The exploration of meditation in the neuroscience of attention and consciousness

Many recent behavioral and neuroscientific studies have revealed the importance of investigating meditation states and traits to achieve an increased understanding of cognitive and affective neuroplasticity, attention and self-awareness, as well as for their increasingly recognized clinical relevance. The investigation of states and traits related to meditation has especially pronounced implications for the neuroscience of attention, consciousness, self-awareness, empathy and theory of mind. In this article we present the main features of meditation-based mental training and characterize the current scientific approach to meditation states and traits with special reference to attention and consciousness, in light of the articles contributed to this issue.     

An effect of spatial-temporal association of response codes: understanding the cognitive representations of time

The present study addresses the question of how such an abstract concept as time is represented by our cognitive system. Specifically, the aim was to assess whether temporal information is cognitively represented through left-to-right spatial coordinates, as already shown for other ordered sequences (e.g., numbers). In Experiment 1, the task-relevant information was the temporal duration of a cross. RTs were shorter when short and long durations had to be responded to with left and right hands, respectively, than with the opposite stimulus-response mapping. The possible explanation that the foreperiod effect (i.e., shorter RTs for longer durations) is greater with right than with left hand responses is discarded by results of Experiment 2, in which right and left hand responses alternated block-wise in a variable foreperiod paradigm. Other explanations concerning manual or hemispheric asymmetries may be excluded based on the results of control experiments, which show that the compatibility effect between response side and cross duration occurs for accuracy when responses are given with crossed hands (Experiment 3), and for RTs when responses are given within one hand (Experiment 4). This pattern suggests that elapsing time, similarly to other ordered information, is represented in some circumstances through an internal spatial reference frame, in a way that may influence motor performance. Finally, in Experiment 5, the temporal duration was parametrically varied using different values for each response category (i.e., 3 short and 3 long durations). The compatibility effect between hand and duration was replicated, but followed a rectangular function of the duration. The shape of this function is discussed in relation to the specific task demands.     

Impaired self-reflection in psychiatric disorders among adults: A proposal for the existence of a network of semi independent functions

Self-reflection plays a key role in healthy human adaptation. Self-reflection might involve different capacities which may be impaired to different degrees relatively independently of one another. Variation in abilities for different forms of self-reflection are commonly seen as key aspects of many adult mental disorders. Yet little has been written about whether there are different kinds of deficits in self-reflection found in mental illness, how those deficits should be distinguished from one another and how to characterize the extent to which they are interrelated. We review clinical and experimental literature and suggest four different forms of deficits in self-reflection: (a) sense of ownership of one’s own thoughts and actions, (b) emotional awareness, (c) distinction between fantasy and reality and (d) the integration of a range of different views of oneself and others. We propose how these different impairments in self-reflection are linked with one another.     

Developmental dissociations of preparation over time: deconstructing the variable foreperiod phenomena

In a variable foreperiod (FP) paradigm, reaction times (RTs) decrease as a function of FP on trial n (FP effect) but increase with FP on trial n - 1 (sequential effects). These phenomena have traditionally been ascribed to different strategic preparation processes. According to an alternative explanation, common conditioning laws underlie both effects. The present study aims to disentangle these opposite views using a developmental perspective. In Experiment 1A, 4- to 11-year-old children and a control group of adults performed a simple RT task with variable FPs (1, 3, and 5 s). Furthermore, 12 4- to 5-year-old children were retested after 14 months (Experiment 1B). In Experiment 2, a narrower pool of participants (4, 5, and 6 years old) performed a variable FP paradigm with different FPs (1, 2, and 3 s). The results consistently suggest different ontogenetic time courses for the two effects: The sequential effects are already present in the youngest group (4-5 years old), whereas the FP effect appears gradually some years later. These findings are not fully compatible with previous views. A dual-process account is proposed to explain the data.     

The effects of choice-making on the problem behaviors of high school students with intellectual disabilities

This investigation was conducted in an effort to systematically extend the emerging data base having to do with choice-making opportunities and the behavior of students with disabilities. In particular, the current analyses examined the effects of choice-making on the problem behavior and task engagement of three high school students with intellectual disabilities as the students performed domestic and vocational activities. Multiple baseline and reversal designs demonstrated that the choice conditions reduced problem behaviors and increased task engagement for all participants. Data having to do with student affect and task productivity were less consistent. The findings on the relationship between choice making and problem behavior replicate and extend a growing literature on the desirable effects of choice-making for individuals with disabilities. The results are discussed in terms of recent developments in behavioral support, as well as the need for ongoing conceptual and applied research.     

