Motor inhibition associated with the affordance of briefly displayed objects

Research has demonstrated that left- and right-hand responses are facilitated when they are performed with the hand compatible with the orientation of a viewed object. This suggests that graspable objects automatically activate the motor representations that correspond to their orientation. It has recently been proposed that similar positive stimulus-response compatibility effects (PCE) may turn into negative compatibility effects (NCE) when a prime object is displayed very briefly. These NCEs are suggested to reflect motor inhibition mechanisms--motor activation triggered by briefly viewed objects may be treated by the motor system as unwanted, and thus it is rapidly inhibited. We examined whether the motor activation triggered by the orientation of a task-irrelevant object is similarly inhibited when the object is displayed briefly. In Experiment 1, a NCE was observed between the orientation of an object and the responding hand when the object was displayed for 30 or 70 ms. The effect turned into a PCE when the object was displayed for 370 ms. Experiment 2 confirmed that this motor inhibition effect was produced by the handle affordance of the object rather than some abstract visual properties of the object.     

BDNF is a novel marker of cognitive function in ageing women: the DR's EXTRA Study

Brain-derived neurotrophic factor (BDNF) is one of the key molecules modulating brain plasticity. While low circulating levels of BDNF have been suggested to predispose to Alzheimer's disease, very little data are available on its association with cognitive function in general population. We evaluated the association between plasma BDNF levels and cognition in a representative population sample of ageing men and women. The subjects (n=1389) were participants of the Dose-Responses to Exercise Training (DR's EXTRA) Study and represent a random sample of Eastern Finnish people (684 men and 705 women), 57-79 years of age at baseline of the study. Plasma BDNF levels were measured by enzyme-linked immunosorbent assay (ELISA). Cognitive function was evaluated using the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropsychological test battery. Women had a higher mean (+/-SEM) plasma BDNF level than men (1721+/-55vs. 1495+/-54pg/ml, P<0.001). In women, 1 SD decrease in BDNF increased the risk for a low score in Naming Test by 53% (95% CI 1.21-1.92, P<0.001), in Mini-Mental State Examination by 63% (95% CI 1.21-2.20, P=0.001), in Word List Memory by 56% (95% CI 1.08-2.26, P=0.019), in Word List Recall by 50% (95% CI 1.10-2.05, P=0.010), in Word List Saving by 49% (95% CI 1.12-1.99, P=0.007), and in Word List Recognition by 64% (95% CI 1.19-2.25, P=0.002). Data were adjusted for age, education, depression, impaired glucose metabolism, cardiovascular disease, antihypertensive medication, lipid lowering medication, use of sex hormones, smoking, alcohol consumption, storing time of plasma in the freezer and platelet count. BDNF was not associated with cognition in men. Present data suggest that plasma BDNF is a biomarker of impaired memory and general cognitive function in ageing women.     

Women's human rights violations: Cameroonian students' perceptions

Cameroonian university students (N = 666) assessed whether certain different societal positions that the law grants to women and men (the husband chooses the marital home, the husband wields parental power, a married woman cannot freely engage in trade, the husband administers his wife's personal property) and certain cultural practices (female genital mutilation, parents arranging their children's marriage) were seen as violations of women's human rights. Justifications for the choices were also analysed. Female genital mutilation was most often seen as a violation of women's human rights, and the husband selecting the marital home was least often seen as a violation. These differences were explained by cultural specificities. Women more often than men saw the cases as violations of rights. Respondents coming from the North saw the cases less often as violations of rights than respondents from other geocultural areas, which was in accordance with their previously observed higher collectivism. Copyright © 2009 John Wiley & Sons, Ltd.     

