Working memory load impairs transfer learning in human adults.

Transfer of learning refers to successful application of previously acquired knowledge or skills to novel settings. Although working memory (WM) is thought to play a role in transfer learning, direct evidence of the effect of limitations in WM on transfer learning is lacking. To investigate, we used an acquired equivalence paradigm that included tests of association and transfer learning. The effects of imposing an acute WM limitation on young adults was tested (within-subjects design: N = 27 adults; Mage = 24 years) by conducting learning transfer tests concurrent with a secondary task that required carrying a spatial WM load when performing the learned/transfer trial (Load condition) to acutely limit WM resources or no WM load (No-Load condition; WM was unloaded prior to performing the learned/transfer trial). Analyses showed that although success on the transfer trials was high in the No-Load condition, performance dropped to chance in the Load condition. Performance on tests of learned associations remained high in both conditions. These results indicate that transfer of learning depends on access to WM resources and suggest that even healthy young individuals may be affected in their ability to cross-utilize knowledge when cognitive resources become scarce, such as when engaging in two tasks simultaneously (e.g., using satellite navigation while driving).

Banknote authenticity is signalled by rapid neural responses.

Authenticating valuable objects is widely assumed to involve protracted scrutiny for detection of reproduction flaws. Yet, accurate authentication of banknotes is possible within one second of viewing, suggesting that rapid neural processes may underpin counterfeit detection. To investigate, we measured event-related brain potentials (ERPs) in response to briefly viewed genuine or forensically recovered counterfeit banknotes presented in a visual oddball counterfeit detection task. Three ERP components, P1, P3, and extended P3, were assessed for each combination of banknote type (genuine, counterfeit) and overt response ("real", "fake"). P1 amplitude was greater for oddballs, demonstrating that the initial feedforward sweep of visual processing yields the essential information for differentiating genuine from counterfeit. A similar oddball effect was found for P3. The magnitude of this P3 effect was positively correlated with behavioural counterfeit sensitivity, although the corresponding correlation for P1 was not. For the extended P3, amplitude was greatest for correctly detected counterfeits and similarly small for missed counterfeits, incorrectly and correctly categorised genuine banknotes. These results show that authentication of complex stimuli involves a cascade of neural processes that unfolds in under a second, beginning with a very rapid sensory analysis, followed by a later decision stage requiring higher level processing.

Age, BMI, and inflammation: Associations with emotion recognition.

Experimental studies show that inflammation impairs the ability to interpret the mental state of another person, denoted theory of mind (ToM). The current study attempted a conceptual replication in states associated with elevated low-grade inflammation, i.e., high body weight and advanced age. Ninety young (M = 26.3 years, SD = 4.1) or older (M = 70.7 years, SD = 4.0) participants with either a normal body mass index (BMI) (M = 22.4, SD = 2.2) or high BMI (M = 33.1, SD = 3.8) completed the Reading the Mind in the Eyes Test (RMET) to assess emotion recognition. Plasma interleukin-6 (IL-6) level was measured to index low-grade inflammation. As anticipated, elevated IL-6 levels were found with higher BMI, although not with increased age. IL-6 was associated with poorer task performance, independent of potential demographic and health confounders (e.g., sex, education, smoking status, alcohol intake, presence of medical conditions, and medication intake). Analyses also revealed an interaction whereby young individuals with a high BMI showed worse RMET performance compared to their normal BMI counterparts, whereas the opposite pattern was found in older individuals. The present observational study replicated experimental results showing that elevated low-grade inflammation is correlated with a lower ability to infer the mental states of others. These findings suggest that also naturalistic conditions of (protracted) low-grade inflammation may alter emotion recognition.

Value associations bias ensemble perception.

Ensemble perception refers to awareness of average properties, e.g. size, of "noisy" elements that often comprise visual arrays in natural scenes. Here, we asked how ensemble perception might be influenced when some but not all array elements are associated with monetary reward. Previous studies show that reward associations can speed object processing, facilitate selection, and enhance working-memory maintenance, suggesting they may bias ensemble judgments. To investigate, participants reported the average element size of brief arrays of different-sized circles. In the learning phase, all circles had the same color, but different colors produced high or low performance-contingent rewards. Then, in an unrewarded test phase, arrays comprised three spatially inter-mixed subsets, each with a different color, including the high-reward color. In different trials, the mean size of the subset with the high-reward color was smaller, larger, or the same as the ensemble mean. Ensemble size estimates were significantly biased by the high-reward-associated subset, showing that value associations modulate ensemble perception. In the test phase of a second experiment, a pattern mask appeared immediately after array presentation to limit top-down processing. Not only was value-biasing eliminated, ensemble accuracy improved, suggesting that value associations distort consciously available ensemble representation via late high-level processing.

