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Supplemental Digital Content is available in the text., Background: Stakeholder involvement in health care research has been shown to improve research development, processes, and dissemination. The literature is developing on stakeholder engagement methods and preliminarily validated tools for evaluating stakeholder level of engagement have been proposed for specific stakeholder groups and settings. Objectives: This paper describes the methodology for engaging a Study Advisory Committee (SAC) in research and reports on the use of a stakeholder engagement survey for measuring level of engagement. Methods: Stakeholders with previous research connections were recruited to the SAC during the planning process for a multicenter randomized control clinical trial, which is ongoing at the time of this writing. All SAC meetings undergo qualitative analysis, while the Stakeholder Engagement Survey instrument developed by the Patient-Centered Outcomes Research Institute (PCORI) is distributed annually for quantitative evaluation. Results: The trial’s SAC is composed of 18 members from 3 stakeholder groups: patients and their caregivers; patient advocacy organizations; and health care payers. After an initial in-person meeting, the SAC meets quarterly by telephone and annually in-person. The SAC monitors research progress and provides feedback on all study processes. The stakeholder engagement survey reveals improved engagement over time as well as continued challenges. Conclusions: Stakeholder engagement in the research process has meaningfully contributed to the study design, patient recruitment, and preliminary analysis of findings.

Influences from the visual (AEV), auditory (FAES), and somatosensory (SIV) divisions of the cat anterior ectosylvian sulcus (AES) play a critical role in rendering superior colliculus (SC) neurons capable of multisensory integration. However, it is not known whether this is accomplished via their independent sensory-specific action or via some cross-modal cooperative action that emerges as a consequence of their convergence on SC neurons. Using visual–auditory SC neurons as a model, we examined how selective and combined deactivation of FAES and AEV affected SC multisensory (visual–auditory) and unisensory (visual–visual) integration capabilities. As noted earlier, multisensory integration yielded SC responses that were significantly greater than those evoked by the most effective individual component stimulus. This multisensory “response enhancement” was more evident when the component stimuli were weakly effective. Conversely, unisensory integration was dominated by the lack of response enhancement. During cryogenic deactivation of FAES and/or AEV, the unisensory responses of SC neurons were only modestly affected; however, their multisensory response enhancement showed a significant downward shift and was eliminated. The shift was similar in magnitude for deactivation of either AES subregion and, in general, only marginally greater when both were deactivated simultaneously. These data reveal that SC multisensory integration is dependent on the cooperative action of distinct subsets of unisensory corticofugal afferents, afferents whose sensory combination matches the multisensory profile of their midbrain target neurons, and whose functional synergy is specific to rendering SC neurons capable of synthesizing information from those particular senses.

While research over the last 30 years has shown that sermons have a minimal influence on listeners, denominational differences in sermon effectiveness have been unexplored. We surveyed Anglican and Elim members (representing Mainline and Pentecostal Christians respectively) to compare their responses to sermons, and the sermon features and themes they prefer. The results revealed higher sermon effectiveness responses from Elim participants. The data also showed that Anglicans desired significant intellectual content and discussion of social issues compared with Elim members who gave higher ratings on almost all other features and themes. However, participants from both churches responded to sermons in a predominantly emotional (rather than cognitive or behavioural) way, and most wanted to hear sermons on grace and forgiveness. We conclude by noting the need for evaluations of sermon effectiveness that reflect preachers' and listeners' motivations.

The spatial register of the different receptive fields of multisensory neurons in the superior colliculus (SC) plays a significant role in determining the responses of these neurons to cross-modal stimulus combinations. Spatially coincident visual-auditory stimuli fall within these overlapping receptive fields and generally produce response enhancements that exceed the individual modality-specific responses and can exceed their sum. Yet, in this context, it has not been clear how "spatial coincidence" is operationally defined. Given the large size of SC receptive fields, visual and auditory stimuli could be within their respective receptive fields even when there are substantial spatial disparities between them. Indeed, previous observations have raised the possibility that there may be a second level of determinism in how SC neurons deal with the relative spatial locations of within-field cross-modal stimuli; specifically, that multisensory response enhancements become progressively weaker as the within-field visual and auditory stimuli become increasingly disparate. While the present experiments demonstrated that SC multisensory neurons have heterogeneous receptive fields, and that the greatest number of impulses evoked were by stimuli that fell within the area of cross-modal receptive field overlap, they also indicate that there is no systematic relationship between cross-modal stimulus disparity and the magnitude of multisensory response enhancement. Thus, two within-field cross-modal stimuli produced the same proportionate change (i.e., multisensory response enhancement) when they were widely disparate as they did when they overlapped one another in space. These observations indicate that cross-modal spatial coincidence can be defined operationally by the borders of an SC neuron's receptive fields regardless of the size of those receptive fields and/or the absolute spatial disparity between within-field cross-modal stimuli.