The abstract variable-binding calculus

Theabstract variable binding calculus (VB-calculus) provides a formal frame-work encompassing such diverse variable-binding phenomena as lambda abstraction, Riemann integration, existential and universal quantification (in both classical and nonclassical logic), and various notions of generalized quantification that have been studied in abstract model theory. All axioms of the VB-calculus are in the form of equations, but like the lambda calculus it is not a true equational theory since substitution of terms for variables is restricted. A similar problem with the standard formalism of the first-order predicate logic led to the development of the theory of cylindric and polyadic Boolean algebras. We take the same course here and introduce the variety of polyadic VB-algebras as a pure equational form of the VB-calculus. In one of the main results of the paper we show that every locally finite polyadic VB-algebra of infinite dimension is isomorphic to a functional polyadic VB-algebra that is obtained from a model of the VB-calculus by a natural coordinatization process. This theorem is a generalization of the functional representation theorem for polyadic Boolean algebras given by P. Halmos. As an application of this theorem we present a strong completeness theorem for the VB-calculus. More precisely, we prove that, for every VB-theory T that is obtained by adjoining new equations to the axioms of the VB-calculus, there exists a model D such that _T s=t iff _D s=t. This result specializes to a completeness theorem for a number of familiar systems that can be formalized as VB-calculi. For example, the lambda calculus, the classical first-order predicate calculus, the theory of the generalized quantifierexists uncountably many and a fragment of Riemann integration.The work of the first author was supported in part by National Science Foundation Grant #DMS 8805870.     

On the Axiomatisation of Elgesem's Logic of Agency and Ability

In this paper we show that the Hilbert system of agency and ability presented by Dag Elgesem is incomplete with respect to the intended semantics. We argue that completeness result may be easily regained. Finally, we shortly discuss some issues related to the philosophical intuition behind his approach. This is done by examining Elgesem's modal logic of agency and ability using semantics with different flavours.     

Evidence for the substantia nigra pars compacta as an essential component of a memory system independent of the hippocampal memory system

The aim of the present study was to test if the nigrostriatal pathway is an essential component for a water maze cued task learning and if it works independently of the hippocampal memory system. This hypothesis was tested using an animal model of Parkinson's disease in which male Wistar rats were lesioned in the substantia nigra pars compacta (SNc) by the intranigral infusion of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), thus causing a partial depletion of striatal dopamine. SNc-lesioned and sham-operated animals were implanted bilaterally with guide cannulae above the dorsal hippocampus in order to be tested after the administration of 0.4 microl 2% lidocaine or saline into this structure. The animals were tested in a spatial or in a cued version of the water maze, memory tasks previously reported to model hippocampal-dependent spatial/relational and striatal-dependent S-R learning, respectively. Hippocampal inactivation, but not SNc lesion, impaired learning and memory in the spatial version of the water maze. An opposite situation was observed with the cued version. No significant interaction was observed between the SNc lesion and hippocampal inactivation conditions affecting scores in the spatial or in the cued version of the water maze. These results suggest that the nigrostriatal pathway is an essential part of the memory system that processes S-R learning and that it works independently of the hippocampal memory system that processes spatial/relational memories.     

Social cognition and real-life functioning in patient samples with 22q11.2 deletion syndrome with or without psychosis,compared to a large sample of patients with schizophrenia only and healthy controls

Patients with the 22q11.2 deletion syndrome (DS) show an increased risk of developing a psychotic illness lifetime. 22q11.2DS may represent a reliable model for studying the neurobiological underpinnings of schizophrenia. The study of social inference abilities in a genetic condition at high risk for psychosis, like 22q11.2DS, may shed light on the relationships between neurocognitive processes and patients' daily general functioning. The study sample consisted of 1736 participants, divided into four groups: 22q11.2DS patients with diagnosis of psychotic disorder (DEL SCZ, N = 20); 22q11.2DS subjects with no diagnosis of psychosis (DEL, N = 43); patients diagnosed with schizophrenia without 22q11.2DS (SCZ, N = 893); and healthy controls (HC, N = 780). Social cognition was assessed through The Awareness of Social Inference Test (TASIT) and general functioning through the Specific Levels of Functioning (SLoF) scale. We analysed data through regression analysis. The SCZ and DEL groups had similar levels of global functioning; they both had significantly lower SLoF Total scores than HC (p < .001); the DEL SCZ group showed significantly lower scores compared to the other groups (SCZ, p = .004; DEL, p = .003; HC, p < .001). A significant deficit in social cognition was observed in the three clinical groups. In the DEL SCZ and SCZ groups, TASIT scores significantly predicted global functioning (p < .05). Our findings of social cognition deficit in psychosis-prone patients point to the possible future adoption of rehabilitation programmes, like Social Skills Training and Cognitive Remediation, during premorbid stages of psychosis.