Developmental changes in associations between auditory-visual events

The goal of the present study was twofold: to examine the influence of two amodal properties, co-location and temporal synchrony, on infants' associating a sight with a sound, and to determine if the relative influence of these properties on crossmodal learning changes with age. During familiarization 2-, 4-, 6- and 8-month-olds were presented two toys and a sound, with sights and sounds varying with respect to co-location and temporal synchrony. Following each familiarization phase infants were given a paired preference test to assess their learning of sight-sound associations. Measures of preferential looking revealed age-related changes in the influence of co-location and temporal synchrony on infants' learning sight-sound associations. At all ages, infants could use temporal synchrony and co-location as a basis for associating an auditory with a visual event and, in the absence of temporal synchrony, co-location was sufficient to support crossmodal learning. However, when these cues conflicted there were developmental changes in the influence of these cues on infants' learning auditory-visual associations. At 2 and 4 months infants associated the sounds with the toy that moved in synchrony with the sound's rhythm despite extreme violation of co-location of this sight and sound. In contrast, 6- and 8-month-olds did not associate a specific toy with the sound when co-location and synchrony information conflicted. The findings highlight the unique and interactive effects of distinct amodal properties on infants' learning arbitrary crossmodal relations. Possible explanations for the age shift in performance are discussed.     

Ratio versus difference comparators in choice.

Several theories in the learning literature describe decision rules for performance utilizing ratios and differences. The present paper analyzes rules for choice based on either delays to food, immediacies (the inverse of delays), or rates of food, combined factorially with a ratio or difference comparator. An experiment using the time-left procedure (Gibbon & Church, 1981) is reported with motivational differentials induced by unequal reinforcement durations. The preference results were compatible with a ratio-comparator decision rule, but not with decision rules based on differences. Differential reinforcement amounts were functionally equivalent to changes in delays to food. Under biased reinforcement, overall food rate was increased, but variance in preference was increased or decreased depending on which alternative was favored. This is a Weber law finding that is compatible with multiplicative, scalar sources of variance but incompatible with pacemaker rate changes proportional to food presentation rate.     

Automaintenance without stimulus-change reinforcement: Temporal control of key pecks

Yoked pairs of experimentally naive pigeons were exposed to a modified autoshaping procedure in which key pecking by the leader birds postponed both keylight termination and access to grain for the leader and the follower bird. Key pecking developed and was maintained in all birds and continued through two reversals of roles in the yoked procedure. Although temporal control developed more slowly in follower birds, asymptotic temporal distributions of key pecking were similar for all birds in both leader and follower roles; maximum responding occurred soon after keylight onset and decreased to a minimum prior to reinforcement. Response distributions for both leader and follower birds were described by Killeen's (1975) mathematical model of temporal control. Follower birds received response-independent reinforcement, and the development by these birds of temporal distributions which are minimal immediately prior to reinforcement is without precedent in Pavlovian appetitive conditioning. However, maintenance of key pecking by the leader birds, whose responses postponed both stimulus-change and food reinforcement, supports an interpretation of autoshaped and automaintained key pecking as responding elicited by signaled grain presentation.     

情绪效价可预测性对时间捆绑效应的影响

时间捆绑效应指的是主观上主动动作和动作结果的时间点相互靠近的现象。其中, 时间捆绑效应可分为动作捆绑和结果捆绑, 分别对应主动动作和动作结果的时间点变化。本研究通过一个混合设计实验考察了情绪效价可预测性对时间捆绑效应的影响。情绪效价可预测性(可预测、不可预测)为被试内因素, 刺激模态(听觉刺激、视觉刺激)为被试间因素。结果发现, 情绪效价为可预测时, 结果捆绑在主动按键后产生听觉刺激或视觉刺激都出现了增强, 而动作捆绑仅在产生视觉刺激时才出现增强。结果表明, 情绪效价为可预测时会增强时间捆绑效应, 但该作用在动作捆绑和结果捆绑中存在差异。由于时间捆绑效应是反映主动控制感的主要指标, 本研究结果对先进驾驶辅助系统的交互设计具有一定的参考意义。     

