Large-scale brain networks and psychopathology: a unifying triple network model

The science of large-scale brain networks offers a powerful paradigm for investigating cognitive and affective dysfunction in psychiatric and neurological disorders. This review examines recent conceptual and methodological developments which are contributing to a paradigm shift in the study of psychopathology. I summarize methods for characterizing aberrant brain networks and demonstrate how network analysis provides novel insights into dysfunctional brain architecture. Deficits in access, engagement and disengagement of large-scale neurocognitive networks are shown to play a prominent role in several disorders including schizophrenia, depression, anxiety, dementia and autism. Synthesizing recent research, I propose a triple network model of aberrant saliency mapping and cognitive dysfunction in psychopathology, emphasizing the surprising parallels that are beginning to emerge across psychiatric and neurological disorders.     

Temporal factorisation: A unifying principle for dynamics of the world and of mental states

Dynamics play a major role in many phenomena, addressed in a variety of disciplines. This paper contributes to the identification of common principles underlying approaches to dynamics used within a variety of cognitive and noncognitive disciplines, such as Cognitive Science, Physics, Mathematics, Chemistry, Computer Science and Biology. More specifically, as a central, unifying principle, the temporal factorisation principle is introduced, formalised and illustrated. This principle expresses, that every temporal relationship of the form ‘past pattern implies future pattern’ can be factorised into a relationship of the form ‘past pattern implies present state’ and a relationship of the form ‘present state implies future pattern’. To enable this, for every ‘past pattern implies future pattern’ relationship, the principle postulates the existence of certain mediating state properties in the present state. It provides a conceptual framework which unifies various approaches to dynamics within a variety of disciplines. In particular, it is shown how the principle can be applied in the case of cognitive states of agents.     

Hallucinations in schizophrenia, sensory impairment, and brain disease: a unifying model

Based on recent insight into the thalamocortical system and its role in perception and conscious experience, a unified pathophysiological framework for hallucinations in neurological and psychiatric conditions is proposed, which integrates previously unrelated neurobiological and psychological findings. Gamma-frequency rhythms of discharge activity from thalamic and cortical neurons are facilitated by cholinergic arousal and resonate in networks of thalamocortical circuits, thereby transiently forming assemblies of coherent gamma oscillations under constraints of afferent sensory input and prefrontal attentional mechanisms. If perception is based on synchronisation of intrinsic gamma activity in the thalamocortical system, then sensory input to specific thalamic nuclei may merely play a constraining role. Hallucinations can be regarded as underconstrained perceptions that arise when the impact of sensory input on activation of thalamocortical circuits and synchronisation of thalamocortical gamma activity is reduced. In conditions that are accompanied by hallucinations, factors such as cortical hyperexcitability, cortical attentional mechanisms, hyperarousal, increased noise in specific thalamic nuclei, and random sensory input to specific thalamic nuclei may, to a varying degree, contribute to underconstrained activation of thalamocortical circuits. The reticular thalamic nucleus plays an important role in suppressing random activity of relay cells in specific thalamic nuclei, and its dysfunction may be implicated in the biological vulnerability to hallucinations in schizophrenia. Combined with general activation during cholinergic arousal, this leads to excessive disinhibition in specific thalamic nuclei, which may allow cortical attentional mechanisms to recruit thalamic relay cells into resonant assemblies of gamma oscillations, regardless of their actual sensory input, thereby producing an underconstrained perceptual experience.     

Nonlinear visuomotor transformations: locus and modularity

Participants in two experiments moved a mouse-like device to the right to move a cursor on a computer screen to a target position. The cursor was invisible during motion but reappeared at the end of each movement. The relationship between the amplitudes of the cursor movement and the mouse movement was exponential in Experiment 1 and logarithmic in Experiment 2 for two groups of participants, while it was linear for the control groups in both experiments. The results of both experiments indicate that participants adjusted well to the external transformation by developing an internal model that approximated the inverse of the external transformation. We introduce a method to determine the locus of the internal model. It indicates that the internal model works at a processing level that either preceded specification of movement amplitude, or had become part of movement amplitude specification. Limited awareness of the nonlinear mouse-cursor relationship and the fact that a working-memory task had little effect on performance suggest that the internal model is modular and not dependent on high-level cognitive processes.     

Nonlinear visuomotor transformations: Locus and modularity

Participants in two experiments moved a mouse-like device to the right to move a cursor on a computer screen to a target position. The cursor was invisible during motion but reappeared at the end of each movement. The relationship between the amplitudes of the cursor movement and the mouse movement was exponential in Experiment 1 and logarithmic in Experiment 2 for two groups of participants, while it was linear for the control groups in both experiments. The results of both experiments indicate that participants adjusted well to the external transformation by developing an internal model that approximated the inverse of the external transformation. We introduce a method to determine the locus of the internal model. It indicates that the internal model works at a processing level that either preceded specification of movement amplitude, or had become part of movement amplitude specification. Limited awareness of the nonlinear mouse–cursor relationship and the fact that a working-memory task had little effect on performance suggest that the internal model is modular and not dependent on high-level cognitive processes.     

