Perceived health inequalities: are the UK and US public aware of occupation-related health inequality, and do they wish to see it reduced?

BACKGROUND: One underexamined factor in the study of lay views of socioeconomic health inequalities is occupation-related health. Examining health by occupational social class has a long history in the UK but has been comparatively overlooked in US public health literatures, where the relationship between health and work has attended more to hazard exposure. METHODS: Representative samples of the UK and US indicated the perceived and ideal lifespan of people working in "higher managerial/professional" and "routine" occupations. We examine perceptions of inequality and desires for equality across occupation groups as a function of country and key socio-demographic variables. RESULTS: 67.8% of UK and 53.7% of US participants identified that professionals live longer than routine workers. Multivariate models indicated that US participants were markedly less likely to be aware of occupation-related inequalities after controlling for age, gender, and education. Awareness was negatively related to age (in the US) and recent voting behaviours (both samples). Desiring equal life expectancy was less likely in the US sample, and less likely across both samples among older participants and those with lower levels of education. CONCLUSION: Employing a novel approach to measuring perceived and ideal life expectancy inequality, this is the first study to examine perceptions of lifespan inequality by occupational groups. It reports widespread understanding of the occupation-related gradient in lifespan and a desire that these inequalities be eliminated in the UK, but considerably less awareness and desire for equality in the US. Greater tolerance for social status inequalities in the US than other similar countries appear to also extend to differences in life expectancy.

Subjective socioeconomic status and agreement that health is determined by distal and proximal factors.

This report examines whether a person's subjective view of their rank relative to others in society-subjective socioeconomic status (SES)-is systematically related to views on distal and proximal determinants of ill-health. This was tested using cross-sectional data from 28,718 respondents from 27 countries who took part in the International Social Survey Programme (ISSP) in 2011. Adjusting for age and gender as well as income and education, mixed logistic regression models showed that subjective SES was negatively associated with the likelihood of agreeing with distal explanations for poor health (being poor or because of work/life environment) and positively associated with the likelihood of agreeing with health-related behaviours as a cause for poor health. Subjective SES was not related to agreement that genes influence health. These analyses introduce a social psychological factor into the lay understanding of health determinants and extend models of subjective status and attributional style to health explanations.

Age effects on associative memory for novel picture pairings.

Normal aging is usually accompanied by greater memory decline for associations than for single items. Though associative memory is generally supported by recollection, it has been suggested that familiarity can also contribute to associative memory when stimuli can be unitized and encoded as a single entity. Given that familiarity remains intact during healthy aging, this may be one route to reducing age-related associative deficits. The current study investigated age-related differences in associative memory under conditions that were expected to differentially promote unitization, in this case by manipulating the spatial arrangement of two semantically unrelated objects positioned relative to each other in either spatially implausible or plausible orientations. Event-related potential (ERP) correlates of item and associative memory were recorded whilst younger and older adults were required to discriminate between old, recombined and new pairs of objects. These ERP correlates of item and associative memory did not vary with plausibility, whereas behavioral measures revealed that both associative and item memory were greater for spatially plausible than implausible pair arrangements. Contrary to predictions, older adults were less able to take advantage of this memory benefit than younger participants. Potential reasons for this are considered, and these are informed by those lines of evidence which indicate older participants were less sensitive to the bottom-up spatial manipulation employed here. It is recommended that future strategies for redressing age-related associative deficits should take account of the aging brain's increasing reliance on pre-existing semantic associations.

The beneficial effect of testing: an event-related potential study.

The enhanced memory performance for items that are tested as compared to being restudied (the testing effect) is a frequently reported memory phenomenon. According to the episodic context account of the testing effect, this beneficial effect of testing is related to a process which reinstates the previously learnt episodic information. Few studies have explored the neural correlates of this effect at the time point when testing takes place, however. In this study, we utilized the ERP correlates of successful memory encoding to address this issue, hypothesizing that if the benefit of testing is due to retrieval-related processes at test then subsequent memory effects (SMEs) should resemble the ERP correlates of retrieval-based processing in their temporal and spatial characteristics. Participants were asked to learn Swahili-German word pairs before items were presented in either a testing or a restudy condition. Memory performance was assessed immediately and 1-day later with a cued recall task. Successfully recalling items at test increased the likelihood that items were remembered over time compared to items which were only restudied. An ERP subsequent memory contrast (later remembered vs. later forgotten tested items), which reflects the engagement of processes that ensure items are recallable the next day were topographically comparable with the ERP correlate of immediate recollection (immediately remembered vs. immediately forgotten tested items). This result shows that the processes which allow items to be more memorable over time share qualitatively similar neural correlates with the processes that relate to successful retrieval at test. This finding supports the notion that testing is more beneficial than restudying on memory performance over time because of its engagement of retrieval processes, such as the re-encoding of actively retrieved memory representations.

Control over recollection varies with context-type: ERP evidence from the exclusion task.