Inflammation Mediates Body Weight and Ageing Effects on Psychomotor Slowing.

Inflammation (immune system activation) affects neuronal function and may have consequences for the efficiency and speed of functional brain processes. Indeed, unusually slow psychomotor speed, a measure predictive of behavioural performance and health outcomes, is found with obesity and ageing, two conditions also associated with chronic inflammation. Yet whether inflammation is the mediating factor remains unclear. Here, we assessed inflammation by indexing interleukin-6 level in blood and measured psychomotor speed as well as indices of selective visual attention in young (mean = 26 years) or old (mean = 71 years) adults (N = 83) who were either lean or currently significantly overweight (mean body mass index = 22.4 and 33.8, respectively). Inflammation was positively and significantly correlated with psychomotor speed, age, and body mass index but not with attention measures. Using mediation analyses we show for the first time that inflammation fully accounts for the significant psychomotor slowing found in those with high BMI. Moreover, we further show that age-related psychomotor slowing is partially mediated by inflammation. These findings support the proposal that reducing inflammation may mitigate weight- and age-related cognitive decline and thereby improve performance on daily tasks and health outcomes more generally.

Loneliness in healthy young adults predicts inflammatory responsiveness to a mild immune challenge in vivo.

The established link between loneliness and poor health outcomes may stem from aberrant inflammatory regulation. The present study tested whether loneliness predicted the inflammatory response to a standardised in vivo immune challenge. Using a within-subjects double blind placebo-controlled design, 40 healthy men (mean age = 25, SD = 5) received a Salmonella Typhi vaccination (0.025 mg; Typhim Vi, Sanofi Pasteur, UK) and placebo (saline) on two separate occasions. Loneliness was assessed using the R-UCLA loneliness scale. Regression analyses showed that those that reported feeling more lonely exhibited an elevated interleukin-6 response (ß = 0.564, 95% confidence interval [0.003, 0.042], p < .05). This association withstood adjustment for potentially confounding variables, including age, sleep quality, socio-emotional factors, and health factors. The present findings are in line with evidence that loneliness may shift immune system responsivity, suggesting a potential biobehavioural pathway linking loneliness to impaired health.

Selective effects of acute low-grade inflammation on human visual attention.

Illness is often accompanied by perceived cognitive sluggishness, a symptom that may stem from immune system activation. The current study used electroencephalography (EEG) to assess how inflammation affected three different distinct attentional processes: alerting, orienting and executive control. In a double-blinded placebo-controlled within-subjects design (20 healthy males, mean age = 24.5, SD = 3.4), Salmonella typhoid vaccination (0.025 mg; Typhim Vi, Sanofi Pasteur) was used to induce transient mild inflammation, while a saline injection served as a placebo-control. Participants completed the Attention Network Test with concurrent EEG recorded 6 h post-injection. Analyses focused on behavioral task performance and on modulation of oscillatory EEG activity in the alpha band (9-12 Hz) for alerting as well as orienting attention and frontal theta band (4-8 Hz) for executive control. Vaccination induced mild systemic inflammation, as assessed by interleukin-6 (IL-6) levels. While no behavioral task performance differences between the inflammation and placebo condition were evident, inflammation caused significant alterations to task-related brain activity. Specifically, inflammation produced greater cue-induced suppression of alpha power in the alerting aspect of attention and individual variation in the inflammatory response was significantly correlated with the degree of alpha power suppression. Notably, inflammation did not affect orienting (i.e., alpha lateralization) or executive control (i.e., frontal theta activity). These results reveal a unique neurophysiological sensitivity to acute mild inflammation of the neural network that underpins attentional alerting functions. Observed in the absence of performance decrements, these novel findings suggest that acute inflammation requires individuals to exert greater cognitive effort when preparing for a task in order to maintain adequate behavioral performance.

Strategic Eye Movements are Used to Support Object Authentication.

