Lateralization of narrow-band noise by blind and sighted listeners

The effects of varying interaural time delay (ITD) and interaural intensity difference (IID) were measured in normal-hearing sighted and congenitally blind subjects as a function of eleven frequencies and at sound pressure levels of 70 and 90 dB, and at a sensation level of 25 dB (sensation level refers to the pressure level of the sound above its threshold for the individual subject). Using an 'acoustic' pointing paradigm, the subject varied the IID of a 500 Hz narrow-band (100 Hz) noise (the 'pointer') to coincide with the apparent lateral position of a 'target' ITD stimulus. ITDs of 0, +/-200, and +/-400 micros were obtained through total waveform delays of narrow-band noise, including envelope and fine structure. For both groups, the results of this experiment confirm the traditional view of binaural hearing for like stimuli: non-zero ITDs produce little perceived lateral displacement away from 0 IID at frequencies above 1250 Hz. To the extent that greater magnitude of lateralization for a given ITD, presentation level, and center frequency can be equated with superior localization abilities, blind listeners appear at least comparable and even somewhat better than sighted subjects, especially when attending to signals in the periphery. The present findings suggest that blind listeners are fully able to utilize the cues for spatial hearing, and that vision is not a mandatory prerequisite for the calibration of human spatial hearing.     

Aging and rule learning: the case of the multiplicative law

This work examined the effect of age on the ability to learn multiplicative combination rules. Participants learned the multiplicative relationship between daily tobacco intake, daily alcohol intake, and risk of esophageal cancer. The hypothesis was that younger adults would learn to implement a multiplicative combination rule and older adults would not, despite feedback. Among the younger adults, complete rule learning took place. Before receiving feedback, they used an underadditive rule, a result consistent with previous studies. After only a limited amount of feedback, they learned to use a multiplicative rule. Even after receiving feedback, however, the older adults still showed difficulties in using the multiplicative rule. These results strengthen the proposition by Chasseigne, Mullet, and Stewart (1997) that the differences between younger and older adults in function learning are related mainly to flexibility of functioning.     

Visual habituation at five months: short-term reliability of measures obtained with a new polynomial regression criterion

Using a new polynomial regression criterion, the authors investigated empirically the short-term reliability of infants' visual habituation measures. Twenty-one 5-month-old infants were tested twice with a 1-day interval. Results revealed many reliable habituation measures, a reliable reaction to novelty measure, and a new reliable measure of interest. The 2nd-order polynomial regression criterion probably produced this improvement because it uses all of the available looking time data.     

Sleep-dependent hippocampal slow activity correlates with waking memory performance in humans

The positive effect of postlearning sleep on memory consolidation as well as the relationship between sleep-related memory processes and the hippocampal formation are increasingly clarified topics in neurobiology. However, the possibility of a stable relationship between waking mnemonic performance and sleep-dependent hippocampal electric activity is unexplored. Here we report a correlative analysis between sleep-dependent parahippocampal-hippocampal (pHip-Hip) electric activity recorded by foramen ovale (FO) electrodes and different types of memory performances in epileptic patients. Psychological testing was performed days or weeks before electrophysiological recordings. The relative spectral power of the slow activity (below 1.25 Hz) during deep non-REM (NREM) sleep at the right pHip-Hip region correlated positively with the visual memory performance according to Rey-Osterrieth Complex Figure Test (ROCFT). Along the posterior-anterior direction of the hippocampal formation a linear increasing of correlations was observed. The relative power of the activity below 1.25 Hz at the left pHip-Hip during phasic REM sleep correlated positively with verbal learning performance and mnemonic retention values according to ROCFT. It is concluded that the pHip-Hip structures' capacity of producing high amplitude and synchronized slow (< 1 Hz) oscillation during deep NREM sleep is related to the functional power of these structures. We hypothesize that the asymmetric (side-specific) propagation of ponto-geniculo-occipital (PGO) activity to the pHip-Hip region is related to the memory correlates of phasic REM sleep.     

