Brain-based versus external memory stores: influencing factors and underlying neural correlates

Technological advancements provide people with more opportunity to rely on external resources to support cognitive processes. These associated processes are defined as cognitive offloading (Risko & Gilbert, 2016). The current thesis aims to explore the psychological processes and neural mechanism of cognitive offloading. In Experiment 1, we developed an ‘optimal reminder’ task by calculating whether people were biased towards using reminders or their own memory, compared with an optimal strategy. If participants were biased, the second purpose of Experiment 1 was to assess whether such bias could be reduced through metacognitive advice. Results revealed people were biased towards setting reminders, and the bias was eliminated by metacognitive advice. Experiment 2 used the optimal reminder task to evaluate the effect of ageing on cognitive offloading. This showed that older people set more reminders than younger adults, but were less biased towards setting reminders when the impaired memory performance of older people was taken into account. Experiment 3 investigated the effects of three factors: delay length, metacognitive judgement, and clock revealability, on cognitive offloading in a time-based task (e.g. remembering to press a specific button after 10 seconds). We found participants’ use of reminders was based on both the characteristics of the task (i.e., delay and clock revealability) and metacognitive judgements. Experiment 4 used fMRI to evaluate whether an instruction to offload information to an external reminder triggered different brain activity to an instruction to forget or remember. Results showed that brain activity associated with an offload cue was similar, but not identical, to brain activity associated with a forget cue. We conclude by suggesting possible applications of the results to finding methods for improving intention offloading and avoiding memory failures

An investigation of the saving-enhanced memory effect: The role of test order and list saving

Saving information onto external resources can improve memory for subsequent information—a phenomenon known as the saving-enhanced memory effect. This article reports two preregistered online experiments investigating (A) whether this effect holds when to-be-remembered information is presented before the saved information and (B) whether people choose the most advantageous strategy when given free choice of which information to save. Participants studied two lists of words; test order and whether and which list was saved (and re-presented again later) were manipulated. The saving-enhanced memory effect was only found when the first list (List A) was saved and tested after the second list (List B). When free to choose which list to save, participants preferred to save List A, but only when it was recalled after List B—that is, when it benefited memory. These findings suggest boundary conditions for the saving-enhanced memory effect and that people offload the most profitable information

Optimal cognitive offloading: Increased reminder usage but reduced proreminder bias in older adults

Research into prospective memory suggests that older adults may face particular difficulties remembering delayed intentions. One way to mitigate these difficulties is by using external reminders but relatively little is known about age-related differences in such cognitive offloading strategies. We examined younger and older adults' (N = 88) performance on a memory task where they chose between remembering delayed intentions with internal memory (earning maximum reward per item) or external reminders (earning a reduced reward). This allowed us to distinguish (a) the absolute number of reminders used versus (b) the proreminder or antireminder bias, compared with each individual's optimal strategy. Older adults used more reminders overall, as might be expected, because they also had poorer memory performance. However, when compared against the optimal strategy weighing the costs versus benefits of reminders, it was only the younger adults who had a proreminder bias. Younger adults overestimated the benefit of reminders, whereas older adults underestimated it. Therefore, even when aging is associated with increased use of external memory aids overall, it can also be associated with reduced preference for external memory support, relative to the objective need for such support. This age-related difference may be driven at least in part by metacognitive processes, suggesting that metacognitive interventions could lead to improved use of cognitive tools. (PsycInfo Database Record (c) 2023 APA, all rights reserved)

Outsourcing Memory to External Tools: A Review of 'Intention Offloading'

How do we remember delayed intentions? Three decades of research into prospective memory have provided insight into the cognitive and neural mechanisms involved in this form of memory. However, we depend on more than just our brains to remember intentions. We also use external props and tools such as calendars and diaries, strategically placed objects, and technologies such as smartphone alerts. This is known as 'intention offloading'. Despite the progress in our understanding of brain-based prospective memory, we know much less about the role of intention offloading in individuals' ability to fulfil delayed intentions. Here, we review recent research into intention offloading, with a particular focus on how individuals decide between storing intentions in internal memory versus external reminders. We also review studies investigating how intention offloading changes across the lifespan and how it relates to underlying brain mechanisms. We conclude that intention offloading is highly effective, experimentally tractable, and guided by metacognitive processes. Individuals have systematic biases in their offloading strategies that are stable over time. Evidence also suggests that individual differences and developmental changes in offloading strategies are driven at least in part by metacognitive processes. Therefore, metacognitive interventions could play an important role in promoting individuals' adaptive use of cognitive tools

Rapid and sensitive insulated isothermal PCR for point-of-need feline leukaemia virus detection

Objectives: Feline leukaemia virus (FeLV), a gamma retrovirus, causes diseases of the feline haematopoietic system that are invariably fatal. Rapid and accurate testing at the point-of-need (PON) supports prevention of virus spread and management of clinical disease. This study evaluated the performance of an insulated isothermal PCR (iiPCR) that detects proviral DNA, and a reverse transcription (RT)-iiPCR that detects both viral RNA and proviral DNA, for FeLV detection at the PON. Methods: Mycoplasma haemofelis, feline coronavirus, feline herpesvirus, feline calicivirus and feline immunodeficiency virus were used to test analytical specificity. In vitro transcribed RNA, artificial plasmid, FeLV strain American Type Culture Collection VR-719 and a clinical FeLV isolate were used in the analytical sensitivity assays. A retrospective study including 116 clinical plasma and serum samples that had been tested with virus isolation, real-time PCR and ELISA, and a prospective study including 150 clinical plasma and serum samples were implemented to evaluate the clinical performances of the iiPCR-based methods for FeLV detection. Results: Ninety-five percent assay limit of detection was calculated to be 16 RNA and five DNA copies for the RT-iiPCR, and six DNA copies for the iiPCR. Both reactions had analytical sensitivity comparable to a reference real-time PCR (qPCR) and did not detect five non-target feline pathogens. The clinical performance of the RT-iiPCR and iiPCR had 98.82% agreement (kappa[κ] = 0.97) and 100% agreement (κ = 1.0), respectively, with the qPCR (n = 85). The agreement between an automatic nucleic extraction/RT-iiPCR system and virus isolation to detect FeLV in plasma or serum was 95.69% (κ = 0.95) and 98.67% (κ = 0.85) in a retrospective (n = 116) and a prospective (n = 150) study, respectively. Conclusions and relevance: These results suggested that both RT-iiPCR and iiPCR assays can serve as reliable tools for PON FeLV detection