Authentication is an important cognitive process used to determine whether one's initial identification of an object is corroborated by additional sensory information. Although authentication is critical for safe interaction with many objects, including food, websites, and valuable documents, the visual orienting strategies used to garner additional sensory data to support authentication remain poorly understood. When reliable visual cues to counterfeit cannot be anticipated, distributing fixations widely across an object's surface might be useful. However, strategic fixation of specific object-defining attributes would be more efficient and should lead to better authentication performance. To investigate, we monitored eye movements during a repetitive banknote authentication task involving genuine and counterfeit banknotes. Although fixations were distributed widely across the note prior to authentication decisions, preference for hard-to mimic areas and avoidance of easily mimicked areas was evident. However, there was a strong tendency to initially fixate the banknote's portrait, and only thereafter did eye movement control appear to be more strategic. Those who directed a greater proportion of fixations at hard-to-mimic areas and resisted more easily mimicked areas performed better on the authenticity task. The tendency to deploy strategic fixation improved with experience, suggesting that authentication benefits from precise visual orienting and refined categorisation criteria.

Priming by motivationally salient distractors produces hemispheric asymmetries in visual processing.

Stimuli that reliably herald the availability of rewards or punishers can acquire value associations, potentially imbuing them with emotional significance and attentional prioritization. Previous work has shown that an emotional stimulus (prime) presented just prior to an attention-demanding task disrupts performance in a lateralized manner that is independent of the prime's emotional valence. Here, we asked whether neutral stimuli with acquired value associations would similarly disrupt attention. In two experiments, adult participants first learned to associate specific face or chair stimuli with a high or low probability of either winning or losing points. These conditioned stimuli then served as primes in a speeded letter-search task. Primes with high versus low outcome probability, regardless of valence, slowed search for targets appearing in the left but not the right visual hemifield, mirroring previous results using emotional primes, and suggesting that motivational mechanisms that compete for control with non-emotional cognitive processes are right-lateralized in the human brain.

Low-grade inflammation decreases emotion recognition - Evidence from the vaccination model of inflammation.

The ability to adequately interpret the mental state of another person is key to complex human social interaction. Recent evidence suggests that this ability, considered a hallmark of 'theory of mind' (ToM), becomes impaired by inflammation. However, extant supportive empirical evidence is based on experiments that induce not only inflammation but also induce discomfort and sickness, factors that could also account for temporary social impairment. Hence, an experimental inflammation manipulation was applied that avoided this confound, isolating effects of inflammation and social interaction. Forty healthy male participants (mean age = 25, SD = 5 years) participated in this double-blind placebo-controlled crossover trial. Inflammation was induced using Salmonella Typhi vaccination (0.025 mg; Typhim Vi, Sanofi Pasteur, UK); saline-injection was used as a control. About 6 h 30 m after injection in each condition, participants completed the Reading the Mind in the Eyes Test (RMET), a validated test for assessing how well the mental states of others can be inferred through observation of the eyes region of the face. Vaccination induced systemic inflammation, elevating IL-6 by +419% (p < .001), without fever, sickness symptoms (e.g., nausea, light-headedness), or mood changes (all p's > .21). Importantly, compared to placebo, vaccination significantly reduced RMET accuracy (p < .05). RMET stimuli selected on valence (positive, negative, neutral) provided no evidence of a selective impact of treatment. By utilizing an inflammation-induction procedure that avoided concurrent sicknesses or symptoms in a double-blinded design, the present study provides further support for the hypothesis that immune activation impairs ToM. Such impairment may provide a mechanistic link explaining social-cognitive deficits in psychopathologies that exhibit low-grade inflammation, such as major depression.

Value conditioning modulates visual working memory processes.

Learning allows the value of motivationally salient events to become associated with stimuli that predict those events. Here, we asked whether value associations could facilitate visual working memory (WM), and whether such effects would be valence dependent. Our experiment was specifically designed to isolate value-based effects on WM from value-based effects on selective attention that might be expected to bias encoding. In a simple associative learning task, participants learned to associate the color of tinted faces with gaining or losing money or neither. Tinted faces then served as memoranda in a face identity WM task for which previously learned color associations were irrelevant and no monetary outcomes were forthcoming. Memory was best for faces with gain-associated tints, poorest for faces with loss-associated tints, and average for faces with no-outcome-associated tints. Value associated with 1 item in the WM array did not modulate memory for other items in the array. Eye movements when studying faces did not depend on the valence of previously learned color associations, arguing against value-based biases being due to differential encoding. This valence-sensitive value-conditioning effect on WM appears to result from modulation of WM maintenance processes.

How Attention Changes in Response to Incentives.