Reliability and expected loss: A unifying principle

We provide a unified, theoretical basis on which measures of data reliability may be derived or evaluated, for both quantitative and qualitative data. This approach evaluates reliability as the proportional reduction in loss (PRL) that is attained in a sample by an optimal estimator. The resulting measure is between 0 and 1, linearly related to expected loss, and provides a direct way of contrasting the measured reliability in the sample with the least reliable and most reliable data-generating cases. The PRL measure is a generalization of many of the commonly-used reliability measures.We show how the quantitative measures from generalizability theory can be derived as PRL measures (including Cronbach's alpha and measures proposed by Winer). For categorical data, we develop a new measure for the general case in which each of N judges assigns a subject to one of K categories and show that it is equivalent to a measure proposed by Perreault and Leigh for the case where N is 2.Bruce Cooil is an Associate Professor of Statistics, and Roland T. Rust is a Professor and area head for Marketing. The authors thank three anonymous reviewers and an Associate Editor for their helpful comments and suggestions. This work was supported in part by the Dean's Fund for Faculty Research of the Owen Graduate School of Management, Vanderbilt University.     

Practice and retention: a unifying analysis.

What is the strength of a memory trace that has received various practices at times tj in the past? The strength accumulation equation proposes the following: strength = sigma tj-d, where the summation is over the practices of the trace. This equation predicts both the power law of practice and the power law of retention. This article reports the fits of the predictions of this equation to 5 experiments. Across these experiments, participants received as many as 240 trials of practice distributed over intervals as long as 400 days. The experiments also varied whether participants were just practicing retrieving an item or practicing applying a relatively complex rule. A model based on this equation successfully fit all the data when it was assumed that the passage of psychological time slowed after the experimental session. The strength accumulation equation was compared with other conceptions of the retention function and the relationship of the retention function to the practice function.     

Analogical insight: toward unifying categorization and analogy

The purpose of this paper is to present two kinds of analogical representational change, both occurring early in the analogy-making process, and then, using these two kinds of change, to present a model unifying one sort of analogy-making and categorization. The proposed unification rests on three key claims: (1) a certain type of rapid representational abstraction is crucial to making the relevant analogies (this is the first kind of representational change; a computer model is presented that demonstrates this kind of abstraction), (2) rapid abstractions are induced by retrieval across large psychological distances, and (3) both categorizations and analogies supply understandings of perceptual input via construing, which is a proposed type of categorization (this is the second kind of representational change). It is construing that finalizes the unification.     

Feeling and representing: Computational theory and the modularity of affect

In this paper I review some leading developments in the empirical theory of affect. I argue that (1) affect is a distinct perceptual representation governed system, and (2) that there are significant modular factors in affect. The paper concludes with the observation thatfeeler (affective perceptual system) may be a natural kind within cognitive science. The main purpose of the paper is to explore some hitherto unappreciated connections between the theory of affect and the computational theory of mind.     

Timing in cognition and EEG brain dynamics: discreteness versus continuity

This article provides an overview of recent developments in solving the timing problem (discreteness vs. continuity) in cognitive neuroscience. Both theoretical and empirical studies have been considered, with an emphasis on the framework of operational architectonics (OA) of brain functioning (Fingelkurts and Fingelkurts in Brain Mind 2:291-29, 2001; Neurosci Biobehav Rev 28:827-836, 2005). This framework explores the temporal structure of information flow and interarea interactions within the network of functional neuronal populations by examining topographic sharp transition processes in the scalp EEG, on the millisecond scale. We conclude, based on the OA framework, that brain functioning is best conceptualized in terms of continuity-discreteness unity which is also the characteristic property of cognition. At the end we emphasize where one might productively proceed for the future research.     

Context and coping: Toward a unifying conceptual framework

After offering a conceptual framework to unify the domains of context and coping, some conclusions are drawn about the underlying patterns of social climate and the characteristics of growth-promoting environments. New directions of research on the dynamics of the environmental system are described. The conceptual framework is used to exemplify ways to explore the stress and coping process in regard to such issues as stress and resource predictors of adaptation, stress prevention and resistance, and cross-situational influences. The foregoing material then highlights implications of a social ecological perspective for conducting conceptually informed evaluation research and changing and improving community settings. Finally, such conceptual problems as person-environment matching and the need to formulate unified perspectives of stressors and resources are discussed to identify promising ways to spark the maturation of community psychology.     

Children's use of landmarks: implications for modularity theory

Previous studies have shown that disoriented children use the geometric features of the environment to reorient, but the results have not consistently demonstrated whether children can combine such information with landmark information. Results indicating that they cannot suggest the existence of a geometric module for reorientation. However, results indicating that children can use geometric information in combination with landmark information challenge the modularity interpretation. An uncontrolled variable in the studies yielding conflicting results has been the size of the experimental space. In the present studies, which tested young children in spaces of two different sizes, the size of the space affected their ability to use available landmark information. In the small space, the children did not use the landmark to reorient, but in the large space they did. The ability of children to use landmarks in combination with geometric information raises important questions about the existence of an encapsulated geometric module.     

