Maze navigation by honeybees: learning path regularity

We investigated the ability of honeybees to learn mazes of four types: constant-turn mazes, in which the appropriate turn is always in the same direction in each decision chamber; zig-zag mazes, in which the appropriate turn is alternately left and right in successive decision chambers; irregular mazes, in which there is no readily apparent pattern to the turns; and variable irregular mazes, in which the bees were trained to learn several irregular mazes simultaneously. The bees were able to learn to navigate all four types of maze. Performance was best in the constant-turn mazes, somewhat poorer in the zig-zag mazes, poorer still in the irregular mazes, and poorest in the variable irregular mazes. These results demonstrate that bees do not navigate such mazes simply by memorizing the entire sequence of appropriate turns. Rather, performance in the various configurations depends on the existence of regularity in the structure of the maze and on the ease with which this regularity is recognized and learned.     

Familiarity and pronounceability of nouns and names

Ratings of familiarity and pronounceability were obtained from a random sample of 199 surnames (selected from over 80,000 entries in the Purdue University phone book) and 199 nouns (from the Ku?era-Francis, 1967, word database). The distributions of ratings for nouns versus names are substantially different: Nouns were rated as more familiar and easier to pronounce than surnames. Frequency and familiarity were more closely related in the proper name pool than the word pool, although both correlations were modest. Ratings of familiarity and pronounceability were highly related for both groups. A production experiment showed that rated pronounceability was highly related to the time taken to produce a name. These data confirm the common belief that there are differences in the statistical and distributional properties of words as compared to proper names. The value of using frequency and the ratings of familiarity and pronounceability for predicting variations in actual pronunciations of words and names are discussed.     

Blame Game Triangulation between Parents,Teachers and Children with Academic Problems

This cross-sectional survey on a sample of parent, teacher and child respondents (n = 195) elicited their perceptions on or about the ‘reasons/causes’ for academic problems in school students. A semi-structured ‘Demographic Data Sheet’ and another open ended exploratory ‘Causes of Academic Problems Interview Schedule’ (CAPIS) exclusively developed for this study was used. A classification of the ‘causes’ for academic problems into four categories by two independent observers revealed preponderance of ‘child-centered’ causes (N: 937), followed by ‘teacher-centered’ causes (N: 751), ‘parent-centered’ (N: 643) and ‘environment centered’ causes (N: 362). Analysis of trends show significant statistical differences in reported perceptions between the three respondents (p: < 0.04); with highest disparity between ‘teacher-centered’ causative perceptions (p: < 0.001). Concordance rates as measured by Cohen’s Kappa Coefficient is reflected by greater agreements on or about the reasons for academic problems between parent-teacher respondents (0.34) and least for child-teacher reports (−0.08). The results suggest an attitudinal triangulation on or about the reasons attributed for academic problems between parents, teachers and the children. This opens up the need for stepping up measures to de-triangulate or harmonize these varying inter personal perceptions for optimum benefit of such children.     

Emotional and hemispheric asymmetries in shifts of attention: an ERP study

Inhibition of return (IOR) refers to the larger response time to cued targets appearing at long cue-to-target intervals. Given emotion-attention interactions and associated visual field (VF) asymmetries, we examined the effects of emotions and hemispheric processing on object- and location-based IOR. We expected reduced IOR and right hemispheric bias accompanied by differences in event-related potentials (ERPs) including lack of suppression of cued N1 and enhancement of Nd components for sad targets. Reaction times and ERPs were recorded in an exogenous cuing detection task using happy and sad schematic faces. Results revealed reduced IOR for left compared to right VF with sad faces but no such asymmetry for happy faces. Cued N1 amplitudes were suppressed for happy targets but not for sad targets presented to the left VF. Nd amplitudes were enhanced for right-hemispheric sad faces especially with object-based IOR. The results indicate right-hemispheric advantage in the capture of attention by negative emotion especially with object-based selection.     

Cross-Cultural Evaluation of the International Affective Picture System on an Indian Sample

The International Affective Picture System (IAPS) is widely used in emotion and attention research. Currently, there is neither a standard database of affective images for use in research with Indian population nor data on the way people from India respond to emotional pictures in terms of different dimensions. In the present study, we investigated whether self-reported Indian ratings are comparable to the original normative ratings (based on a North American sample) to evaluate its usability in Indian research context. The ratings were obtained from a sample of eighty Indian participants (age range?=?18 to 29 years, M _age?=?23.7, SD?=?2.67, 45 % females) on a stratified representative sample of 100 IAPS pictures. Similar to the normative data collected from the North American sample in the original IAPS database, the ratings were collected across three dimensions – valence (how pleasant/attractive or unpleasant/aversive), arousal (how calm or excited was the intensity of activation), and dominance (how controlling). Our results indicate similarities in valence ratings, but differences in arousal and dominance ratings between the Indian and the North American samples. The relationship between arousal and valence showed a similar (but less curved) boomerang shaped distribution seen with the North American sample. Unlike the North American sample, slopes were higher and intercepts were different for the Indian sample. However, the Indian sample also showed positivity offset and negative bias like the North American sample. These affective ratings show a fair amount of similarity but care is needed especially with arousal values in using these pictures for research with Indian population. While there are subtle differences in the relationship between different affective dimensions, there are also major similarities across cultures in affective judgments.     

Rapid communication: Global-local processing affects recognition of distractor emotional faces

Recent studies have shown links between happy faces and global, distributed attention as well as sad faces to local, focused attention. Emotions have been shown to affect global-local processing. Given that studies on emotion-cognition interactions have not explored the effect of perceptual processing at different spatial scales on processing stimuli with emotional content, the present study investigated the link between perceptual focus and emotional processing. The study investigated the effects of global-local processing on the recognition of distractor faces with emotional expressions. Participants performed a digit discrimination task with digits at either the global level or the local level presented against a distractor face (happy or sad) as background. The results showed that global processing associated with broad scope of attention facilitates recognition of happy faces, and local processing associated with narrow scope of attention facilitates recognition of sad faces. The novel results of the study provide conclusive evidence for emotion-cognition interactions by demonstrating the effect of perceptual processing on emotional faces. The results along with earlier complementary results on the effect of emotion on global-local processing support a reciprocal relationship between emotional processing and global-local processing. Distractor processing with emotional information also has implications for theories of selective attention.     

The exploration of meditation in the neuroscience of attention and consciousness

Many recent behavioral and neuroscientific studies have revealed the importance of investigating meditation states and traits to achieve an increased understanding of cognitive and affective neuroplasticity, attention and self-awareness, as well as for their increasingly recognized clinical relevance. The investigation of states and traits related to meditation has especially pronounced implications for the neuroscience of attention, consciousness, self-awareness, empathy and theory of mind. In this article we present the main features of meditation-based mental training and characterize the current scientific approach to meditation states and traits with special reference to attention and consciousness, in light of the articles contributed to this issue.     

A computational model of Parkinsonian handwriting that highlights the role of the indirect pathway in the basal ganglia

Parkinsonian handwriting is typically characterized by micrographia, jagged line contour, and unusual fluctuations in pen velocity. In this paper we present a computational model of handwriting generation that highlights the role of the basal ganglia, particularly the indirect pathway. Whereas reduced dopamine levels resulted in reduced letter size, transition of STN–GPe dynamics from desynchronized (normal) to synchronized (PD) condition resulted in increased fluctuations in velocity in the model. We also present handwriting data from PD patients (n = 34) who are at various stages of disease and had taken medication various lengths of time before the handwriting sessions. The patient data are compared with those of age-matched controls. PD handwriting statistically exhibited smaller size and larger velocity fluctuation compared to normal handwriting.