The minimal self hypothesis

For millennia self has been conjectured to be necessary for consciousness. But scant empirical evidence has been adduced to support this hypothesis. Inconsistent explications of “self” and failure to design apt experiments have impeded progress. Advocates of phenomenological psychiatry, however, have helped explicate “self,” and employed it to explain some psychopathological symptoms. In those studies, “self” is understood in a minimalist sense, sheer “for-me-ness.” Unfortunately, explication of the “minimal self” (MS) has relied on conceptual analysis, and applications to psychopathology have been hermeneutic, allowing for many degrees of interpretive latitude. The result is that MS’s current scientific status is analogous to that of the “atom,” at the time when “atom” was just beginning to undergo transformation from a philosophical to a scientific concept. Fortunately, there is now an opportunity to promote a similar transformation for “MS.” Discovery of the brain’s Default Mode Network (DMN) opened the door to neuroimaging investigations of self. Taking the DMN and other forms of intrinsic activity as a starting point, an empirical foothold can be established, one that spurs experimental research and that enables extension of research into multiple phenomena. New experimental protocols that posit “MS” can help explain phenomena hitherto not thought to be related to self, thereby hastening development of a mature science of self. In particular, targeting phenomena wherein consciousness is lost and recovered, as in some cases of Unresponsive Wakefulness Syndrome (UWS), allow for design of neuroimaging probes that enable detection of MS during non-conscious states. These probes, as well as other experimental protocols applied to NREM Sleep, General Anesthesia (GA), and the waking state, provide some evidence to suggest that not only can self and consciousness dissociate, MS might be a necessary precondition for conscious experience. Finally, these findings have implications for the science of consciousness: it has been suggested that “levels of consciousness” (LoC) is not a legitimate concept for the science of consciousness. But because we have the conceptual and methodological tools with which to refine investigations of MS, we have the means to identify a possible foundation—a bifurcation point—for consciousness, as well as the means by which to measure degrees of distance from that foundation. These neuroimaging investigations of MS position us to better assess whether LoC has a role to play in a mature science of consciousness.     

Children’s Memory for Temporal Information: The Roles of Temporal Language and Executive Function

Abstract

The ability to recall the temporal order of events develops much more slowly than the ability to recall facts about events. To explore what processes facilitate memory for temporal information, we tested 3- to 6-year-old children (N?=?40) for immediate memory of the temporal order of events from a storybook, using a visual timeline task and a yes/no recognition task. In addition, children completed tasks assessing their understanding of before and after and the executive functions of inhibition using the Day/Night Stroop task and cognitive shifting using the Dimensional Change Card Sort (DCCS) task. Older children (Mage?=?69.25?months) outperformed younger children (Mage?=?52.35?months) on all measures; however, the only significant predictor of memory for the temporal ordering of events was cognitive shifting. The findings suggest that the difficulty in memory for temporal information is related to development of a general cognitive ability, as indexed by the DCCS, rather than specific temporal abilities.     

The role of attention level in the attentional boost effect

ABSTRACT

Previous studies reported a memory facilitation effect in which increased attention to one task facilitates the memory performance on another. Here we examined the characteristics of this “attentional boost effect” (ABE), and demonstrated how attention level during memory encoding influences the ABE strength by changing the occurring frequency of the attention-engaging target signal relative to the non-attention-engaging distractor signal (Experiment 1), and the physical salience of colour of the target signal (Experiment 2). The results indicated stronger ABE in conditions with a low ratio of target signal trials and with a salient target signal. Experiment 3 examined the role of spatial attention, which sought to measure how the distance between the target signal and the to-be-encoded item would influence the ABE strength. The results showed that the ABE strength was not influenced by the distance between the two. Overall, these findings suggest ABE may be mainly based on temporal attention.     

Memory for temporal order in novel sequential action

ABSTRACT

Order is critical for many daily activities. Developmental research has shown that memory for order in action is the least prioritised in a processing hierarchy, and is sensitive to deviant input. The current research investigated these aspects of sequence learning are also present in adults. Participants learned a novel sequence across several exemplars with either easy- or difficult-to-categorize items, which either did or did not involve a deviant order on one exemplar, and were later asked to recall the sequence. Memory for individual sub-actions and order was stronger in the easy conditions, and the deviant order significantly deteriorated ordered recall in the difficult condition only. These findings support the theorised processing hierarchy, with the presence of a deviant order having a larger effect on memory when the load at the earlier item stage is increased. These results have implications for theories of working memory and learning in real-world contexts.     

Modeling the emergence of informational content by adaptive networks for temporal factorisation and criterial causation

Propagated activation of neurons through their network is an important process in the brain. Another crucial part of neural processing concerns adaptation over time of characteristics of this network such as connection strengths or excitability thresholds. This adaptation can be slow, as in learning from a multiple experiences, or it can be fast, as in memory formation. These adaptive network characteristics can be considered informational criteria for activation of a neuron. This then is viewed as a form of emergent information formation. Activation of neurons is determined by such information via a process termed criterial causation. In the current paper, the relationship of criterial causation with the principle of temporal factorisation for the dynamics of the world in general is explored. Temporal factorisation describes how the world represents information about its past in its present state, which then in turn determines the world’s future. In the paper, it is shown how these processes are analysed in more detail and modeled by (adaptive) network models.