The emulation theory of representation: motor control, imagery, and perception

The emulation theory of representation is developed and explored as a framework that can revealingly synthesize a wide variety of representational functions of the brain. The framework is based on constructs from control theory (forward models) and signal processing (Kalman filters). The idea is that in addition to simply engaging with the body and environment, the brain constructs neural circuits that act as models of the body and environment. During overt sensorimotor engagement, these models are driven by efference copies in parallel with the body and environment, in order to provide expectations of the sensory feedback, and to enhance and process sensory information. These models can also be run off-line in order to produce imagery, estimate outcomes of different actions, and evaluate and develop motor plans. The framework is initially developed within the context of motor control, where it has been shown that inner models running in parallel with the body can reduce the effects of feedback delay problems. The same mechanisms can account for motor imagery as the off-line driving of the emulator via efference copies. The framework is extended to account for visual imagery as the off-line driving of an emulator of the motor-visual loop. I also show how such systems can provide for amodal spatial imagery. Perception, including visual perception, results from such models being used to form expectations of, and to interpret, sensory input. I close by briefly outlining other cognitive functions that might also be synthesized within this framework, including reasoning, theory of mind phenomena, and language.     

The problem of redundancy in movement control: The adaptive model theory approach

Summary The problem of redundancy in movement control is encountered when one attempts to answer the question: How does the central nervous system (CNS) determine the pattern of neural activity required in some 5,000,000 descending motor fibres to control only 100–150 biomechanical degrees of freedom of movement? Mathematically this is equivalent to solving a set of simultaneous equations with many more unknowns than equations. This system of equations is redundant because it has an infinite number of possible solutions. The problem is solved by the neuronal circuitry hypothesized in Adaptive Model Theory (AMT). According to AMT, the CNS includes neuronal circuitry able to compute and maintain adaptively the accuracy of internal models of the reciprocal multivariable relationships between outgoing motor commands and their resulting sensory consequences. To identify these input-output relationships by means of regression analysis, correlations between the input signals have to be taken into account. For example, if the inputs are perfectly correlated, the model reduces to a virtual one-input system. In general, the number of inputs modelled equals the number of degrees of freedom encoded by the signals; that is, the number of independently varying (orthogonal) signals. The adaptive modelling circuitry proposed in AMT automatically tunes itself to extract independently varying sensory and motor signals before computing the dynamic relationships between them. Inverse models are employed during response execution to translate movements preplanned as desired trajectories of these high-level sensory-feature signals into appropriately co-ordinated motor commands to send to the muscles. Since movement is preplanned in terms of a number of orthogonalized sensory-feature signals equal to the number of degrees of freedom in the desired response, the problem of redundancy is solved and the correlation or co-ordination between motor-command signals is automatically introduced by the adaptive models.     

Anxiety and cognitive performance: attentional control theory

Attentional control theory is an approach to anxiety and cognition representing a major development of Eysenck and Calvo's (1992) processing efficiency theory. It is assumed that anxiety impairs efficient functioning of the goal-directed attentional system and increases the extent to which processing is influenced by the stimulus-driven attentional system. In addition to decreasing attentional control, anxiety increases attention to threat-related stimuli. Adverse effects of anxiety on processing efficiency depend on two central executive functions involving attentional control: inhibition and shifting. However, anxiety may not impair performance effectiveness (quality of performance) when it leads to the use of compensatory strategies (e.g., enhanced effort; increased use of processing resources). Directions for future research are discussed.     

焦虑个体抑制控制缺陷的研究现状和争议：基于注意控制理论视角

根据注意控制理论的观点, 焦虑会削弱个体的抑制控制功能。虽然这一假设得到了大量行为学和神经生理证据的支撑, 但在高焦虑个体是增加还是减少自上而下注意控制资源来完成抑制控制任务这一核心问题上却存在较大争议。多种因素的存在造成了这一局面。理论解释本身存在明显的不足; 实证研究中多种额外变量的存在导致已有研究结果的信效度较低。未来可以通过探索焦虑水平、注意控制水平和抑制控制之间的关系来解决这一争议。     

Stimulus control topography coherence theory: foundations and extensions

Stimulus control topography refers to qualitative differences among members of a functional stimulus class. Stimulus control topography coherence refers to the degree of concordance between the stimulus properties specified as relevant by the individual arranging a reinforcement contingency (behavior analyst, experimenter, teacher, etc.) and the stimulus properties that come to control the behavior of the organism (experimental subject, student, etc.) that experiences those contingencies. This paper summarizes the rationale for analyses of discrimination learning outcomes in terms of stimulus control topography coherence and briefly reviews some of the foundational studies that led to this perspective. We also suggest directions for future research, including pursuit of conceptual and methodological challenges to a complete stimulus control topography coherence analysis of processes involved in discriminated and generalized operants.     

