Engaging with research ethics in central Francophone Africa: reflections on a workshop about ancillary care

ABSTRACT: Research ethics is predominantly taught and practiced in Anglophone countries, particularly those in North America and Western Europe. Initiatives to build research ethics capacity in developing countries must attempt to avoid imposing foreign frameworks and engage with ethical issues in research that are locally relevant. This article describes the process and outcomes of a capacity-building workshop that took place in Kinshasa, Democratic Republic of Congo in the summer of 2011. Although the workshop focused on a specific ethical theme - the responsibilities of researchers to provide health-related care to their research participants - we argue that the structure of the workshop offers a useful method for engaging with research ethics in general, and the theme of ancillary care encourages a broad perspective on research ethics that is highly pertinent in low-income countries. The workshop follows an interactive, locally driven model that could be fruitfully replicated in similar settings.     

Parafoveal processing in reading

The present review summarizes research investigating how words are identified parafoveally (and foveally) in reading. Parafoveal and foveal processing are compared when no other concurrent task is required (e.g., in single-word recognition tasks) and when both are required simultaneously (e.g., during reading). We first review methodologies used to study parafoveal processing (e.g., corpus analyses and experimental manipulations, including gaze-contingent display change experiments such as the boundary, moving window, moving mask, and fast priming paradigms). We then turn to a discussion of the levels of representation at which words are processed (e.g., orthographic, phonological, morphological, lexical, syntactic, and semantic). Next, we review relevant research regarding parafoveal processing, summarizing the extent to which words are processed at each of those levels of representation. We then review some of the most controversial aspects of parafoveal processing, as they relate to reading: (1) word skipping, (2) parafoveal-on-foveal effects, and (3) n + 1 and n + 2 preview benefit effects. Finally, we summarize two of the most advanced models of eye movements during reading and how they address foveal and parafoveal processing.     

Observers can voluntarily shift their psychometric functions without losing sensitivity

Psychometric sensory discrimination functions are usually modeled by cumulative Gaussian functions with just two parameters, their central tendency (μ) and their slope (1/σ). These correspond to Fechner's "constant" and "variable" errors, respectively. Fechner pointed out that even the constant error could vary over space and time and could masquerade as variable error. We wondered whether observers could deliberately introduce a constant error into their performance without loss of precision. In three-dot vernier and bisection tasks with the method of single stimuli, observers were instructed to favour one of the two responses when unsure of their answer. The slope of the resulting psychometric function was not significantly changed, despite a significant change in central tendency. Similar results were obtained when altered feedback was used to induce bias. We inferred that observers can adopt artificial response criteria without any significant increase in criterion fluctuation. These findings have implications for some studies that have measured perceptual "illusions" by shifts in the psychometric functions of sophisticated observers.     

Magnitude of force perception errors during static contractions of the knee extensors in healthy young and elderly individuals

The accuracy of force perception during muscular contraction has not been studied extensively, despite its importance in rehabilitation and training. The purpose of this study was to quantify the errors made by healthy young and elderly individuals in their perceptions of force produced at the knee. Four different tasks were used to evaluate the perception of force and the effect of a sensory-motor reference and simultaneous contraction on the accuracy of perception. The absolute errors were similar between groups, with values of 11.9% to 16.3%, depending on the task. The raw perception errors were greater for high levels of force (>50% of the maximal voluntary contraction, or MVC), indicating an overestimation of the forces produced for both groups. At 70% MVC, the sensory-motor reference reduced raw perception errors, and the simultaneous contraction improved the accuracy of force production. Healthy young and elderly individuals had about the same capacity to judge the muscular force of their knee extensors. Therapists involved in the training of active?elderly?individuals should be aware that the accuracy of force perception is not perfect and that these clients have the same ability as young individuals to perceive their knee extension strength.     

Time-course of hemispheric preference for processing contralateral relevant shapes: P1pc, N1pc, N2pc, N3pc

A most sensitive and specific electrophysiological indicator of selective processing of visual stimuli is the N2pc component. N2pc is a negative EEG potential peaking 250 ms after stimulus onset, recorded from posterior sites contralateral to relevant stimuli. Additional deflections preceding or following N2pc have been obtained in previous studies, possibly produced by specific stimulus features or specific prime-target sequences. To clarify the entire time-course of the contralateral- ipsilateral (C-I) difference recorded from the scalp above visual cortex in response to left-right pairs of targets and distracters, C-I differences were here compared between two types of stimuli and between stimuli that were or were not preceded by masked neutral primes. The C-I difference waveform consisted of several peaks, termed here P1pc (60-100 ms after target onset), N1pc (120-160 ms), N2pc (220-280 ms), and N3pc (360-400 ms). Being markedly enhanced when stimuli were preceded by the neutral primes, P1pc may indicate a response to stimulus change. Also, when stimuli were primed, N2pc reached its peak earlier, thereby tending to merge with N1pc. N3pc seemed to increase when target discrimination was difficult. N1pc, N2pc, and N3pc appear as three periods of one process. N3pc probably corresponds to L400 or SPCN as described in other studies. These observations suggest that the neurophysiological basis of stimulus-driven focusing of attention on target stimuli is a process that lasts for hundreds of milliseconds, with the relevant hemisphere being activated in an oscillating manner as long as required by the task.     