Kadunce, Daniel C., J. William Vaughan, Mark T. Wallace, Gyorgy Benedek, and Barry E. Stein. Mechanisms of within- and cross-modality suppression in the superior colliculus. J. Neurophysiol. 78: 2834–2847, 1997. The present studies were initiated to explore the basis for the response suppression that occurs in cat superior colliculus (SC) neurons when two spatially disparate stimuli are presented simultaneously or in close temporal proximity to one another. Of specific interest was examining the possibility that suppressive regions border the receptive fields (RFs) of unimodal and multisensory SC neurons and, when activated, degrade the neuron's responses to excitatory stimuli. Both within- and cross-modality effects were examined. An example of the former is when a response to a visual stimulus within its RF is suppressed by a second visual stimulus outside the RF. An example of the latter is when the response to a visual stimulus within the visual RF is suppressed when a stimulus from a different modality (e.g., auditory) is presented outside its (i.e., auditory) RF. Suppressive regions were found bordering visual, auditory, and somatosensory RFs. Despite significant modality-specific differences in the incidence and effectiveness of these regions, they were generally quite potent regardless of the modality. In the vast majority (85%) of cases, responses to the excitatory stimulus were degraded by ≥50% by simultaneously stimulating the suppressive region. Contrary to expectations and previous speculations, the effects of activating these suppressive regions often were quite specific. Thus powerful within-modality suppression could be demonstrated in many multisensory neurons in which cross-modality suppression could not be generated. However, the converse was not true. If an extra-RF stimulus inhibited center responses to stimuli of a different modality, it also would suppress center responses to stimuli of its own modality. Thus when cross-modality suppression was demonstrated, it was always accompanied by within-modality suppression. These observations suggest that separate mechanisms underlie within- and cross-modality suppression in the SC. Because some modality-specific tectopetal structures contain neurons with suppressive regions bordering their RFs, the within-modality suppression observed in the SC simply may reflect interactions taking place at the level of one input channel. However, the presence of modality-specific suppression at the level of one input channel would have no effect on the excitation initiated via another input channel. Given the modality-specificity of tectopetal inputs, it appears that cross-modality interactions require the convergence of two or more modality-specific inputs onto the same SC neuron and that the expression of these interactions depends on the internal circuitry of the SC. This allows a cross-modality suppressive signal to be nonspecific and to degrade any and all of the neuron's excitatory inputs.

It has recently been demonstrated that the maturation of normal multisensory circuits in the cortex of the cat takes place over an extended period of postnatal life. Such a finding suggests that the sensory experiences received during this time may play an important role in this developmental process. To test the necessity of sensory experience for normal cortical multisensory development, cats were raised in the absence of visual experience from birth until adulthood, effectively precluding all visual and visual–nonvisual multisensory experiences. As adults, semichronic single-unit recording experiments targeting the anterior ectosylvian sulcus (AES), a well-defined multisensory cortical area in the cat, were initiated and continued at weekly intervals in anesthetized animals. Despite having very little impact on the overall sensory representations in AES, dark-rearing had a substantial impact on the integrative capabilities of multisensory AES neurons. A significant increase was seen in the proportion of multisensory neurons that were modulated by, rather than driven by, a second sensory modality. More important, perhaps, there was a dramatic shift in the percentage of these modulated neurons in which the pairing of weakly effective and spatially and temporally coincident stimuli resulted in response depressions. In normally reared animals such combinations typically give rise to robust response enhancements. These results illustrate the important role sensory experience plays in shaping the development of mature multisensory cortical circuits and suggest that dark-rearing shifts the relative balance of excitation and inhibition in these circuits.

The present study suggests that the neural computations used to integrate information from different senses are distinct from those used to integrate information from within the same sense. Using superior colliculus neurons as a model, it was found that multisensory integration of cross-modal stimulus combinations yielded responses that were significantly greater than those evoked by the best component stimulus. In contrast, unisensory integration of within-modal stimulus pairs yielded responses that were similar to or less than those evoked by the best component stimulus. This difference is exemplified by the disproportionate representations of superadditive responses during multisensory integration and the predominance of subadditive responses during unisensory integration. These observations suggest that different rules have evolved for integrating sensory information, one (unisensory) reflecting the inherent characteristics of the individual sense and, the other (multisensory), unique supramodal characteristics designed to enhance the salience of the initiating event.