Although the performance of simple cognitive tasks can be enhanced if an incentive is provided, the mechanisms enabling such motivational control are not known. This study sought to uncover how mechanisms of attention and readiness are altered by reward-associated incentive stimuli. We measured EEG/ERP activity as human adults viewed a high- or low-incentive cue, experienced a short preparation interval, and then performed a simple visual search task to gain the predicted reward. Search performance was faster with high versus low incentives, and this was accompanied by distinct incentive-related EEG/ERP patterns at each phase of the task (incentive, preparation, and search). First, and most surprisingly, attention to high but not low incentive cues was actively suppressed, as indexed by a PD component in response to the incentive display. During the subsequent preparation interval, neural oscillations in the alpha frequency range were reduced after high-incentive cues, indicating heightened visual readiness. Finally, attentional orienting to the target in the search array was deployed with relatively little effort on high-incentive trials, as indexed by a reduced N2pc component. These results reveal the chain of events by which the brain's executive control mechanisms respond to incentives by altering the operation of multiple processing systems to produce optimal performance.

Gestational weight change in women attending a group antenatal program aimed at addressing obesity in pregnancy in New South Wales, Australia.

INTRODUCTION: The prevalence of obesity in Australia among women of childbearing age has doubled over the past 2 decades. Obesity is associated with complications for women and their newborns during pregnancy and birth. Limiting gestational weight gain can reduce perinatal complications and postnatal weight retention, but evidence supporting interventions designed to assist obese pregnant women to manage their weight gain in pregnancy is inconclusive. The aim of this article is to describe the gestational weight change of a cohort of obese pregnant women enrolled in a group antenatal program aimed at assisting them to limit their weight gain in pregnancy to levels recommended by the US Institute of Medicine. METHODS: The program was jointly developed by 2 metropolitan maternity services in New South Wales, Australia. This is a descriptive study that presents select data for women enrolled in the program. Body mass index (BMI), prepregnancy weight, last pregnancy weight, and selected clinical outcomes were recorded for 82 obese women enrolled in the program during the evaluation period of 14 months. Data were analyzed using nonparametric tests: the chi-square and the Mann-Whitney U tests. RESULTS: Parity was associated with prepregnancy BMI, with women of higher parity having higher BMIs. Women with higher BMIs had a significantly lower gestational weight gain than women with lower BMIs. Overall, 27% of women enrolled in the program gained the recommended 5 to 9 kg, 27% gained less than this amount, and 46% gained more. DISCUSSION: Evidence supporting interventions designed to assist obese pregnant women to manage their weight gain in pregnancy is lacking. This innovative, collaborative program shows promise, as early results compare favorably with international comparisons.

Value learning modulates goal-directed actions.

With experience, particular objects can predict good or bad outcomes. This alters our perceptual response to them: Reliable predictors of salient outcomes are recognized faster and better than unreliable predictors, regardless of the value (gain, loss) of the outcome they predict. When attentional resources are constrained, learned value associations matter, causing recognition of gain-associated objects to be spared. Here, we ask how learned predictiveness and value change the way we interact with potentially rewarding objects. After associating virtual objects (drinking flutes) with monetary gains or losses, reaching for and grasping corresponding real objects depended on the object's learned value. Action was faster when directed at objects that previously predicted outcomes more rather than less consistently, regardless of value. Conversely, reaches were more direct for gain- than for loss-associated objects, regardless of their predictiveness. Action monitoring thus reveals how value learning components become accessible during action.

A threatening face in the crowd: effects of emotional singletons on visual working memory.

Faces with threatening versus positive expressions are better remembered in visual working memory (WM) and are especially effective at capturing attention. We asked how the presence of a single threatening or happy face affects WM for concurrently viewed faces with neutral expressions. If threat captures attention and attention determines WM, then a WM performance cost for neutral faces should be evident. However, if threat boosts processing in an object-specific, noncompetitive manner, then no such costs should be produced. Participants viewed three neutral and one angry or happy face for 2 s. Face recognition was tested 1 s later. Although WM was better for singletons than nonsingletons and better for angry versus happy singletons, WM for neutral faces remained unaffected by either singleton. These results, combined with eye movement and response time analyses, argue against a selective attention account of threat-based benefits to WM and support object-specific enhancement via threat processing.

Angry expressions strengthen the encoding and maintenance of face identity representations in visual working memory.

