Knowledge concerning domain-specific regularities in sequential structure has long been known to affect recall for serial order. However, very little work has been done toward specifying the exact role such knowledge plays. The present article proposes a theory of serial recall in structured domains, based on Bayesian decision theory and a set of representational assumptions proceeding from recent computational and neurophysiologic research. The theory suggests that the accuracy with which a target sequence will be recalled is influenced by two interacting factors:(1) the 'goodness' of the sequence, i.e. its fit with the sequencing constraints that characterize its source domain, and (2) the sequence's neighborhood relations, i.e. the degree to which it resembles other sequences in the source domain. A specific prediction of the theory is that recall will be relatively poor for target lists with high-goodness near neighbors (the good neighbor effect). This prediction was tested and confirmed in an experiment evaluating recall for sequences based on an artificial grammar.

The CANTAB battery of neuropsychological tests was used to compare the performance of 28 patients with unipolar depression with that of 22 age and IQ matched controls. The patients were impaired on almost all tests studied with deficits in pattern and spatial recognition memory, matching to sample, spatial span, spatial working memory and planning. Most of the patients showed at least some impairment and deficits were seen across cognitive domains. An important finding was the detrimental effect of failure on subsequent performance; having solved one problem incorrectly, patients were far more likely than controls to fail the subsequent problem. Superimposed on the general deficits, there were also specific deficits in executive tasks characteristic of frontostriatal dysfunction and deficits in mnemonic tasks characteristic of temporal lobe dysfunction. This combination of a specific form of motivational deficit, resulting in oversensitivity to negative feedback, and superimposed specific neuropsychological deficits were correlated with severity of depression. The most significant correlations were seen between mnemonic deficits and clinical rating scores. Comparisons of the deficits seen in the depressed patients in this study with other patient groups assessed with the CANTAB neuropsychological battery, showed that one of the hypotheses of the neuropsychological deficits in depression, that of "frontosubcortical' or "frontostriatal' dysfunction, was not supported. These findings are discussed in relation to the likely neural substrates of depression.

Three experiments investigated visual search for singleton feature targets. The critical dimension on which the target differed from the nontargets was either known in advance or unknown--that is, the critical difference varied either within a dimension or across dimensions. Previous work (Treisman, 1988) had shown that, while the search reaction time (RT) functions were flat in both conditions, there was an intercept cost for the cross-dimension condition. Experiment 1 examined whether this cost would disappear when responses could be based on the detection of any (target-nontarget) difference in the display (by requiring a "heterogeneity/homogeneity" decision). The cost remained. This argues that pop-out requires (or involves) knowledge of the particular dimension in which an odd-one-out target differs from the nontargets; furthermore, that knowledge is acquired through the elimination of dimensions not containing a target. In Experiment 2, the subjects had to eliminate (or ignore) one potential source of difference in order to give a positive response (displays could contain a "noncritical" difference requiring a negative response). The result was a comparatively large cost in the within-dimension (positive) condition. This can be taken to indicate that pop-out as such does not make available information as to the particular feature value in which the target differs from the nontargets. Experiment 3 examined whether search priorities can be biased in accordance with advance knowledge of the likely source of difference. The subjects were found to have a high degree of top-down control over what particular dimension to assign priority of checking to. The implication of the results for models of visual search and selection are discussed.

The neural mechanisms by which emotional and cognitive processing interact are unknown. Evidence from animal studies and neurological patients suggests that regions of the ventral striatum and orbitofrontal cortex, together with limbic structures such as the amygdala, are critical to such interactions. We used positron emission tomography to study the neural systems engaged by processing performance feedback under two conditions involving either a complex cognitive or a matched guessing task. The main activations associated with the processing of performance feedback under different task conditions involved foci in the medial caudate nucleus and the ventromedial orbitofrontal cortex. A differential modulation of these activations as a function of task type was observed. In particular the orbitofrontal activation associated with the presence of feedback was only seen in the guessing task. These data suggest that the ventral striatum and orbitofrontal cortex are involved in processing of feedback information, findings consistent with animal and neurological studies. We propose that differential activation associated with guessing compared to planning suggests enhanced neural processing of feedback when the outcome of a task is uncontrollable or when information must be assimilated across a number of trials to assess performance.

