Growing evidence for separate neural mechanisms for attention and consciousness

Abstract

Our conscious experience of the world seems to go in lockstep with our attentional focus: we tend to see, hear, taste and feel what we attend to, and vice versa. This tight coupling between attention and consciousness has given rise to the idea that these two phenomena are indivisible. In the late 1950s, the honoree of this special issue, Charles Eriksen, was among a small group of early pioneers that sought to investigate whether a transient increase in overall level of attention (alertness) in response to a noxious stimulus can be decoupled from conscious perception using experimental techniques. Recent years saw a similar debate regarding whether attention and consciousness are two dissociable processes. Initial evidence that attention and consciousness are two separate processes primarily rested on behavioral data. However, the past couple of years witnessed an explosion of studies aimed at testing this conjecture using neuroscientific techniques. Here we provide an overview of these and related empirical studies on the distinction between the neuronal correlates of attention and consciousness, and detail how advancements in theory and technology can bring about a more detailed understanding of the two. We argue that the most promising approach will combine ever evolving neurophysiological and interventionist tools with quantitative, empirically testable theories of consciousness that are grounded in a mathematically formalized understanding of phenomenology.

Vicarious attention, degrees of enhancement, and the contents of consciousness

“…On the other hand, there is also an overwhelming amount of empirical and theoretical support for the idea that selective attention and phenomenal consciousness are rather independent of each other Maier & Tsuchiya, 2021;Tallon-Baudry, 2012;Tallon-Baudry et al, 2018;Van Boxtel et al, 2010b). I will now provide an overview of this evidence.…”

“…Behavioral studies suggesting a dissociation between the contents of phenomenal consciousness and selective attention have been further supported by neuroscientific studies relying on diverse techniques. fMRI, EEG, magnetoencephalography (MEG), and single-unit recording evince different neural correlates for selective attention and conscious perception (Maier & Tsuchiya, 2021;Van Boxtel et al, 2010b). Moreover, as pointed out above, findings previously taken to reveal common neural correlates for attention and consciousness have recently been re-assessed in the light of further empirical findings, methodological refinements, and more finely-grained conceptual distinctions (Tallon-Baudry, 2012;Tallon-Baudry et al, 2018).…”

“…Regarding attention, here I adopt a characterization that is fairly standard amongst empirical researchers. I take attention to be a process involving the selection of a subset of the available sensory information for preferential processing, a mental focus in a particular aspect of information, and the prioritization of some parts of the information that is available at any given moment (Carrasco, 2011;Desimone & Duncan, 1995;Posner, 1980;Cohen et al, 2012;Maier & Tsuchiya, 2021;Naghavi & Nyberg, 2005;Nani et al, 2019; see also Pitts et al, 2018). Nevertheless, we must note that this characterization only pins down a specific kind of attention, namely selective attention.…”

“…It also comes from studies suggesting that attention has effects similar to increasing some perceptual dimensions, such as brightness or contrast (Carrasco & Barbot, 2019;Fazekas & Nanay, 2021; also see the studies on perceptual adaptation cited in section 3.1). Furthermore, the framework can accommodate the further finding that the response increases associated with consciousness are significantly greater than those associated with attention (Kouider et al, 2016), a finding that is sometimes thought to evince a dissociation between attention and consciousness (Maier & Tsuchiya, 2021).…”

Representational ‘touch’ and modulatory ‘retouch’—two necessary neurobiological processes in thalamocortical interaction for conscious experience

“…Importantly, there are many data and a growing consensus that mechanisms of attention and conscious experience are autonomous, although typically interacting ( Wyart and Tallon-Baudry 2008 ; Bachmann 2011 ; Webb et al. 2016 ; Maier and Tsuchiya 2020 ). While in typical cases attention increases veridicality and subjective vividness of target stimuli (supposedly recruiting the consciousness mechanism for facilitative modulation), selective attention can be driven also unconsciously (e.g.…”