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Decades of neuropsychological and neuroimaging evidence have implicated the lateral parietal cortex (LPC) in a myriad of cognitive domains, generating numerous influential theoretical models. However, these theories fail to explain why distinct cognitive activities appear to implicate common neural regions. Here we discuss a unifying model in which the angular gyrus forms part of a wider LPC system with a core underlying neurocomputational function; the multi-sensory buffering of spatio-temporally extended representations. We review the principles derived from computational modelling with neuroimaging task data and functional and structural connectivity measures that underpin the unified neurocomputational framework. We propose that although a variety of cognitive activities might draw on shared underlying machinery, variations in task preference across angular gyrus, and wider LPC, arise from graded changes in the underlying structural connectivity of the region to different input/output information sources. More specifically, we propose two primary axes of organisation: a dorsal–ventral axis and an anterior–posterior axis, with variations in task preference arising from underlying connectivity to different core cognitive networks (e.g. the executive, language, visual, or episodic memory networks).

Fast Mapping (FM) is an incidental learning process that is hypothesised to allow rapid, cortical-based memory formation, independent of the normal, hippocampally-dependent episodic memory system. Recently, Coutanche and Thompson-Schill (2014) reported evidence for a learning advantage under an FM condition over a more conventional explicit learning condition (EE) in healthy young people using an implicit measure of learning, namely same-day lexical integration using a category (man-made/natural) decision task. They reported that under FM there were significantly slower RTs to hermit words, i.e., “galaxy”, whose made-up neighbours, i.e., “ganaxy” has been incidentally learned as unfamiliar animal name during the study phase; there was no slowing in the EE condition. They concluded that this offered evidence of same-day lexical integration learning that was present following FM, but not EE. We ran a methodological replication with power of over 80% and N=56 young adults, but found no evidence of same-day lexical competition (i.e., slowing) following either FM or EE. However, a post-hoc analysis produced an interesting significant result. In all learning conditions ‘names’ (i.e, made-up neighbours, e.g., “ganaxy”, “naskin”) had been incidentally learned as unfamiliar animal names; we found facilitation (i.e., speeding) for natural words, e.g.,“galaxy”, but slowing for man-made words, e.g., “napkin” under the FM condition, suggesting a facilitatory semantic priming effect, instead of a inhibitory lexical competition effect. We now wish to attempt to replicate this significant semantic priming effect, which would further inform the mechanisms of FM learning. Our experiment will have six between-participant conditions: 1 FM, 1 FM-r, and 1 EE condition where the ‘names’ are for unfamiliar animals, and 1 FM, 1 FM-r, and 1 EE condition where ‘names’ are unfamiliar man-made objects. We predict that when studied neighbours (e.g., “ganaxy”, “naskin”) are names for (1) unfamiliar animal pictures, natural words (galaxy) will be speeded and man-made words (napkin) will be slowed, but for (2) unfamiliar man-made objects, natural words (galaxy) will be slowed and man-made words (napkin) will be speeded.

Prereg posters are conference posters that present planned scientific projects (Tibon, CBU Open Science Committee, & Henson, 2018) and were recently adopted by the BNA2019 Festival of Neuroscience (https://meetings.bna.org.uk/bna2019/). The organisers of the event collected survey data about prereg posters, to provide empirical evidence for their value. Nearly a fifth of all presented posters at the BNA2019 Festival conformed to the new prereg format, covering a diverse range of neuroscience topics and disciplines, and the overall impression was that they were enthusiastically welcomed. The survey data were collected at two time points (before and after the event), via two different surveys. We analyse data from the questionnaire items that address three main themes: prereg posters as means to (1) receive valuable feedback, (2) promote Open Science, and (3) support Early Career Researchers (ECRs).

Events that conform to our expectations, i.e, are congruent with our world knowledge or schemas, are better remembered than unrelated events. Yet events that conflict with schemas can also be remembered better. We examined this apparent paradox in four experiments, in which schemas were established by training ordinal relationships between randomly-paired objects, while episodic memory was tested for the number of objects on each trial. Better memory was found for both congruent and incongruent trials, relative to unrelated trials, producing memory performance that was a “U-shaped” function of congruency. Furthermore, the incongruency advantage, but not congruency advantage, emerged even if the information probed by the memory test was irrelevant to the schema, while the congruency advantage, but not incongruency advantage, also emerged after initial encoding. Schemas therefore augment episodic memory in multiple ways, depending on the match between novel and existing information.

