It is proposed that attention to an object requires the simultaneous activity of three brain regions that are interconnected by a triangular circuit. The regions are the cortical site of attentional expression, the thalamic enhancement structure, and the prefrontal area of control. It is also proposed that awareness of an object requires the additional component of attention directed to a representation of the self. The expression of attention to a self-representation may involve activations of cortical sites corresponding to the body (...) landscape and/or verbal-based memories of autobiographical episodes. As in the case of attention to objects, attention to the self is presumed to involve a triangular circuit. The proposed triangular circuit of attention is shown to be generally consistent with current knowledge of brain structures and with data from a broad range of experiments concerned with the functions of neurons in these structures. (shrink)

The ongoing steady nature of consciousness in everyday life implies that the underlying neural activity possesses a high level of stability. The prolonged cognitive events of sustained attention, imagery, and working memory also imply high stability of underlying neural activity. This paper proposes that stabilization of neural activity is produced by apical dendrite activity in pyramidal neurons within recurrent corticothalamic circuits, and proposes that the wave activities of apical dendrites that stabilize ongoing activity constitute the subjective impressions of an attended (...) object and the entire sensory background. The cortical minicolumn, as the functional unit of the cortex, is separated into an axis consisting of layer 5 pyramidal neurons and a surrounding shell consisting of layer 2/3 pyramidal neurons. It is proposed that apical dendrites of the axis generate sensory impressions, and basal dendrites of the shell process the brief-lasting input–output identifications of objects that give rise to ideas. (shrink)

Replies are given to the commentaries of the seven cognitive science experts. Additional circuit diagrams clarify thalamic operations in attention and basal ganglia operations by which motivation affects attention. Selection-by-suppression and negative priming are accounted for within frontal control areas. Confusions between the terms awareness and consciousness persist, owing to the powerful habit of using awareness as a synonym for consciousness. Leaving consciousness as an umbrella term to denote many loosely-defined aspects of experience, the term awareness denotes the aspect of (...) experience in which attention is directed to bodily sensations, thereby involving the self in ongoing experience. The responses to the commentaries are organized under three main headings: anatomical properties of the triangular circuit of attention; functions of the triangular circuit in attention; and relations of attention to awareness and self-awareness. (shrink)

PRECIS OF: LaBerge, D. "Attention, Awareness, and the Triangular Circuit". Consciousness and Cognition, 6, 149-181.