The level-of-processing (LoP) hypothesis postulates that transition from unaware to aware visual stimuli is either graded or dichotomous depending on the depth of stimulus processing. Humans can be progressively aware of the low-level features, such as colors or shapes, while the high-level features, such as semantic category, enter consciousness in an all-or none fashion. Unlike in vision, sounds always unfold in time, which might require mechanisms dissimilar from visual processing. We tested the LoP hypothesis in hearing for the first time by presenting participants with words of different categories, spoken in different pitches near the perceptual threshold. We also assessed whether different electrophysiological correlates of consciousness, the auditory awareness negativity (AAN) and late positivity (LP), were associated with LoP. Our findings indicate that LoP also applies to the auditory modality. AAN is an early correlate of awareness independent of LoP, while LP was modulated by awareness, performance accuracy and the level of processing.

OBJECTIVE: The Australian Dietary Guidelines are currently being revised and ultra-processed foods have been identified as a high priority action area. To better understand how well the current Dietary Guidelines align with level of processing classifications, the aim of this study was to assess the alignment between the Australian Dietary Guidelines and the NOVA classification system for classifying the healthiness of packaged foods.
METHODS: Data were sourced from the Australian FoodSwitch dataset, which included 28 071 packaged food and beverage products available in major Australian supermarkets in 2022. Products were classified as (i) core or discretionary (Australian Dietary Guidelines) and (ii) non-ultra-processed or ultra-processed (NOVA). Agreement between the two systems (core vs. non-ultra-processed and discretionary vs. ultra-processed) was evaluated using the kappa statistic.
RESULTS: There was \'moderate\' agreement (κ = 0.41, 95% CI: 0.40-0.42) between the Australian Dietary Guidelines and the NOVA system, with 69.8% of products aligned across the two systems. Alignment was more common for discretionary foods (80.6% were ultra-processed) than core foods (59.9% aligned were not-ultra-processed). Food categories exhibiting the strongest levels of alignment included confectionary, foods for specific dietary use, and egg and egg products. Discordance was most common for convenience foods, sugars, honey and related products, and cereal and grain products.
CONCLUSIONS: Despite moderate alignment between the Australian Dietary Guidelines and NOVA, the discordance observed for almost one-third of products highlights the opportunity to develop recommendations for ultra-processed foods within the guidelines to advise Australians how these foods should be considered as part of a healthy diet.

Faces are visual stimuli that convey rich social information. Previous experiments found better recognition for faces that were evaluated based on their social traits than on their perceptual features during encoding. Here, we ask whether this social-encoding benefit in face recognition is also found for categories of faces that we have no previous social experience with, such as other-race faces. To answer this question, we first explored whether social and perceptual evaluations for other-race faces are consistent and valid. We then asked whether social evaluations during encoding improve recognition for other-race faces. Results show that social and perceptual evaluations of own- and other-race faces were valid. We also found high agreement in social and perceptual evaluations across individuals from different races. This indicates that evaluations of other-race faces are not random but meaningful. Furthermore, we found that social evaluations facilitated face recognition regardless of race, demonstrating a social-encoding benefit for both own- and other-race faces. Our findings highlight the role of social information in face recognition and show how it can be used to improve recognition of categories of faces that are hard to recognize due to lack of experience with them.

The role hemispheric lateralization in the prefrontal cortex plays for episodic memory formation in general, and for emotionally valenced information in particular, is debated. In a randomized, double-blind, and sham-controlled design, healthy young participants (n = 254) performed 2 runs of encoding to categorize the perceptual, semantic, or emotionally valenced (positive or negative) features of words followed by a free recall and a recognition task. To resolve competing hypotheses about the contribution of each hemisphere, we modulated left or right dorsolateral prefrontal cortex (DLPFC) activity using transcranial direct current stimulation during encoding (1 mA, 20 min). With stimulation of the left DLPFC, but not the right DLPFC, encoding and free recall performance improved particularly for words that were processed semantically. In addition, enhancing left DLPFC activity increased memory formation for positive content while reducing that for negative content. In contrast, promoting right DLPFC activity increased memory formation for negative content. The left DLPFC assesses semantic properties of new memory content at encoding and thus influences how successful new episodic memories are established. Hemispheric laterlization-more active left DLPFC and less active right DLPFC-at the encoding stage shifts the formation of memory traces in favor of positively valenced content.

Face recognition benefits from associating social information to faces during learning. This has been demonstrated by better recognition for faces that underwent social than perceptual evaluations. Two hypotheses were proposed to account for this effect. According to the feature-elaboration hypothesis, social-evaluations encourage elaborated processing of perceptual information from faces (Winograd, 1981). According to a social-representation hypothesis, social-evaluations convert faces from a perceptual representation to a socially meaningful representation of a person. To decide between these two hypotheses, we ran a functional MRI study in which we functionally localized the posterior face-selective brain areas and social processing brain areas. Participants watched video-clips of young adults and were asked to study them for a recognition test, while making either perceptual evaluations or social evaluations about them. During the fMRI scan, participants performed an old/new recognition test. Behavioural findings replicated better recognition for faces that underwent social then perceptual evaluations. fMRI results showed higher response during the recognition phase for the faces that were learned socially than perceptually, in the social-brain network but not in posterior face-selective network. These results support the social-representation hypothesis and highlight the important role that social processing mechanisms, rather than purely perceptual processes, play in face recognition.