Identity construction and career development interventions with emerging adults

Today's wealthy societies are more fluid, varied and complex than they were just a few decades ago. As a consequence, what were “vocational choices” at the beginning of the 20th century now appear as “life designing issues”. In this context, contemporary research stresses the plurality and relative malleability of human subjects as well as their ability to take reflexive stances on their current and past experiences. Fitting in such an epistemology, a self-constructing model is proposed as a basis for a life designing counseling interview. This model describes self-identity as a dynamic system of (past, present and expected) subjective identity forms (SIF), the synthesis and dynamism of which originate in a tension between two kinds of reflexivity. Counseling interviews with emerging adults show that the elicitation of some expected SIF allows them to re-read their current and past experiences from such a perspective and constitutes a compelling incentive to act.     

Safety behavior can hamper the extinction of fear of movement-related pain: An experimental investigation in healthy participants

Excessive fear of movement-related pain (FMRP), and its associated avoidance behavior, is considered a major risk factor for disability in chronic musculoskeletal pain. The current study aimed to investigate whether engaging in safety behavior, conceptualized as an avoidance response, hampers the extinction of FMRP. In a differential conditioning paradigm, we used joystick movements as conditioned stimuli (CSs) and a painful electrocutaneous stimulus as the unconditioned stimulus (US). In the Safety group, participants received the opportunity to avoid the pain-US by pressing a safety button during the extinction phase, whereas in the Control group, this option was not included. In a subsequent test phase, this safety button was no longer available. In two experiments, results demonstrate successful acquisition and extinction. Retrospective FMRP ratings in both experiments revealed a return of fear of pain in the test phase in the Safety group, but not in the Control group. In Experiment 1, mean eyeblink startle reflex amplitudes partly corroborated the self-report findings on fear of pain. The present results suggest that performing safety behavior during cognitive-behavioral interventions, i.e., exposure, might increase the risk of a return of FMRP.     

When local processing increases the appeal of healthy options

People often encounter self-control challenges in complex everyday environments in which objects that promote a given goal (e.g., to eat healthily) are mixed together with objects that obstruct that goal. For example, healthy and unhealthy food choices are often mixed together in restaurant menus. Because local processing facilitates attention to low-level details, we expect that it may play an important role in these complex situations. In the present studies, we test the hypothesis that local processing supports self-control when goal items and temptations are contextually paired. As predicted, our findings revealed that local processing (relative to global processing) increased evaluations of healthy items when those items were presented together with unhealthy items. As hypothesized, this effect of local processing only occurred when healthy and unhealthy foods were presented as complementary – not competing – options, suggesting that local processing may increase evaluations of healthy options by decreasing the extent to which individuals accept environmental cues that healthy and unhealthy foods belong together. These findings support recent research demonstrating that despite strong evidence of the advantages of global processing for self-control, local processing may also support self-control efforts in some important everyday situations.     

Looking at the actor's face: Identity cues and attentional focus in false memories of action performance from observation

Observing another's actions can induce false memories of self-performance. We investigated whether such observation inflation depends on the discriminability between the self and the observed actor. Discriminability was manipulated by presenting actions either with or without a key visual identity cue, i.e., the actor's face. We also examined whether self–other confusions in the face-visible condition depend on attentional focus (directed to the observed action vs. the actor's face). In the action-only condition, observation inflation was significant and greater than in the face-visible conditions, in which the effect was moderated by attentional focus: It persisted under an action focus but was eliminated under a face focus. Findings for correct memories of self-performance suggest that the reduced effect is not merely due to weaker encoding of the actions themselves. We conclude that self–other confusions in action memory are constrained by the availability of distinctive non-self cues during observation, and sustained by a visual focus on observed actions.     

Congruent visual information improves traffic signage

In the last five decades, cognitive scientists and the psychologists of reasoning have dedicated a lot of effort designing usable traffic signs. This study investigated the interference effect produced by the position of the sign elements in traffic signage on response accuracy and reaction time. Sixteen drivers performed a flanker interference reaction time task. Incongruent graphical/space solutions, actually used for the airport stack-type sign, lead to increased reaction time and a reduction in the proportion of correct answers. These results suggest that incongruent visual information should be avoided, as this might impair drivers’ performance. These findings provide important information for the specification of future signage design guidelines and for improving road safety.