Brain and cognitive evolution: forms of modularity and functions of mind

Genetic and neurobiological research is reviewed as related to controversy over the extent to which neocortical organization and associated cognitive functions are genetically constrained or emerge through patterns of developmental experience. An evolutionary framework that accommodates genetic constraint and experiential modification of brain organization and cognitive function is then proposed. The authors argue that 4 forms of modularity and 3 forms of neural and cognitive plasticity define the relation between genetic constraint and the influence of developmental experience. For humans, the result is the ontogenetic emergence of functional modules in the domains of folk psychology, folk biology, and folk physics. The authors present a taxonomy of these modules and review associated research relating to brain and cognitive plasticity in these domains.     

Beyond faces and modularity: the power of an expertise framework

Studies of perceptual expertise typically ask whether the mechanisms underlying face recognition are domain specific or domain general. This debate has so dominated the literature that it has masked the more general usefulness of the expertise framework for studying the phenomenon of category specialization. Here we argue that the value of an expertise framework is not solely dependent on its relevance to face recognition. Beyond offering an alternative to domain-specific accounts of face specialization in terms of interactions between experience, task demands, and neural biases, expertise studies reveal principles of perceptual learning that apply to many different domains and forms of expertise. As such the expertise framework provides a unique window onto the functional plasticity of the mind and brain.     

The Cartesian frame of reference: A structure unifying the description of dyslexia

It is shown that six phenomena often associated with dyslexia may be attributed to the lack of a visual, Cartesian frame of reference. These phenomena are (1) reading errors due to letter reversal, inversion, or rotation, (2) form recognition of all classes of mono-oriented objects which is independent of the figure's egocentric orientation, (3) defective visual sequential scanning, resulting in confused letter and word order (4) poor visual balance performance, (5) the failure to acquire nonspatial ordering relations, including temporal relations and tenses, and (6) the characteristics intellectual profile of severely retarded readers, namely, PIQ/VIQ greater than 1, where PIQ is the performance IQ score and VIQ the verbal IQ score on the Wechsler Intelligence Scale for Children (WISC). The latter phenomenon is dependent on (2) and (5) above. A strategy for further research is outlined.     

Determinants of emotion attributions: A unifying view

Two cognitive approaches, introduced by Schachter and Singer (1962) and by Valins (1966), have dominated the experimental study of emotion attributions. However, subsequent results using these approaches have not appeared to be very consistent, and this view is not consistent with more physiologically oriented theory. Research significant in the development of theory from these approaches was examined. Inconsistent findings using the Schachter and Singer paradigm were attributed to the difficulty of producting completely ambiguous physiological cues. The existence of active search in determining the cause of arousal was established and found central to production of Valins's false feedback effect. Postulated mediation by self-persuasion was found to provide the best fit to the existing data. The generality of these studies was described in terms of a more comprehensive theory based on the finding that the relative ambiguity of situational and physiological cues seems to provide the fundamental control over the emotion attribution process. This synthesis eliminates the deficiencies in previous hypotheses by more completely encompassing potential cue combinations.     

Recognizing the un-real McCoy: priming and the modularity of face recognition

Fodor (1983) has proposed that face perception is carried out by an informationally encapsulated module, whose operation is unaffected by context or expectancies. We tested the modularity hypothesis by examining whether discriminations between normal and distorted versions of famous faces can be primed, either by the name of an associated person (semantic context) or by a valid cue as to the identity of the target face (expectancy). A preliminary experiment showed that, in the absence of priming, discriminations between normal and distorted versions of a face were unaffected by whether the target faces were familiar or not, confirming that these judgments tap perceptual, not postperceptual (semantic), coding processes. In Experiment 1, accuracy was significantly higher when target face pairs were preceded by related name primes, as compared with unrelated ones. In Experiment 2, reaction times were significantly faster for targets preceded by a valid identity cue than for targets preceded by an invalid one. Neither effect could be explained as a speed—accuracy tradeoff. These results fail to support Fodor’s conjecture that face processing is encapsulated.     

Recognizing words and pictures in sentence contexts: a test of lexical modularity

Words or pictures completed sentence fragments to form coherent or incoherent sentences. Subjects made lexical decisions about words and object decisions about pictures. Modality was blocked in Experiment 1 and mixed in Experiment 2. In both experiments there were similar effects of context for words and pictures, contrary to the hypothesis that lexical priming produces the sentence context effect. Mixed conditions produced longer response latencies than blocked conditions but did not interact with the context effect. The finding of no interaction between the effect of context and the mixed-blocked manipulation, supports a version of lexical modularity in which context effects arise as a function of post-access integration processing.