Consciousness and the Prefrontal Parietal Network: Insights from Attention, Working Memory, and Chunking

Abstract

Consciousness has of late become a “hot topic” in neuroscience. Empirical work has centered on identifying potential neural correlates of consciousness (NCCs), with a converging view that the prefrontal parietal network (PPN) is closely associated with this process. Theoretical work has primarily sought to explain how informational properties of this cortical network could account for phenomenal properties of consciousness. However, both empirical and theoretical research has given less focus to the psychological features that may account for the NCCs. The PPN has also been heavily linked with cognitive processes, such as attention. We describe how this literature is under-appreciated in consciousness science, in part due to the increasingly entrenched assumption of a strong dissociation between attention and consciousness. We argue instead that there is more common ground between attention and consciousness than is usually emphasized: although objects can under certain circumstances be attended to in the absence of conscious access, attention as a content selection and boosting mechanism is an important and necessary aspect of consciousness. Like attention, working memory and executive control involve the interlinking of multiple mental objects and have also been closely associated with the PPN. We propose that this set of cognitive functions, in concert with attention, make up the core psychological components of consciousness. One related process, chunking, exploits logical or mnemonic redundancies in a dataset so that it can be recoded and a given task optimized. Chunking has been shown to activate PPN particularly robustly, even compared with other cognitively demanding tasks, such as working memory or mental arithmetic. It is therefore possible that chunking, as a tool to detect useful patterns within an integrated set of intensely processed (attended) information, has a central role to play in consciousness. Following on from this, we suggest that a key evolutionary purpose of consciousness may be to provide innovative solutions to complex or novel problems.

A higher-order theory of emotional consciousness

“…Included are theories that emphasize attention and working memory (47,55,57,59,(103)(104)(105)(106)(107)(108)(109), processing by a global workspace (56,110,111), or the interpretation of experience (112). A common thread that runs through various cognitive theories is that processing beyond the sensory cortex is required for conscious experience.…”

Cortical networks involved in visual awareness independent of visual attention

“…A number of elegant paradigms have been designed for this purpose, with the aim of making the stimulus as similar as possible in the two conditions (1,2), such that any neural differences that emerge are more reasonably attributed to a difference in awareness than to a difference in the stimuli themselves. Using this approach, studies have pointed to a frontoparietal network, including the dorsolateral prefrontal cortex, the middle and inferior frontal gyri, the intraparietal sulcus, the superior parietal lobule, and a number of regions within the temporoparietal junction (TPJ) (3)(4)(5)(6)(7)(8)(9), although some questions remain regarding the specific role of each of these regions (9)(10)(11).…”

Synaesthesia quotient: operationalising an individual index of phenotypic expressivity of developmental synaesthesia

“…It has been suggested that large-scale interactions between high-level (executive) and low-level (perceptual) areas are crucial for rendering perception reportable (Rees et al 2002;Lamme 2003;Dehaene et al 2006). As is shown in an EEG study, access awareness was selectively correlated with increased gamma-coupling between anterior and posterior brain areas (Melloni et al 2007; see also Bor and Seth 2012). Moreover, a MEG-study showed that, whether attended or not, consciously seen stimuli induced increased mid-gamma activity (54-64 Hz) 240-500 ms over the contralateral visual cortex, whereas attended versus unattended stimuli caused a significant increase in high-gamma range (76-90 Hz) with a slightly delayed latency (350-500 ms) and was uniquely modulated by attention (not by conscious experience).…”