Although there are many perceptual theories that posit particular maturational profiles in higher-order (i.e., cortical) multisensory regions, our knowledge of multisensory development is primarily derived from studies of a midbrain structure, the superior colliculus. Therefore, the present study examined the maturation of multisensory processes in an area of cat association cortex [i.e., the anterior ectosylvian sulcus (AES)] and found that these processes are rudimentary during early postnatal life and develop only gradually thereafter. The AES comprises separate visual, auditory, and somatosensory regions, along with many multisensory neurons at the intervening borders between them. During early life, sensory responsiveness in AES appears in an orderly sequence. Somatosensory neurons are present at 4 weeks of age and are followed by auditory and multisensory (somatosensory–auditory) neurons. Visual neurons and visually responsive multisensory neurons are first seen at 12 weeks of age. The earliest multisensory neurons are strikingly immature, lacking the ability to synthesize the cross-modal information they receive. With postnatal development, multisensory integrative capacity matures. The delayed maturation of multisensory neurons and multisensory integration in AES suggests that the higher-order processes dependent on these circuits appear comparatively late in ontogeny.

Many neurons in the superior colliculus (SC) integrate sensory information from multiple modalities, giving rise to significant response enhancements. Although enhanced multisensory responses have been shown to depend on the spatial and temporal relationships of the stimuli as well as on their relative effectiveness, these factors alone do not appear sufficient to account for the substantial heterogeneity in the magnitude of the multisensory products that have been observed. Toward this end, the present experiments have revealed that there are substantial differences in the operations used by different multisensory SC neurons to integrate their cross-modal inputs, suggesting that intrinsic differences in these neurons may also play an important deterministic role in multisensory integration. In addition, the integrative operation employed by a given neuron was found to be well correlated with the neuron's dynamic range. In total, four categories of SC neurons were identified based on how their multisensory responses changed relative to the predicted addition of the two unisensory inputs as stimulus effectiveness was altered. Despite the presence of these categories, a general rule was that the most robust multisensory enhancements were seen with combinations of the least effective unisensory stimuli. Together, these results provide a better quantitative picture of the integrative operations performed by multisensory SC neurons and suggest mechanistic differences in the way in which these neurons synthesize cross-modal information.

Multisensory neurons in the superior colliculus (SC) typically respond to combinations of stimuli from multiple modalities with enhancements and/or depressions in their activity. Although such changes in response have been shown to follow a predictive set of integrative principles, these principles fail to completely account for the full range of interactions seen throughout the SC population. In an effort to better define this variability, we sought to determine if there were additional features of the neuronal response profile that were predictive of the magnitude of the multisensory interaction. To do this, we recorded from 109 visual-auditory SC neurons while systematically manipulating stimulus intensity. Along with the previously described roles of space, time, and stimulus effectiveness, two features of a neuron's response profile were found to offer predictive value as to the magnitude of the multisensory interaction: spontaneous activity and the level of sensory responsiveness. Multisensory neurons with little or no spontaneous activity and weak sensory responses had the capacity to exhibit large response enhancements. Conversely, neurons with modest spontaneous activity and robust sensory responses exhibited relatively small response enhancements. Together, these results provide a better view into multisensory integration, and suggest substantial heterogeneity in the integrative characteristics of the multisensory SC population.

In their analysis of disorder and discrimination (“Coping with chaos: How disordered contexts promote stereotyping and discrimination,” Reports, 8 April, p. 251), D. A. Stapel and S. Lindenberg find that a disordered environment promotes more discrimination than one that is clean and ordered. Unfortunately, their design precludes this conclusion. Part of the study involved subjects (all Caucasian) choosing one seat among six, with the first seat occupied by a confederate (either a white person or a black person). In the ordered condition, the distance between the seat chosen and the confederate was unaffected by the race of the confederate, whereas in the disordered condition, the distance was greater if the confederate was black than if he was white. Although the authors were careful to balance the sexes of the subjects (half female, half male), they did not balance the races of the subjects (all Caucasian). Their conclusion, that disorder affects stereotyping, only holds if results from the neglected populations (e.g., blacks) are irrelevant. The unexamined conditions are not irrelevant. Suppose blacks sat farther from blacks than whites under the disordered condition (just as the whites did). This would bring the entire conclusion into question. Suppose they sat farther from whites than blacks in the disordered condition. This would support the conclusion, but show that stereotyping is not a white-only phenomenon. Suppose they sat farther from whites in the ordered condition than in the disordered condition. This would suggest disorder increases stereotyping by whites that and that order increases stereotyping by blacks, and therefore vitiate their policy recommendations: “One way to fight unwanted stereotyping and discrimination is to diagnose environmental disorder early and to intervene immediately by cleaning up and creating physical order” (p. 253).