The use of linear mixed-effect models is becoming increasingly popular in neuroimaging. These models extend the simple linear models by allowing both fixed and random effects, and are particularly useful for clustered and hierarchical data. These are the materials from a session held at the MRC Cognition and Brain Sciences Unit, Cambridge, UK, where Delia introduced the concept of linear mixed-effect models and discussed when they should be used. Roni then demonstrated how these are implemented with R. Alex reviewed some advanced topics, including estimation of parameters (family parameters and random effects) as well as the use of Bayesian statistics.

Data and R scripts or FM with implicit memory measure project. # Cooper,E., Tibon, R., Greve, A.,& Henson, R.N.(2021)"No evidence of a fast mapping advantage in healthy adults using an implicit memory measure: Failures to replicate the results of Coutanche and Thompson-Schill (2014)"

Although it is often assumed that memory of episodic associations requires recollection, it has been suggested that, when stimuli are experienced as a unit, earlier memory processes might contribute to their subsequent associative recognition. We investigated the effects of associative relations and perceptual domain during episodic encoding on the ability to utilize early memory processes to retrieve associative information. During the study phase, participants encoded compound and noncompound words pairs, presented either to the same sensory modality (visual presentation) or to different sensory modalities (audiovisual presentation). At the test phase, they discriminated between old, rearranged, and new pairs while ERPs were recorded. In an early ERP component, differences related to associative memory emerged only for compounds, regardless of their encoding modality. These findings indicate that episodic retrieval of compound words can be supported by early-onset recognition processes regardless of whether both words were presented to the same or different sensory modalities, and suggests that unitization can operate at an abstract level, across a broad range of materials.

Highlights • We assessed behavioral reconsolidation interference in episodic memory. • Employed within-subjects paradigm measuring direct memory strength. • Three experiments found no effects of reminder-potentiated interference. • Null effects were substantiated by Bayesian analyses. • Highlights boundary conditions for behavioral reconsolidation interference effects., In studies of behavioral reconsolidation interference, reactivation of a consolidated memory using some form of reminder is followed by the presentation of new information that can cause interference with that memory. Under these conditions, the interference not only impairs retrieval by indirect processes such as cue interference, but supposedly disrupts the original memory trace directly. Almost all studies of behavioral reconsolidation interference in episodic memory in humans have employed between-subjects paradigms, and deduced reminder effects from intrusion errors. Such studies might introduce confounds arising, for example, from differences in retrieval strategies engendered by the pre-test treatments. We therefore set out to examine whether behavioral reconsolidation interference in episodic memory might be demonstrated within-subjects and by direct memory strength rather than intrusion errors. In three separate experiments, we attempted to disrupt reconsolidation of episodic object-picture memory using a reminder + retroactive interference manipulation. We applied the manipulation over three consecutive days, using a forced-choice recognition test without intrusions from interfering learning, keeping all other study and test parameters constant. No effects of reminder-potentiated interference were observed for measures of accuracy, response times, subjective expressions of recollection, or levels of confidence, as substantiated by Bayesian analyses. These results highlight the difficulty of observing clear behavioral reconsolidation interference effects within-subjects in human episodic memory, and provide some indications of what might be boundary conditions for its demonstration.

It has been proposed that although unitization benefits associative episodic memory, such benefits may exact a cost of poorer subsequent memory for the individual component elements forming these associations. However, unitization effects on item memory may be a function of whether items were unitized in a top-down fashion (i.e., through encoding instructions) or in a bottom-up fashion (through inherent semantic relationships between the associated items). We hypothesized that semantic relatedness unitization would benefit item recognition due to processing fluency that affords availability of more encoding resources. In two experiments, we tested how relatedness unitization of object pictures at encoding affected subsequent item recognition. The first experiment used a between-subject inclusion/exclusion paradigm, while the second experiment used a within-subject three-alternative choice recognition test. Results of both experiments revealed that semantic relatedness unitization benefited item memory. However, both accuracy patterns and error analyses indicated that such relatedness-based unitization improved memory for an item’s gist (i.e., its categorical identity), but not for its visual details. This indicates that that associative relatedness at encoding strengthens representations of the semantic identity of individual stimuli, but not necessarily of their perceptual details, possibly because of enhanced semantic elaboration at encoding.