感知社会善念对信任修复的促进：社会距离与时间距离的调节作用

从信任修复的时间阶段模型来看,以往研究主要探讨了信任违背发生后的修复策略及效果,而鲜有研究从违背前的视角对此展开探索。为检验社会善念能否作为信任修复的‘事前’策略及其修复效果的边界条件,本研究采用Somi范式操纵违背方的社会善念,通过让信任方完成信任博弈游戏来考察其感知到的社会善念对信任修复的效果及社会距离与时间距离在其中发挥的调节作用。实验1结果表明,感知社会善念有助于促进受损信任的修复,感知高(vs.低)社会善念的被试修复效果更好;实验2发现社会距离调节了感知社会善念对信任修复的影响,面对社会距离远(vs.近)者的信任违背,感知到高社会善念的被试有更好的修复效果;实验3不仅再次验证了前两个实验的发现,还进一步发现时间距离调节了社会距离与感知社会善念对信任修复的影响,即当社会距离远的违背方回应时间距离短时,感知高社会善念的被试修复效果更好,当社会距离近的违背方回应时间距离长时,感知高社会善念的被试修复效果更好。由此可见,违背发生前信任方感知到违背方的社会善念能在一定程度上修复受损信任,但其效果受到社会距离与时间距离的制约。这些发现对未来探讨信任修复的事前策略及社会善念理论的应用均有一定启示意义。     

时距知觉的动物研究范式及相关神经机制

在探索时距知觉的脑机制的过程中, 相对于人类被试相关研究, 动物研究可以提供较多的药理学、分子生物学、单个神经元电生理学以及光遗传等方面的研究证据。目前较为常用的时距知觉动物研究范式包括时间二分法、峰值间隔法以及低比率差别强化法等。根据不同的研究需求, 动物研究的范式常会进行调整。对时距知觉的动物研究的探讨将基于两方面展开：(1) 常用的时距知觉动物研究范式的介绍及比较; (2) 基于动物研究范式的时距知觉神经机制研究进展, 旨在为深入探索时间知觉的心理学相关研究提供参考。     

About Skinner and time: behavior-analytic contributions to research on animal timing

The article discusses two important influences of B. F. Skinner, and later workers in the behavior-analytic tradition, on the study of animal timing. The first influence is methodological, and is traced from the invention of schedules imposing temporal constraints or periodicities on animals in The Behavior of Organisms, through the rate differentiation procedures of Schedules of Reinforcement, to modern temporal psychophysics in animals. The second influence has been the development of accounts of animal timing that have tried to avoid reference to internal processes of a cognitive sort, in particular internal clock mechanisms. Skinner's early discussion of temporal control is first reviewed, and then three recent theories-Killeen & Fetterman's (1988) Behavioral Theory of Timing; Machado's (1997) Learning to Time; and Dragoi, Staddon, Palmer, & Buhusi's (2003) Adaptive Timer Model-are discussed and evaluated.     

Explaining neurocognitive aging: is one factor enough?

As an introduction to the special issue on neurocognitive factors underlying age effects, we discuss a number of recent developments in the literature on aging. The classic distinction between generalized and process-specific cognitive changes with old age has reappeared in the distinctions between the frontal lobe hypothesis and more differentiated views of neurocognitive aging. We argue that neurological decay in the frontal cortex has important implications for cognitive control, but that the frontal lobe hypothesis does not capture the plethora of changes that characterize aging and incorrectly suggests a unitary effect.     

A Temporal Logic for Sortals

With the past and future tense propositional operators in its syntax, a formal logical system for sortal quantifiers, sortal identity and (second order) quantification over sortal concepts is formulated. A completeness proof for the system is constructed and its absolute consistency proved. The completeness proof is given relative to a notion of logical validity provided by an intensional semantic system, which assumes an approach to sortals from a modern form of conceptualism.