Functional ear (a)symmetry in brainstem neural activity relevant to encoding of voice pitch: a precursor for hemispheric specialization?

Pitch processing is lateralized to the right hemisphere; linguistic pitch is further mediated by left cortical areas. This experiment investigates whether ear asymmetries vary in brainstem representation of pitch depending on linguistic status. Brainstem frequency-following responses (FFRs) were elicited by monaural stimulation of the left and right ear of 15 native speakers of Mandarin Chinese using two synthetic speech stimuli that differ in linguistic status of tone. One represented a native lexical tone (Tone 2: T2); the other, T2′, a nonnative variant in which the pitch contour was a mirror image of T2 with the same starting and ending frequencies. Two 40-ms portions of f₀ contours were selected in order to compare two regions (R1, early; R2 late) differing in pitch acceleration rate and perceptual saliency. In R2, linguistic status effects revealed that T2 exhibited a larger degree of FFR rightward ear asymmetry as reflected in f₀ amplitude relative to T2′. Relative to midline (ear asymmetry = 0), the only ear asymmetry reaching significance was that favoring left ear stimulation elicited by T2′. By left- and right-ear stimulation separately, FFRs elicited by T2 were larger than T2′ in the right ear only. Within T2′, FFRs elicited by the earlier region were larger than the later in both ears. Within T2, no significant differences in FFRS were observed between regions in either ear. Collectively, these findings support the idea that origins of cortical processing preferences for perceptually-salient portions of pitch are rooted in early, preattentive stages of processing in the brainstem.     

Biculturalism and Academic Achievement of African American High School Students

Biculturalism was examined as a factor that may positively affect the academic achievement of African American high school students, beyond cultural identity and self‐esteem. Hierarchical regression analyses determined that cultural identity and academic self‐esteem were important factors for academic achievement, but not biculturalism. Implications and future research are discussed. Se examinó el biculturalismo como un factor que puede afectar positivamente al rendimiento académico de los alumnos de educación secundaria Afroamericanos, más allá de la identidad cultural y la autoestima. Los análisis de regresión jerárquica determinaron que la identidad cultural y la autoestima académica fueron factores importantes para el rendimiento académico, pero no el biculturalismo. Se discutieron implicaciones e investigaciones futuras.     

In the zone: flow state and cognition in older adults

The current study investigated the nature of the flow state among older adults. Flow is a pleasurable experiential state that occurs during full-capacity engagement in which an individual is performing at a level that is matched with the demands of the task. Each participant completed a scale assessing dimensions of flow in a particular activity selected by the participant. More cognitively demanding activities elicited higher levels of flow for those with higher fluid ability, but lower levels of flow for those with lower fluid ability. This pattern was reversed for activities that were low in demand. Our data highlight the potential importance of considering motivational states such as flow in understanding cognitive optimization in adulthood.     

Understanding and philosophical methodology

According to Conceptualism, philosophy is an independent discipline that can be pursued from the armchair because philosophy seeks truths that can be discovered purely on the basis of our understanding of expressions and the concepts they express. In his recent book, The Philosophy of Philosophy, Timothy Williamson argues that while philosophy can indeed be pursued from the armchair, we should reject any form of Conceptualism. In this paper, we show that Williamson??s arguments against Conceptualism are not successful, and we sketch a way to understand understanding that shows that there is a clear sense in which we can indeed come to know the answers to (many) philosophical questions purely on the basis of understanding.     

Does Maladaptive Coping Mediate the Relationship Between Borderline Personality Traits and Reactive and Proactive Aggression?

The aim of this study was to identify associations between borderline personality (BP) traits and reactive and proactive aggression, and to compare the meditational effects of maladaptive coping in samples of older adolescents (n = 133) and young adults (n = 93), which has not hitherto been explored. This was a cross‐sectional study that used self‐report measures to assess BP traits on a continuum, trait‐based reactive and proactive aggression, and coping strategies. In adults, maladaptive emotional coping significantly mediated the relationship between BP and reactive aggression, and maladaptive avoidant coping mediated the relationship between BP and proactive aggression; no significant mediational effects were found for adolescents. These findings highlight potential explanations for associations between BP traits and reactive and proactive aggression in young adults, and indicate that reactive aggression in adult BPs could be decreased by reducing emotional coping, and proactive aggression by reducing avoidant coping. Aggr. Behav. 38:403‐413, 2012. © 2012 Wiley Periodicals, Inc.     

Eye gaze metrics reflect a shared motor representation for action observation and movement imagery

Action observation (AO) and movement imagery (MI) have been reported to share similar neural networks. This study investigated the congruency between AO and MI using the eye gaze metrics, dwell time and fixation number. A simple reach-grasp-place arm movement was observed and, in a second condition, imagined where the movement was presented from the first person perspective (1PP) and the third person perspective (3PP). Dwell time and number of fixations were calculated for whole scene and regions of interest (ROIs). For whole scene, no significant differences were found in the number of fixations for condition (AO, MI) or perspective. Dwell time, however, was significantly longer in AO than MI. For ROIs, the number of fixations was significantly greater in 1PP than 3PP. The data provide support for congruence between motor simulation states but also indicate some functional differences.     

Electrophysiological indices of emotion processing during retrieval of autobiographical memories by school-age children

We used event-related potentials (ERPs) to examine emotion processing during retrieval of emotional autobiographical memories by school-age children. We initiated processing of the emotional experiences using neutral cue words. On one-third of trials, children were instructed to think of a memory of a negative event, and on another third of trials, they were instructed to think of a memory of a positive event. We then recorded ERPs from 32 electrode sites as the children processed the emotional memories again later in the testing session. The 7- to 10-year-old children generated memories appropriate to the valences specified in the instructions. Neural responses differed as a function of the emotional valence of the events associated with the cues and as a function of gender. In the sample as a whole, differential processing of positive relative to negative and neutral emotions was apparent at posterior electrode sites 1,000–1,500 ms after stimulus onset. For girls, the effect was apparent beginning at 500 ms. No differences between the neural responses to negative and neutral stimuli were observed. At frontal electrode sites, girls evidenced faster processing of positive than of negative emotion, whereas boys evidenced faster processing of negative than of positive emotion. In conclusion, we discuss the possible origins of gender-differential patterns of neural processing.     

The role of numerical competence in a specialized predatory strategy of an araneophagic spider

Although a wide range of vertebrates have been considered in research on numerical competence, little is known about the role of number-related decisions in the predatory strategies of invertebrates. Here, we investigate how numerical competence is expressed in a highly specialized predatory strategy adopted by the small juveniles of Portia africana when practicing communal predation, with the prey being another spider, Oecobius amboseli. Two or more P. africana juveniles sometimes settle by the same oecobiid nest and then share the meal after one individual captures the oecobiid. Experiments were designed to clarify how these predators use number-related cues in conjunction with non-numerical cues when deciding whether to settle at a nest. We used lures (dead spiders positioned in lifelike posture) arranged in a series of 24 different scenes defined by the type, configuration and especially number of lures. On the whole, our findings suggest that P. africana juveniles base settling decisions on the specific number of already settled conspecific juveniles at the nest and express a preference for settling when the number is one instead of zero, two or three. By varying the size of the already settled juveniles and their positions around the nest, we show that factors related to continuous variables and stimulus configuration are unlikely explanations for our findings.