Visual working memory (WM) for face identities is enhanced when faces express negative versus positive emotion. To determine the stage at which emotion exerts its influence on memory for person information, we isolated expression (angry/happy) to the encoding phase (Experiment 1; neutral test faces) or retrieval phase (Experiment 2; neutral study faces). WM was only enhanced by anger when expression was present at encoding, suggesting that retrieval mechanisms are not influenced by emotional expression. To examine whether emotional information is discarded on completion of encoding or sustained in WM, in Experiment 3 an emotional word categorisation task was inserted into the maintenance interval. Emotional congruence between word and face supported memory for angry but not for happy faces, suggesting that negative emotional information is preferentially sustained during WM maintenance. Our findings demonstrate that negative expressions exert sustained and beneficial effects on WM for faces that extend beyond encoding.

Learning through authentic assessment: an evaluation of a new development in the undergraduate midwifery curriculum.

Assessment is a powerful influence on learning, and can form an important strategy amongst a variety of teaching and learning approaches. Authentic assessment activities are designed to mimic the complexity of 'real world' situations that students may encounter in professional life, and require the application of a combination of skills related to knowledge, skills and attitude. We undertook a small-scale evaluation using a qualitative descriptive design to explore the feasibility and usefulness of an authentic assessment item that focused on a common clinical scenario in midwifery practice, female catheterisation. Seven third year Bachelor of Midwifery students and three teaching staff volunteered to participate in the project. During the process the students videoed the scenario for peer assessment, developed marking criteria, completed an online survey and participated in a focus group. The findings demonstrated that the students' confidence, knowledge and skills improved as a result of participating in the assessment item and they rated it positively for use in the Bachelor of Midwifery curriculum as a means of increasing real world assessment activities. It is anticipated that this learning strategy will be further refined and integrated in various ways into other clinical midwifery subjects in the midwifery curriculum.

"Distracters" Do Not Always Distract: Visual Working Memory for Angry Faces is Enhanced by Incidental Emotional Words.

We are often required to filter out distraction in order to focus on a primary task during which working memory (WM) is engaged. Previous research has shown that negative versus neutral distracters presented during a visual WM maintenance period significantly impair memory for neutral information. However, the contents of WM are often also emotional in nature. The question we address here is how incidental information might impact upon visual WM when both this and the memory items contain emotional information. We presented emotional versus neutral words during the maintenance interval of an emotional visual WM faces task. Participants encoded two angry or happy faces into WM, and several seconds into a 9 s maintenance period a negative, positive, or neutral word was flashed on the screen three times. A single neutral test face was presented for retrieval with a face identity that was either present or absent in the preceding study array. WM for angry face identities was significantly better when an emotional (negative or positive) versus neutral (or no) word was presented. In contrast, WM for happy face identities was not significantly affected by word valence. These findings suggest that the presence of emotion within an intervening stimulus boosts the emotional value of threat-related information maintained in visual WM and thus improves performance. In addition, we show that incidental events that are emotional in nature do not always distract from an ongoing WM task.

Learned predictiveness speeds visual processing.

When humans learn that the presence of a cue predicts the likelihood of an outcome, they can exploit this learned predictiveness, such that formation of subsequent associations between that cue and new outcomes is facilitated. Could such enhanced selection for association arise early enough to facilitate low-level visual processing? In a test of this possibility, adult volunteers first engaged in a value-learning task involving faces that were differentially predictive of monetary wins or losses. Later, in a simple recognition task, these faces were briefly presented for a variable duration and then masked. The critical presentation duration needed to produce criterion-level recognition was measured to index the visual processing speed for each learned face. Critical duration was significantly shorter for stimuli with high learned predictiveness than for stimuli with low learned predictiveness, regardless of whether they were associated with wins or losses. These results show that neural mechanisms involved in predicting future outcomes are able to modulate visual processing efficiency, probably via cortical feedback processes.

Emotional distraction unbalances visual processing.

Brain mechanisms used to control nonemotional aspects of cognition may be distinct from those regulating responses to emotional stimuli, with activity of the latter being detrimental to the former. Previous studies have shown that suppression of irrelevant emotional stimuli produces a largely right-lateralized pattern of frontal brain activation, thus predicting that emotional stimuli may invoke temporary, lateralized costs to performance on nonemotional cognitive tasks. To test this, we briefly (85 ms) presented a central, irrelevant, expressive (angry, happy, sad, or fearful) or neutral face 100 ms prior to a letter search task. The presentation of emotional versus neutral faces slowed subsequent search for targets appearing in the left, but not the right, hemifield, supporting the notion of a right-lateralized, emotional response mechanism that competes for control with nonemotional cognitive processes. Presentation of neutral, scrambled, or inverted neutral faces produced no such laterality effects on visual search response times.