Episodic memory and attention impairments are frequently observed following a traumatic brain injury (TBI). Older adults are more affected than young adults after a TBI, partly because of the age-related neural and memory changes. Neural mechanisms underlying episodic memory deficits in older adults with chronic TBI remain to be investigated. The current study aimed to investigate the impact of TBI in older adults on the neural mechanisms of episodic encoding. Event-related potentials were recorded while 13 participants with mild-to-severe TBI and 14 matched controls were performing an episodic memory task in which the level of organizational strategy was manipulated through three encoding conditions. Participants were explicitly instructed to memorize words without any semantic relationship (Unrelated condition), words semantically related without any given strategies (Spontaneous condition) and words semantically related with provided category labels and organizational strategy (Guided condition). Behavioral performances indicated that older individuals with a TBI were impaired compared to matched controls whatever the condition. The electrophysiological findings showed a reduction of the P200 and LPC components amplitude in the TBI group relative to control group. Moreover, control participants without any neurological history showed a right frontal sustained activity only in the Spontaneous condition, whereas a right frontal asymmetry was observed in participants with chronic TBI whatever the encoding conditions. This was mainly the result of negative left frontal activity. These findings evidence neural dysfunctions underlying attentional and associative processes involved in memory strategies after a TBI sustained at an older age that are consistent with executive functions impairments.

Analogical reasoning was investigated among children with autism spectrum disorders (ASD) without intellectual disabilities and typical development (TD). Children were asked to select one of two targets in two conditions: (1) with and without spatial structure similarity; (2) with and without a perceptual distractor. Results demonstrate that children with ASD were able to select targets based on structural similarity, but this ability decreased to chance level when presented with a perceptual distractor. Everyday executive functions were positively correlated with structural selections among children with ASD. Results suggest that although children with ASD were able to select based on systematicity principle, perceptual distractor decreased their selection so that their cognitive system produced less structure similarities, that negatively affects spatial analogical reasoning.

A major concern in age-related cognitive decline is episodic memory (EM). Previous studies indicate that both resource and binding deficits contribute to EM decline. Environmental support by task manipulations encouraging stronger cognitive effort and deeper levels of processing may facilitate compensation for these two deficits. To clarify factors that can counteract age-related EM decline, we assessed effects of cognitive effort (four levels) and level of processing (LoP, shallow/deep) during encoding on subsequent retrieval. Young (YAs, N = 23) and older (OAs, N = 23) adults performed two incidental encoding tasks, deep/semantic and shallow/perceptual. Cognitive effort was manipulated by varying decision-making demands. EM performance, indexed by d-prime, was later tested using a recognition task. Results showed that regardless of LoP, increased cognitive effort caused higher d-primes in both age groups. Compared to YAs, OAs showed a lower d-prime after shallow encoding across all cognitive effort levels, and after deep encoding with low cognitive effort. Deep encoding with higher levels of cognitive effort completely eliminated these age differences. Our findings support an environmental-compensatory account of cognitive ageing and can have important therapeutic implications.

We aimed at investigating rapid effects of plasma cortisol elevations on the episodic memory phase of encoding or retrieval, and on the strength of the memory trace. Participants were asked either to select a word containing the letter \"e\" (shallow encoding task) or to judge if a word referred to a living entity (deep encoding task). We intravenously administered a bolus of 20mg of cortisol either 5 min before encoding or 5 min before retrieval, in a between-subjects design. The study included only male participants tested in the late afternoon, and neutral words as stimuli. When cortisol administration occurred prior to retrieval, a main effect of group emerged. Recognition accuracy was higher for individuals who received cortisol compared to placebo. The higher discrimination accuracy for the cortisol group was significant for words encoded during deep but not shallow task. Cortisol administration before encoding did not affect subsequent retrieval performance (either for deep or shallow stimuli) despite a facilitatory trend. Because genomic mechanisms take some time to develop, such a mechanism cannot apply to our findings where the memory task was performed shortly after the enhancement of glucocorticoid levels. Therefore, glucocorticoids, through non-genomic fast effects, determine an enhancement in episodic memory if administered immediately prior to retrieval. This effect is more evident if the memory trace is laid down through deep encoding operations involving the recruitment of specific neural networks.

BACKGROUND: Transcranial magnetic stimulation (TMS) can affect episodic memory, one of the main cognitive hallmarks of aging, but the mechanisms of action remain unclear.
OBJECTIVE: To evaluate the behavioral and functional impact of excitatory TMS in a group of healthy elders.
METHODS: We applied a paradigm of repetitive TMS - intermittent theta-burst stimulation - over left inferior frontal gyrus in healthy elders (n = 24) and evaluated its impact on the performance of an episodic memory task with two levels of processing and the associated brain activity as captured by a pre and post fMRI scans.
RESULTS: In the post-TMS fMRI we found TMS-related activity increases in left prefrontal and cerebellum-occipital areas specifically during deep encoding but not during shallow encoding or at rest. Furthermore, we found a task-dependent change in connectivity during the encoding task between cerebellum-occipital areas and the TMS-targeted left inferior frontal region. This connectivity change correlated with the TMS effects over brain networks.
CONCLUSIONS: The results suggest that the aged brain responds to brain stimulation in a state-dependent manner as engaged by different tasks components and that TMS effect is related to inter-individual connectivity changes measures. These findings reveal fundamental insights into brain network dynamics in aging and the capacity to probe them with combined behavioral and stimulation approaches.