RSVP in orbit: Identification of single and dual targets in motion

Three experiments using rapid serial visual presentation (RSVP) tested participants' ability to detect targets in streams that are in motion. These experiments compared the ability to identify moving versus stationary RSVP targets and examined the attentional blink with pairs of targets that were moving or stationary. One condition presented RSVP streams in the center of the screen; a second condition used an RSVP that was orbiting in a circle, with participants instructed to follow the stream with their eyes; and a third condition had participants fixate in the middle while observing a circling RSVP stream. Relative to performance in stationary RSVP streams, participants were not markedly impaired in detecting single targets in RSVP streams that were moving, either with or without instructions to pursue the motion. In streams with two targets, a normal attentional blink effect was observed when participants were instructed to pursue the moving stream. When participants had to maintain central fixation as the RSVP stream moved, the attentional blink was nearly absent even when a trailing mask was added. We suggest that the reduction of the attentional blink for moving RSVP streams may reflect a reduced ability to perceive the temporal boundaries of the individual items.     

The speed of recognition of personally familiar faces

Despite the generally accepted notion that humans are very good and fast at recognising familiar individuals from their faces, the actual speed with which this fundamental brain function can be achieved remains largely unknown. Here, two groups of participants were required to respond by finger-lift when presented with either a photograph of a personally familiar face (classmate), or an unfamiliar one. This speeded manual go/no-go categorisation task revealed that personally familiar faces could be categorised as early as 380 ms after presentation, about 80 ms faster than unfamiliar faces. When response times were averaged across all 8 stimulus presentations, we found that minimum RTs for both familiar and unfamiliar face decisions were substantially lower (310 ms and 370 ms). Analyses confirmed that stimulus repetition enhanced the speed with which faces were categorised, irrespective of familiarity, and that repetition did not affect the observed benefit in RTS for familiar over unfamiliar faces. These data, representing the elapsed time from stimulus onset to motor output, put constraints on the time course of familiar face recognition in the human brain, which can be tracked more precisely by high temporal resolution electrophysiological measures.     

Retrieval during learning facilitates subsequent memory encoding

In multiple-list learning, retrieval during learning has been suggested to improve recall of the single lists by enhancing list discrimination and, at test, reducing interference. Using electrophysiological, oscillatory measures of brain activity, we examined to what extent retrieval during learning facilitates list encoding. Subjects studied 5 lists of items in anticipation of a final cumulative recall test and did either a retrieval or a no-retrieval task between study of the lists. Retrieval was from episodic memory (recall of the previous list), semantic memory (generation of exemplars from an unrelated category), or short-term memory (2-back task). Behaviorally, all 3 forms of retrieval enhanced recall of both previously and subsequently studied lists. Physiologically, the results showed an increase of alpha power (8-14 Hz) from List 1 to List 5 encoding when no retrieval activities were interpolated but no such increase when any of the 3 retrieval activities occurred. Brain-behavior correlations showed that alpha-power dynamics from List 1 to List 5 encoding predicted subsequent recall performance. The results suggest that, without intermittent retrieval, encoding becomes ineffective across lists. In contrast, with intermittent retrieval, there is a reset of the encoding process for each single list that makes encoding of later lists as effective as encoding of early lists.     

The taste of music

Zarlino, one of the most important music theorists of the XVI century, described the minor consonances as 'sweet' (dolci) and 'soft' (soavi) (Zarlino 1558/1983, in On the Modes New Haven, CT: Yale University Press, 1983). Hector Berlioz, in his Treatise on Modern Instrumentation and Orchestration (London: Novello, 1855), speaks about the 'small acid-sweet voice' of the oboe. In line with this tradition of describing musical concepts in terms of taste words, recent empirical studies have found reliable associations between taste perception and low-level sound and musical parameters, like pitch and phonetic features. Here we investigated whether taste words elicited consistent musical representations by asking trained musicians to improvise on the basis of the four canonical taste words: sweet, sour, bitter, and salty. Our results showed that, even in free improvisation, taste words elicited very reliable and consistent musical patterns:'bitter' improvisations are low-pitched and legato (without interruption between notes), 'salty' improvisations are staccato (notes sharply detached from each other), 'sour' improvisations are high-pitched and dissonant, and 'sweet' improvisations are consonant, slow, and soft. Interestingly, projections of the improvisations of taste words to musical space (a vector space defined by relevant musical parameters) revealed that, in musical space, improvisations based on different taste words were nearly orthogonal or opposite. Decoding methods could classify binary choices of improvisations (i.e., identify the improvisation word from the melody) at performance of around 80%--well above chance. In a second experiment we investigated the mapping from perception of music to taste words. Fifty-seven non-musical experts listened to a fraction of the improvisations. We found that listeners classified with high performance the taste word which had elicited the improvisation. Our results, furthermore, show that associations of taste and music go beyond basic sensory attributes into the domain of semantics, and open a new venue of investigation to understand the origins of these consistent taste-musical patterns.     

Race and gender of faces can be ignored

Past research indicates that faces can be more difficult to ignore than other types of stimuli. Given the important social and biological relevance of race and gender, the present study examined whether the processing of these facial characteristics is mandatory. Both unfamiliar and famous faces were assessed. Participants made speeded judgments about either the race (Experiment 1) or gender (Experiments 2–4) of a target name under varying levels of perceptual load, while ignoring a flanking distractor face that was either congruent or incongruent with the race/gender of the target name. In general, distractor–target congruency effects emerged when the perceptual load of the relevant task was low but not when the load was high, regardless of whether the distractor face was unfamiliar or famous. These findings suggest that face processing is not necessarily mandatory, and some aspects of faces can be ignored.