The literature suggests that doctors' and nurses' openness about communicating with the terminally ill and their families has increased in the past two or three decades, partly influenced by the hospice movement. The present study reports the perceptions of relatives, hospital doctors, general practitioners and nurses who knew a random sample of 639 adults dying in England in 1987. The results from professionals suggest a general preference for openness about illness and death, tempered by the consideration that bad news needs to be broken slowly, in a context of support, while recognising that not everyone wishes to know all. In practice people dying from cancer were more likely to be reported as knowing what their illness was and that they would die than were people dying from other conditions. This difference held when controlling for the fact that death was more likely to be medically expected in cancer. Comparisons with 1969 show that the increases were due largely to cancer patients being told the truth more frequently by hospital doctors. This may be due to changed practices, or to the increase in the number of hospital episodes in the last year of life. Nevertheless, situations of 'closed awareness' where relatives were told and patients were not, and situations where patients were left to guess the likely outcome for themselves, were still quite common in 1987. Nurses and hospice practitioners were only marginally involved in breaking bad news, this remaining the province of hospital doctors and general practitioners. Relatives in general praised the manner in which they and patients were told, although a small proportion reported insensitive practice. In retrospect a high proportion of both relatives and professionals felt that the levels of awareness were best as they were, although this preference may have been influenced by a desire to see things in a good light. Most relatives reported adequate support and information being given by professionals to them during the patient's illness. On the whole, doctors provided information, and friends and family provided emotional support to relatives. Again, hospital doctors played an increasingly important role compared to 1969 in providing information, with general practitioners' role decreasing in this area. Gaps in information included not being told enough about what was wrong with the patient, not being told the reasons for decisions about treatment and, to a lesser extent, not being given information about how to care for the patient.

BACKGROUND: Recent evidence suggests that an abnormal response to performance feedback may contribute to the wide-ranging neuropsychological deficits typically associated with depressive illness. The present research sought to determine whether the inability of depressed patients to utilize performance feedback advantageously is equally true for accurate and misleading feedback. METHOD: Patients with major depression and matched controls completed:(1) a visual discrimination and reversal task that featured intermittent and misleading negative feedback; and (2) feedback and no-feedback versions of a computerised test of spatial working memory. In the feedback version, negative feedback was accurate, highly informative, and could be used as a mnemonic aid. RESULTS: On the Probability Reversal task, depressed patients were impaired in their ability to maintain response set in the face of misleading negative feedback as shown by their increased tendency to switch responding to the 'incorrect' stimulus following negative reinforcement, relative to that of controls. Patients' ability to acquire and reverse the necessary visual discrimination was unimpaired. On the Spatial Working Memory task, depressed patients made significantly more between-search errors than controls on the most difficult trials, but their ability to use negative feedback to facilitate performance remained intact. CONCLUSIONS: The present results suggest that feedback can have different effects in different contexts. Misleading, negative feedback appears to disrupt the performance of depressed patients, whereas negative but accurate feedback does not. These findings are considered in the context of recent studies on reinforcement systems and their associated neurobiological substrates.

Education is an effective tool for modifying physician use of the laboratory. We compared two interventions by assigning 56 medical house officers into four groups: control group; feedback group, which received feedback concerning its use of tests; manual group, which received a manual concerning cost-effective laboratory use; and manual plus feedback group, which received both interventions. All intervention groups experienced significant decreases in test use. When we controlled for diagnosis, the manual plus feedback group had the most profound decrease (42%) in laboratory use, followed by the manual group. The feedback and control groups had no change. Attitudes and knowledge did not change. We conclude that one can, via simple techniques, modify house staff use of the outpatient laboratory. The less-expensive intervention was a cost-oriented manual, which may have a "sensitizing" rather than educational effect.

This article is based on an invited challenge address at the 1989 National Doctoral Forum related to future directions for substantive knowledge development. The focus is on the inclusion of caring knowledge into nursing's metaparadigm. Art and metaphor are used to make a case for caring knowledge and caring ontology as a metaphorical landscape for diverse epistemological "set pieces," all converging on a Commons Room of caring knowledge within a broader human and natural landscape. Such a framework links ontology and epistemology as both substance and form, and allows matter and spirit to be of a piece, but distinguishable; human caring knowledge then becomes Annie Dillard's "Absolute base" and "Holy the Firm."

As the rapidity with which medical knowledge is generated and disseminated becomes amplified, an increasing emphasis has been placed on the need for physicians to develop the skills necessary for life-long learning. One such skill is the ability to evaluate one's own deficiencies. A ubiquitous finding in the study of self-assessment, however, is that self-ratings are poorly correlated with other performance measures. Still, many educators view the ability to recognize and communicate one's deficiencies as an important component of adult learning. As a result, two studies have been performed in an attempt to improve upon this status quo. First, we tried to re-define the limits within which self-assessments should be used, using Rosenblit and Keil's argument that calibration between perceived and actual performance will be better within taxonomies that are regularly tested (e.g., factual knowledge) compared to those that are not (e.g., conceptual knowledge). Second, we tried to norm reference individuals based on both the performance of their colleagues and their own historical performance on McMaster's Personal Progress Inventory (a multiple choice question test of medical knowledge). While it appears that students are able to (a) make macro-level self-assessments (i.e., to recognize that third year students typically outperform first year students), and (b) judge their performance relatively accurately after the fact, students were unable to predict the percentage of questions they would answer correctly with a testing procedure in which they have had a substantial amount of feedback. Previous test score was a much better predictor of current test performance than were individuals' expectations.