The left-parietal ERP old/new effect­an index of recollection­is often larger for classes of item to-be-endorsed as old (targets) than to-be-rejected items (nontargets), and this has been interpreted as an index of selective retrieval. The question of interest here was whether selective retrieval would be more pronounced when targets are allocated according to distinct conceptual encoding tasks than when designated according to spatial location. Participants saw words on the left/right side of fixation and made a pleasantness or function judgment to each. Across test-blocks, target designation varied according to the kind of task judgment or the study location. Robust target old/new effects were observed for both classes of target designation but the nontarget amplitude was smaller when conceptual information was targeted. The current data indicate that the class of to-be-retrieved information determines the extent to which recollection can be controlled when all other factors are held constant.

Is faster better? Effects of response deadline on ERP correlates of recognition memory in younger and older adults.

Aging studies generally suggest that recollection is impaired whereas familiarity-based recognition remains relatively preserved in healthy older adults. The present event-related potential (ERP) study explores whether age-related impairments in recognition memory can be reduced under conditions in which recognition decisions are primarily driven by familiarity. Old and young adults performed an item recognition task with perceptually rich visual stimuli. A response deadline procedure was employed following previous studies which have shown that limiting response times attenuates recollection but leaves familiarity relatively unaffected. Age effects on memory performance were large in the non-speeded response condition in which recollection contributes to performance. When response time was limited, performance differences between groups were negligible. In the non-speeded condition the ERP correlate of recollection was not detectable in old adults. Conversely, in the speeded condition ERP correlates of familiarity were obtained in both age groups, though attenuated for old adults. For old adults in the speeded condition a temporally extended posterior negativity was obtained which was more pronounced for low performing participants. The results suggest that even though the neural generators of the familiarity signal degrade with age, familiarity is an important contributor to recognition memory in older adults and can lead to a disproportional benefit in memory in conditions designed to specifically enhance familiarity-based responding.

Errorful and errorless learning: The impact of cue-target constraint in learning from errors.

The benefits of testing on learning are well described, and attention has recently turned to what happens when errors are elicited during learning: Is testing nonetheless beneficial, or can errors hinder learning? Whilst recent findings have indicated that tests boost learning even if errors are made on every trial, other reports, emphasizing the benefits of errorless learning, have indicated that errors lead to poorer later memory performance. The possibility that this discrepancy is a function of the materials that must be learned-in particular, the relationship between the cues and targets-was addressed here. Cued recall after either a study-only errorless condition or an errorful learning condition was contrasted across cue-target associations, for which the extent to which the target was constrained by the cue was either high or low. Experiment 1 showed that whereas errorful learning led to greater recall for low-constraint stimuli, it led to a significant decrease in recall for high-constraint stimuli. This interaction is thought to reflect the extent to which retrieval is constrained by the cue-target association, as well as by the presence of preexisting semantic associations. The advantage of errorful retrieval for low-constraint stimuli was replicated in Experiment 2, and the interaction with stimulus type was replicated in Experiment 3, even when guesses were randomly designated as being either correct or incorrect. This pattern provides support for inferences derived from reports in which participants made errors on all learning trials, whilst highlighting the impact of material characteristics on the benefits and disadvantages that accrue from errorful learning in episodic memory.

More ways than one: ERPs reveal multiple familiarity signals in the word frequency mirror effect.

Recent dual-process models of the word frequency mirror effect place absolute familiarity, an item׳s baseline familiarity at a given time point, as responsible for false alarm differences and recollection for hit rate differences between high and low frequency items. One of the earliest dual-process propositions, however, posits an additional relative familiarity mechanism which is sensitive to recent presentation but relative to the absolute familiarity of a particular item (Mandler, 1980). In this study, it was possible to map these three mechanisms onto known event-related potential (ERP) effects in an old/new recognition task with high and low frequency words. Contrasts between ERPs elicited by high and low frequency new items were assumed to index absolute familiarity, and the distribution of this effect from 300 to 600ms was topographically distinct from a temporally-overlapping midfrontally-distributed old/new effect which was larger for low than high frequency words, as would be expected from a relative familiarity mechanism. A later left parietal old/new effect, strongly linked to recollection, was only present for low frequency items. These frequency-sensitive amplitude differences for both old/new effects disappeared in a second recognition task in which old/new decisions were made under a time constraint, although the posterior absolute familiarity effect remained unaffected by the speeding of responses. The data support the assertion that three distinct recognition processes are affected by word frequency in recognition memory tasks, and the qualitatively distinct distributions associated with the two familiarity contrasts support the presence of two cognitively distinct familiarity mechanisms.

The FN400 is functionally distinct from the N400.

The FN400 refers to the early midfrontally-distributed difference between ERPs elicited by old and new items, which operates in a way consistent with a neural marker of familiarity-based recognition. Double dissociations between the FN400 and a later ERP index of recollection provide some of the most compelling evidence in support of dual-process models to date. It has recently been claimed, however, that there is no evidence that the FN400 is functionally distinct from the N400 index of implicit semantic priming (Voss, J., and Federmeier, K., FN400 potentials are functionally identical to N400 potentials and reflect semantic processing during recognition testing, Psychophysiology, 48, 532-546, 2011), challenging inferences made on the basis of this effect. We argue that the design employed to make this claim is flawed because it comprised a semantic priming manipulation embedded within a continuous recognition test which enabled recognition contrasts to be confounded by semantic processes in a number of ways. Here, ERPs were recorded from a design which avoided these confounds by employing a semantic priming paradigm which also served as the encoding phase for a surprise subsequent recognition test phase. An N400 effect elicited in the semantic priming task demonstrated the established centro-parietal maximum, whereas the difference between correctly responded to old and new ERPs in the recognition test was maximal over frontal sites in the same time window. When direct comparisons of the electrophysiological correlates of semantic priming and episodic recognition are recorded in a paradigm in which the two are not confounded, the FN400 reflects a qualitatively distinct effect from the N400.

