investigated how joint action abilities shape perception. Four experiments examined how the intention to lift an object with another individual affects perceived weight. In Experiments 1, 2a, and 2b, participants judged the perceived weight of boxes while expecting to lift them either alone or with a co-actor. In Experiment 3, the co-actor was healthy or injured. Participants intending to lift a box with a co-actor perceived the box as lighter than participants intending to lift the same box alone, provided that the co-actor appeared healthy and therefore capable of helping. These findings suggest that anticipated effort modulates the perception of object properties in the context of joint action. We discuss implications for the role of action prediction and action simulation processes in social interaction. 相似文献
88.
Current evolutionary and cognitive theories of religion posit that supernatural agent concepts emerge from cognitive systems such as theory of mind and social cognition. Some argue that these concepts evolved to maintain social order by minimizing antisocial behavior. If these theories are correct, then people should process information about supernatural agents' socially strategic knowledge more quickly than non-strategic knowledge. Furthermore, agents' knowledge of immoral and uncooperative social behaviors should be especially accessible to people. To examine these hypotheses, we measured response-times to questions about the knowledge attributed to four different agents--God, Santa Claus, a fictional surveillance government, and omniscient but non-interfering aliens--that vary in their omniscience, moral concern, ability to punish, and how supernatural they are. As anticipated, participants respond more quickly to questions about agents' socially strategic knowledge than non-strategic knowledge, but only when agents are able to punish. 相似文献
89.
Ryan L. Boyd Michael D. Robinson Adam K. Fetterman 《Journal of experimental social psychology》2011,47(6):1192-1197
Three experiments (total N = 291) sought to provide support for the idea that avoidance conflicts, relative to approach conflicts, are more difficult to motorically resolve. Conflicts were instantiated by asking individuals to approach desirable stimuli and avoid undesirable stimuli under conditions in which there was no objectively-correct direction of movement. To control for baseline movement speeds, non-conflict trials presented desirable (e.g., reward) and undesirable (e.g., threat) stimuli in the absence of any spatial conflict. In addition, movement times were isolated through the use of a joystick movement paradigm in which movement speeds were quantified subsequent to some initial tendency to move in one direction or the other. Consistent with hypotheses, all experiments found that movement times were slowed in the context of avoidance conflicts relative to approach conflicts. Results are discussed in terms of theories of motivation, affective processing, conflict, and anxiety. 相似文献
90.
The interaction between redundant geometric and featural cues in open field search tasks has been examined widely with results that are not always consistent. Cheng (1986) found evidence that when searching for food in rectangular environments, rats used the geometrical characteristics of the environment rather than local featural cues, suggesting that geometry had overshadowed featural cues. More recently, Graham et al. (2006) and Pearce et al. (2006) found that wall color facilitated (potentiated) learning about the shape of the environment by rats in a kite-shaped water maze. The first experiment in the present research replicated the paradigm used by Graham et al. and Pearce et al. using rats in a foraging situation, but with conditions similar, and found the same results, potentiation of shape by color. Experiments 2 and 3 revealed overshadowing instead of potentiation of shape by wall color under the same conditions except that the wall colors of the test environment were not the same as those used during training. The results are consistent with an analysis of the role of associations formed between wall color and geometry in such situations (Rhodes et al., 2009) and extend our understanding of how featural and spatial cues interact. 相似文献