The majority of multisensory neurons in the cat superior colliculus (SC) are able to synthesize cross-modal cues (e.g., visual and auditory) and thereby produce responses greater than those elicited by the most effective single modality stimulus and, sometimes, greater than those predicted by the arithmetic sum of their modality-specific responses. The present study examined the role of corticotectal inputs from two cortical areas, the anterior ectosylvian sulcus (AES) and the rostral aspect of the lateral suprasylvian sulcus (rLS), in producing these response enhancements. This was accomplished by evaluating the multisensory properties of individual SC neurons during reversible deactivation of these cortices individually and in combination using cryogenic deactivation techniques. Cortical deactivation eliminated the characteristic multisensory response enhancement of nearly all SC neurons but generally had little or no effect on a neuron's modality-specific responses. Thus, the responses of SC neurons to combinations of cross-modal stimuli were now no different from those evoked by one or the other of these stimuli individually. Of the two cortical areas, AES had a much greater impact on SC multisensory integrative processes, with nearly half the SC neurons sampled dependent on it alone. In contrast, only a small number of SC neurons depended solely on rLS. However, most SC neurons exhibited dual dependencies, and their multisensory enhancement was mediated by either synergistic or redundant influences from AES and rLS. Corticotectal synergy was evident when deactivating either cortical area compromised the multisensory enhancement of an SC neuron, whereas corticotectal redundancy was evident when deactivation of both cortical areas was required to produce this effect. The results suggest that, although multisensory SC neurons can be created as a consequence of a variety of converging tectopetal afferents that are derived from a host of subcortical and cortical structures, the ability to synthesize cross-modal inputs, and thereby produce an enhanced multisensory response, requires functional inputs from the AES, the rLS, or both.

Analyses of free-operant choice usually employ one of two general procedures: the simple concurrent procedure (i.e., a concurrent variable-interval variable-interval schedule) or the concurrent-chains procedure (i.e., concurrently available initial links, each leading to an exclusively available terminal link). Theories about choice usually focus on only one of the two procedures. For example, maximization theories, which assert that behavior is distributed between two alternatives in such a way that overall rate of reinforcement is maximized, have been applied only to the simple concurrent procedure. In the present paper, a form of the pairing hypothesis (according to which pairings between one stimulus and another affect the value of the first, and pairings between responses and reinforcers affect the value of the former) is developed in a way that allows it to make qualitative predictions with regard to choice in a variety of simple concurrent and concurrent-chains procedures. The predictions include matching on concurrent variable-interval variable-interval schedules, preference reversal in the self-control paradigm, and preference for tandem over chained terminal links.

In a discrete-trials procedure, pigeons chose between a fixed-ratio 81 schedule and a progressive-ratio schedule by making a single peck at the key correlated with one or the other of these schedules. The response requirement on the progressive-ratio schedule began at 1 and increased by 10 each time the progressive-ratio schedule was chosen. Each time the fixed-ratio schedule was chosen, the requirement on the progressive-ratio schedule was reset to 1 response. In conditions where there was no intertrial interval, subjects chose the progressive-ratio schedule for an average of about five consecutive trials (during which the response requirement increased to 41), and then chose the fixed-ratio schedule. This ratio was larger than that predicted by an optimality analysis that assumes that subjects respond in a pattern that minimizes the response-reinforcer ratio or one that assumes that subjects respond in a pattern that maximizes the overall rate of reinforcement. In conditions with a 25-s or 50-s intertrial interval, subjects chose the progressive-ratio schedule for an average of about eight consecutive trials before choosing the fixed-ratio schedule. This change in performance with the addition of an intertrial interval was also not predicted by an optimality analysis. On the other hand, the results were consistent with the theory that choice is determined by the delays to the reinforcers delivered on the present trial and on subsequent trials.

Pigeons were run in both single-key and concurrent-key experiments in which, over most of the range of response rates, an increase in response rate gave rise to a continuous decrease in reinforcement rate. In spite of the fact that a low response rate would have produced a high reinforcement rate, all birds responded at relatively high rates, thus keeping reinforcement rates substantially below the maximum possible. In the concurrent-key experiment, in addition to responding at relatively high rates, the birds' ratios of responses approximately matched the corresponding ratios of obtained reinforcers. The results are inconsistent with most theories of optimal performance, which assume that organisms behave in ways that either maximize reinforcement value or minimize deviations from a free-behavior point. On the other hand, the results are consistent with the assumption that reinforcement strengthens the tendency to respond.