Monetary rewards influence retrieval orientations.

Reward anticipation during learning is known to support memory formation, but its role in retrieval processes is so far unclear. Retrieval orientations, as a reflection of controlled retrieval processing, are one aspect of retrieval that might be modulated by reward. These processes can be measured using the event-related potentials (ERPs) elicited by retrieval cues from tasks with different retrieval requirements, such as via changes in the class of targeted memory information. To determine whether retrieval orientations of this kind are modulated by reward during learning, we investigated the effects of high and low reward expectancy on the ERP correlates of retrieval orientation in two separate experiments. The reward manipulation at study in Experiment 1 was associated with later memory performance, whereas in Experiment 2, reward was directly linked to accuracy in the study task. In both studies, the participants encoded mixed lists of pictures and words preceded by high- or low-reward cues. After 24 h, they performed a recognition memory exclusion task, with words as the test items. In addition to a previously reported material-specific effect of retrieval orientation, a frontally distributed, reward-associated retrieval orientation effect was found in both experiments. These findings suggest that reward motivation during learning leads to the adoption of a reward-associated retrieval orientation to support the retrieval of highly motivational information. Thus, ERP retrieval orientation effects not only reflect retrieval processes related to the sought-for materials, but also relate to the reward conditions with which items were combined during encoding.

Electrophysiologically dissociating episodic preretrieval processing.

Contrasts between ERPs elicited by new items from tests with distinct episodic retrieval requirements index preretrieval processing. Preretrieval operations are thought to facilitate the recovery of task-relevant information because they have been shown to correlate with response accuracy in tasks in which prioritizing the retrieval of this information could be a useful strategy. This claim was tested here by contrasting new item ERPs from two retrieval tasks, each designed to explicitly require the recovery of a different kind of mnemonic information. New item ERPs differed from 400 msec poststimulus, but the distribution of these effects varied markedly, depending upon participants' response accuracy: A protracted posteriorly located effect was present for higher performing participants, whereas an anteriorly distributed effect occurred for lower performing participants. The magnitude of the posterior effect from 400 to 800 msec correlated with response accuracy, supporting the claim that preretrieval processes facilitate the recovery of task-relevant information. Additional contrasts between ERPs from these tasks and an old/new recognition task operating as a relative baseline revealed task-specific effects with nonoverlapping scalp topographies, in line with the assumption that these new item ERP effects reflect qualitatively distinct retrieval operations. Similarities in these effects were also used to reason about preretrieval processes related to the general requirement to recover contextual details. These insights, alongside the distinct pattern of effects for the two accuracy groups, reveal the multifarious nature of preretrieval processing while indicating that only some of these classes of operation are systematically related to response accuracy in recognition memory tasks.

Requirements at retrieval modulate subsequent memory effects: An event-related potential study.

Neural indices of memory formation can be acquired by contrasting activity during study for items that are remembered or forgotten on a subsequent memory test. These "subsequent memory" effects vary with the stimulus types that are encoded, how they are encoded, the correspondences between study and test materials, and the time intervals between study and test phases. We investigated whether event-related potential (ERP) subsequent memory effects also vary with the content people must retrieve. Participants saw words on the left/right side of fixation, and made a drawing difficulty or pleasantness judgment to each. In separate test phases, participants were asked to remember study screen location, or which task judgment had been made. The ERP subsequent memory effects from these two tasks were functionally distinct, demonstrating for the first time that ERP subsequent memory effects dissociate according to what people are trying to retrieve.

Neural correlates of individual differences in strategic retrieval processing.

Processes engaged when information is encoded into memory are an important determinant of whether that information will be recovered subsequently. Also influential, however, are processes engaged at the time of retrieval, and these were investigated here by using event-related potentials (ERPs) to measure a specific class of retrieval operations. These operations were revealed by contrasts between ERPs elicited by new (unstudied) test items in distinct tasks, the assumption being that these contrasts index operations that are engaged in service of retrieval and that vary according to the demands of different retrieval tasks. Specific functional accounts of this class of retrieval processing operations assume that they influence the accuracy of memory judgments, and this experiment was designed to test for the first time whether this is in fact the case. Toward this end, participants completed 2 retrieval tasks while ERPs were acquired, and the extent to which processes were engaged differentially across tasks in service of retrieval was operationalized as the magnitude of the differences between the new-item ERPs that were elicited. This measure correlated positively with response accuracy on the tasks, which provides strong evidence that this class of retrieval processing operations benefits the accuracy of memory judgments.