The Effect of Language Immersion Education on the Preattentive Perception of Native and Non-native Vowel Contrasts

Proficiency in a second language (L2) may depend upon the age of exposure and the continued use of the mother tongue (L1) during L2 acquisition. The effect of early L2 exposure on the preattentive perception of native and non-native vowel contrasts was studied by measuring the mismatch negativity (MMN) response from 14-year-old children. The test group consisted of six Finnish children who had participated in English immersion education. The control group consisted of eight monolingual Finns. The subjects were presented with Finnish and English synthetic vowel contrasts. The aim was to see whether early exposure had resulted in the development of a new language-specific memory trace for the contrast phonemically irrelevant in L1. The results indicated that only the contrast with the largest acoustic distance elicited an MMN response in the Bilingual group, while the Monolingual group showed a response also to the native contrast. This may suggest that native-like memory traces for prototypical vowels were not formed in early language immersion.     

Vowel perception: A neuroradiological localization of the perception of vowels in the human cortex

Whether the perception of vowels takes place in the right or left cerebral hemisphere, or is dependent on bilateral cortical processes, is of importance in our treatment of patients with language deficiencies. To investigate this problem a phonetic test with a series of vowellike stimuli was administered to 68 right-handed adult patients with cerebral lesions, mainly of vascular origin. The results were compared to the results in a control group of 19 speech therapists. Second, a neuroradiologic method was developed in order to visualize the anatomic site of Wernicke's area in the left hemisphere on CT scans. This method formed the basis for an evaluation of the extent and localization of the patients' lesions in Wernicke's area. Of 46 patients with lesions in the left hemisphere, 19 had no perceptual disturbances and 27 had severe perceptual disturbances with lesions predominantly located in Wernicke's area. Twenty-two patients with lesions in the corresponding area in the right hemisphere showed no perceptual disturbances. The results of this investigation appear to indicate that the perception of vowels in right-handed persons is unilaterally located in Wernicke's area in the left hemisphere.     

Correlation of eye color on self-paced and reactive motor performance.

Researchers continue to examine the distinctiveness of motor performance by dark- versus light-eyed individuals. Dark-eyed individuals generally perform better at reactive type tasks (boxing, hitting a ball, defensive positions in football, rotary pursuit), while light-eyed individuals perform better at self-paced tasks (bowling, golf, pitching baseballs). Subjects performed two tasks, rotary pursuit and ball tossing (with light and dark background). Eye color (light or dark) and accuracy of performance were recorded for each subject. No significant difference was found between eye color and performance on the pursuit rotor (reactive activity). A significant difference was found between men's and women's performance in throwing a ball (self-paced activity) at a light-colored background.     

PHYSICAL AND PSYCHIATRIC CORRELATES OF GENDER DISCRIMINATION

We tested the model that sexist discrimination, measured by the Schedule of Sexist Events (SSE), would account for additional variance in women's physical and psychiatric symptoms, above and beyond that accounted for by generic stressors. A series of hierarchical regression analyses, predicting symptoms on 10 different symptom outcome measures from generic stress and sexist stress (discrimination) were conducted, with the generic stressors entered on the first step and sexist discrimination on the second. Results revealed that sexist discrimination contributed significantly to the variance in women's symptoms, accounting for additional variance in those symptoms. Furthermore, sexist discrimination accounted for more of the variance than did generic stressors in premenstrual, depressive, obsessive-compulsive, somatic, and total psychiatric and physical symptoms. These findings varied with the age and ethnicity of the women and with the symptom measure used, but nonetheless suggest that sexist discrimination plays a significant role in women's most prevalent symptoms.     

Effects of variations in the temporal distribution of reinforcements on interval schedule performance

Pigeons were exposed to variable-interval and fixed-interval schedules and schedules approximating variable-interval and fixed-interval schedules. The probabilities of the variable-interval and fixed-interval components in a mixed fixed-interval variable-interval schedule in Experiment I and the minimum and maximum interreinforcement intervals in Experiment II in a variable-interval schedule were manipulated to create intermediate schedule contingencies and contingencies approximating simple variable-interval or fixed-interval contingencies. Maximal control by time as defined by quantitative indices of the temporal pattern of response occurred as fixed-interval contingencies were approximated and minimal control occurred as variable-interval contingencies were approximated. Changes in the temporal pattern of response were systematically related to changes in the temporal distribution of reinforcements with both procedural definitions for manipulating the temporal distribution of reinforcements.