The role of control functions in mentalizing: dual-task studies of theory of mind and executive function

Conflicting evidence has arisen from correlational studies regarding the role of executive control functions in Theory of Mind. The current study used dual-task manipulations of executive functions (inhibition, updating and switching) to investigate the role of these control functions in mental state and non-mental state tasks. The 'Eyes' pictorial test of Theory of Mind showed specific dual-task costs when concurrently performed with an inhibitory secondary task. In contrast, interference effects on a verbal 'Stories' task were general, occurring on both mental state and non-mental state tasks, and across all types of executive function. These findings from healthy functioning adults should help to guide decisions about appropriate methods of assessing ToM in clinical populations, and interpreting deficits in performance in such tasks in the context of more general cognitive dysfunction.     

Goal theory vs. control theory: Contrasting approaches to understanding work motivation

Control theory has been propounded as an original and useful paradigm for integrating a number of theories of human (especially work) motivation. This paper challenges that claim. First, it is shown that the original, mechanical control theory model is not applicable to human beings. Second, it is shown that the two approaches used by control theorists to remedy its limitations did not succeed. One approach involved incorporating propositions drawn from other theories with the result that there was nothing distinctive left that was unique to control theory. The other approach involved broadening the scope of control theory by adding deduced propositions; however, these propositions were inconsistent with what was already known about the phenomena in question based on empirical research. The control theory approach to theory building is contrasted with that of goal setting theory (Locke & Latham, 1990). Goal-setting theory is a grounded theory (Glaser & Strauss, 1967) which evolved from research findings over a 25-year period. Goal theory developed in five directions simultaneously: validation of the core premises; demonstrations of generality; identification of moderators; conceptual refinement and elaboration; and integration with other theories. It is hypothesized that the grounded theory approach is a more fruitful one than the approaches used by control theory.The author wishes to thank Judy Olian for her helpful comments on this paper and Dong-OK Chah for making the figures.     

Development of theory of mind and executive control

Several recent studies have demonstrated a developmental link, in the age range of 3–5 years, between the acquisition of a ‘theory of mind’ and self control. In this review, we consider the existence of such a link in assessing five competing theoretical hypotheses that might help us to understand the nature of this developmental advance: (1) executive control depends on theory of mind; (2) theory of mind development depends on executive control; (3) the relevant theory of mind tasks require executive control; (4) both kinds of task require the same kind of embedded conditional reasoning; (5) theory of mind and executive control involve the same brain region. We briefly describe these theoretical accounts and evaluate them in the light of existing empirical evidence. At present, only account (3) can be ruled out with some confidence.     

Beliefs about birth control: a consistency theory analysis

201 lower income women aged 20-40 were interviewed in a large midwestern city in December 1967 and January 1968 to determine attitudes towards, beliefs about, and use of birth control. Those who approved of birth control had more positive beliefs about the consequences of birth control than those with less favorable attitudes. Users of reliable methods also held more positive attitudes about birth control consequences than nonusers or users of nonreliable methods although this relationship was weak. Strategies for improving family planning behavioral predictions are suggested as well as implications of this for family planning communication programs.     

Load theory of selective attention and cognitive control

A load theory of attention in which distractor rejection depends on the level and type of load involved in current processing was tested. A series of experiments demonstrates that whereas high perceptual load reduces distractor interference, working memory load or dual-task coordination load increases distractor interference. These findings suggest 2 selective attention mechanisms: a perceptual selection mechanism serving to reduce distractor perception in situations of high perceptual load that exhaust perceptual capacity in processing relevant stimuli and a cognitive control mechanism that reduces interference from perceived distractors as long as cognitive control functions are available to maintain current priorities (low cognitive load). This theory resolves the long-standing early versus late selection debate and clarifies the role of cognitive control in selective attention.     

