Both the global workspace theory and Block’s distinction between phenomenal and access consciousness, are central in the current debates about consciousness and the neural correlates of consciousness. In this article, a unifying global workspace model for phenomenal and access consciousness is proposed. In the model, recurrent neural interactions take place in distinct yet interacting access and phenomenal brain loops. The effectiveness of feedback signaling onto sensory cortical maps is emphasized for the neural correlates of phenomenal consciousness. Two forms of top-down (...) attention, attention for perception and attention for access, play differential roles for phenomenal and access consciousness. The model is implemented in a neural network form, with the simulation of single and multiple visual object processing, and of the attentional blink. (shrink)
Mindfulness can be understood as the mental ability to focus on the direct and immediate perception or monitoring of the present moment with a state of open and nonjudgmental awareness. Descriptions of mindfulness and methods for cultivating it originated in eastern spiritual traditions. These suggest that mindfulness can be developed through meditation practice to increase positive qualities such as awareness, insight, wisdom, and compassion. In this article we focus on the relationships between mindfulness, with associated meditation practices, and the cognitive (...) neuroscience of attention and awareness. Mindful awareness is related to distributed attention, phenomenal consciousness, and momentary self-awareness, as characterized by recent findings in cognitive psychology and neuroscience as well as in influential consciousness models. Finally, we outline an integrated neurocognitive model of mindfulness, attention, and awareness, with a key role of prefrontal cortex. (shrink)
In recent decades, psychological research on the effects of mindfulness-based interventions has greatly developed and demonstrated a range of beneficial outcomes in a variety of populations and contexts. Yet, the question of how to foster subjective well-being and happiness remains open. Here, we assessed the effectiveness of an integrated mental training program The Art of Happiness on psychological well-being in a general population. The mental training program was designed to help practitioners develop new ways to nurture their own happiness. This (...) was achieved by seven modules aimed at cultivating positive cognition strategies and behaviors using both formal and informal practices. The program was conducted over a period of 9 months, also comprising two retreats, one in the middle and one at the end of the course. By using a set of established psychometric tools, we assessed the effects of such a mental training program on several psychological well-being dimensions, taking into account both the longitudinal effects of the course and the short-term effects arising from the intensive retreat experiences. The results showed that several psychological well-being measures gradually increased within participants from the beginning to the end of the course. This was especially true for life satisfaction, self-awareness, and emotional regulation, highlighting both short-term and longitudinal effects of the program. In conclusion, these findings suggest the potential of the mental training program, such as The Art of Happiness, for psychological well-being. (shrink)
Conceptual knowledge is acquired through recurrent experiences, by extracting statistical regularities at different levels of granularity. At a fine level, patterns of feature co-occurrence are categorized into objects. At a coarser level, patterns of concept co-occurrence are categorized into contexts. We present and test CONCAT, a connectionist model that simultaneously learns to categorize objects and contexts. The model contains two hierarchically organized CALM modules (Murre, Phaf, & Wolters, 1992). The first module, the Object Module, forms object representations based on co-occurrences (...) between features. These representations are used as input for the second module, the Context Module, which categorizes contexts based on object co-occurrences. Feedback connections from the Context Module to the Object Module send activation from the active context to those objects that frequently occur within this context. We demonstrate that context feedback contributes to the successful categorization of objects, especially when bottom-up feature information is degraded or ambiguous. (shrink)
The distinction between phenomenal and access consciousness is central to debates about consciousness and its neural correlates. However, this distinction has often been limited to the domain of perceptual experiences. On the basis of dream phenomenology and neuroscientific findings this paper suggests a theoretical framework which extends this distinction to dreaming, also in terms of plausible neural correlates. In this framework, phenomenal consciousness is involved in both waking perception and dreaming, whereas access consciousness is weakened, but not fully eliminated, during (...) dreaming. However, access consciousness is more active during lucid dreaming. The proposed framework accounts for different aspects of dream phenomenology, including levels of integration of perceptual, cognitive and affective features in dreams, bizarreness, dream amnesia and the occurrence of meta-awareness and accessibility in lucid dreaming. Self-related experiences and their neural substrates are suggested to be differently involved in waking cognition and dreaming. Further, phenomenal consciousness during both waking and dream experiences involve widespread recurrent interactions and convergence-divergence zones in the thalamo-cortico-limbic system, activated before conscious access in global workspace areas. Finally, we discuss the relationships of the proposed framework with other neurocognitive theories and models of consciousness and major theories of dreaming, and propose novel experimental predictions. (shrink)
Phillips & Silverstein emphasize the gain-control properties of NMDA synapses in cognitive coordination. We endorse their view and suggest that NMDA synapses play a crucial role in biased attentional competition and (visual) working memory. Our simulations show that NMDA synapses can control the storage rate of visual objects. We discuss specific predictions of our model about cognitive effects of NMDA-antagonists and schizophrenia.
Tsuda's article suggests several plausible concepts of neurodynamic representation and processing, with a thoughtful discussion of their neurobiological grounding and formal properties. However, Tsuda's theory leads to a holistic view of brain functions and to the controversial conclusion that the “binding problem” is a pseudo-problem. By contrast, we stress the role of chaotic patterns in solving the binding problem, in terms of flexible temporal coding of visual scenes through graded and intermittent synchrony.
The tension between focusing on species similarities versus species differences (phylogenetic versus adaptationist approaches) recurs in discussions about the nature of neural connectivity and organization following brain expansion. Whereas Striedter suggests a primary role for response inhibition, other possibilities include dense recurrent connectivity loops. Computer simulations and brain imaging technologies are crucial in better understanding actual neuronal connectivity patterns.
We note two important problems in the Theory of Event Coding. First, because the representational format of features and events is unspecified, the theory is difficult to test. Second, the theory lacks a mechanism for the integration of features into an event code when the features are shared by different events. Possible ways of solving these problems are suggested.
Barlow's concept of the exploitation of environmental statistical regularities may be more plausibly related to brain mechanisms than Shepard's notion of internalisation. In our view, Barlow endorses a bottom-up approach to neural coding and processing, whereas we suggest that feedback interactions in the visual system, as well as chaotic correlation dynamics in the brain, are crucial in exploiting and assimilating environmental regularities. We also discuss the “conceptual tension” between Shepard's ideas of law internalisation and evolutionary adaptation. [Barlow; Shepard].