Anxiety,anticipation and contextual information: A test of attentional control theory

We tested the assumptions of Attentional Control Theory (ACT) by examining the impact of anxiety on anticipation using a dynamic, time-constrained task. Moreover, we examined the involvement of high- and low-level cognitive processes in anticipation and how their importance may interact with anxiety. Skilled and less-skilled tennis players anticipated the shots of opponents under low- and high-anxiety conditions. Participants viewed three types of video stimuli, each depicting different levels of contextual information. Performance effectiveness (response accuracy) and processing efficiency (response accuracy divided by corresponding mental effort) were measured. Skilled players recorded higher levels of response accuracy and processing efficiency compared to less-skilled counterparts. Processing efficiency significantly decreased under high- compared to low-anxiety conditions. No difference in response accuracy was observed. When reviewing directional errors, anxiety was most detrimental to performance in the condition conveying only contextual information, suggesting that anxiety may have a greater impact on high-level (top-down) cognitive processes, potentially due to a shift in attentional control. Our findings provide partial support for ACT; anxiety elicited greater decrements in processing efficiency than performance effectiveness, possibly due to predominance of the stimulus-driven attentional system.     

On feeling in control: a biological theory for individual differences in control perception

This review aims to create a cross-disciplinary framework for understanding the perception of control. Although, the personality trait locus of control, the most common measure of control perception, has traditionally been regarded as a product of social learning, it may have biological antecedents as well. It is suggested that control perception follows from the brain's capacity for self regulation, leading to flexible and goal directed behaviours. To this account, a model is presented which spans several levels of analyses. On a behavioural level, control perception may be a corollary of emotion regulation, executive functions, and social cognition. On a neural level, these self-regulatory functions are substantiated in part by the dorsolateral and ventral prefrontal cortex and the anterior cingulate cortex. In addition, a possible role of subcortical-cortical dopamine pathways underlying control perception is discussed.     

The value of children: theory and method

Psychological research into the determinants of family size pertains to the motivations connected with childbearing in general and to those relating to specific numbers of children or family size. 1 model defines the variables affecting such motivations as: 1) the value of children; 2) alternate sources of value; 3) costs, 4) barriers, and 5)facilitators. An ongoing cross cultural study is discussed and the questionnaires used in the study as well as the preliminary results are given. It is felt that the knowledge gained through such research will help in the design of social policies that influence couples to regulate family size to levels that are congruent with personal desires as well as societal goals.     

A theory of intelligence: I. span and the complexity of stimulus control

A theory of intelligence is couched in stimulus-response terms, bridging the gap between S-R and cognitive psychology. The chief theoretical concepts are span ability (a capacity notion), response string (sequentially cued responses), and complexity of stimulus control (task complexity). Span is equated with the ability to respond appropriately when several cues are conjunctively relevant for correct performance (complex stimulus control). So defined, span is consistently and broadly related to many aspects of intelligent behavior.     

techniques of neutralization and self-esteem: a critical test of social control and neutralization theory

Sykes and Matza argued that delinquents use techniques of neutralization to enable themselves to engage in behavior they believe is wrong under most circumstances. One function of using these techniques is that the individual is able to protect his or her self-concept while committing delinquent acts. This implies that delinquent youth who use these techniques should have higher levels of self-esteem than delinquents who do not use them. Because Sykes and Matza hold that neutralization is necessary because of the delinquents ties to conventional society, this effect should be stronger among delinquent youth who are more strongly attached to their parents. In contrast, Hirschis social control theory predicts that delinquents who are able to maintain a bond to conventional society should be less likely to neutralize, but if they do neutralize, they should be unable to sufficiently convince themselves of the validity of the neutralizations to protect self-esteem. These hypotheses are tested using data from the Richmond Youth Survey. The results differed depending on whether general neutralizations or neutralizations regarding the police were analyzed. Children who are attached to their parents are less likely to use police-related neutralizations, but delinquents who use these neutralizations have higher self-esteem, consistent with neutralization theory. Delinquents who are more strongly attached to their parents are also less likely to use general neutralizations, but these neutralization techniques do not lead to higher levels of self-esteem, consistent with control theory.     

A control theory of sequential response production

Summary Response bias as it occurs in sequential response production, especially in response randomization tasks, is an intriguing problem. The strength theory, which predicts that responses are produced because of their strength or availability in memory, can explain only a fraction of the phenomena of response bias. Two other theoretical approaches need special attention. The first is the concept hypothesis which suggests that response bias is the result of subjective randomness in producing a random sequence. The second is the control hypothesis which suggests that response bias is the result of attempts on the part of the subjects to control perseverations and stereotypes.Unfortunately, there is a lack of experimental evidence to support the concept hypothesis in randomization. The control hypothesis seems a better theory for explaining various instances of response bias. An additional theoretical advantage of the control hypothesis is that it can also explain response bias in areas of sequential response bias other than randomization.