scholarly journals A Motion Direction Preference Map in Monkey V4

Neuron ◽  
2013 ◽  
Vol 78 (2) ◽  
pp. 376-388 ◽  
Author(s):  
Peichao Li ◽  
Shude Zhu ◽  
Ming Chen ◽  
Chao Han ◽  
Haoran Xu ◽  
...  
Science ◽  
2015 ◽  
Vol 349 (6243) ◽  
pp. 70-74 ◽  
Author(s):  
Adrian Wertz ◽  
Stuart Trenholm ◽  
Keisuke Yonehara ◽  
Daniel Hillier ◽  
Zoltan Raics ◽  
...  

Individual cortical neurons can selectively respond to specific environmental features, such as visual motion or faces. How this relates to the selectivity of the presynaptic network across cortical layers remains unclear. We used single-cell–initiated, monosynaptically restricted retrograde transsynaptic tracing with rabies viruses expressing GCaMP6s to image, in vivo, the visual motion–evoked activity of individual layer 2/3 pyramidal neurons and their presynaptic networks across layers in mouse primary visual cortex. Neurons within each layer exhibited similar motion direction preferences, forming layer-specific functional modules. In one-third of the networks, the layer modules were locked to the direction preference of the postsynaptic neuron, whereas for other networks the direction preference varied by layer. Thus, there exist feature-locked and feature-variant cortical networks.


Author(s):  
Filippo Ghin ◽  
Louise O’Hare ◽  
Andrea Pavan

AbstractThere is evidence that high-frequency transcranial random noise stimulation (hf-tRNS) is effective in improving behavioural performance in several visual tasks. However, so far there has been limited research into the spatial and temporal characteristics of hf-tRNS-induced facilitatory effects. In the present study, electroencephalogram (EEG) was used to investigate the spatial and temporal dynamics of cortical activity modulated by offline hf-tRNS on performance on a motion direction discrimination task. We used EEG to measure the amplitude of motion-related VEPs over the parieto-occipital cortex, as well as oscillatory power spectral density (PSD) at rest. A time–frequency decomposition analysis was also performed to investigate the shift in event-related spectral perturbation (ERSP) in response to the motion stimuli between the pre- and post-stimulation period. The results showed that the accuracy of the motion direction discrimination task was not modulated by offline hf-tRNS. Although the motion task was able to elicit motion-dependent VEP components (P1, N2, and P2), none of them showed any significant change between pre- and post-stimulation. We also found a time-dependent increase of the PSD in alpha and beta bands regardless of the stimulation protocol. Finally, time–frequency analysis showed a modulation of ERSP power in the hf-tRNS condition for gamma activity when compared to pre-stimulation periods and Sham stimulation. Overall, these results show that offline hf-tRNS may induce moderate aftereffects in brain oscillatory activity.


Author(s):  
Aida Mekhoukhe ◽  
Nacer Mohellebi ◽  
Tayeb Mohellebi ◽  
Leila Deflaoui-Abdelfettah ◽  
Sonia Medouni-Adrar ◽  
...  

OBJECTIVE: the present work proposed to extract Locust Bean Gum (LBG) from Algerian carob fruits, evaluate physicochemical and rheological properties (solubility). It aimed also to develop different formulations of strawberry jams with a mixture of LBG and pectin in order to obtain a product with a high sensory acceptance. METHODS: the physicochemical characteristics of LBG were assessed. The impact of temperature on solubility was also studied. The physical and the sensory profile and acceptance of five Jams were evaluated. RESULTS: composition results revealed that LBG presented a high level of carbohydrate but low concentrations of fat and ash. The LBG was partially cold-water-soluble (∼62% at 25°C) and needed heating to reach a higher solubility value (∼89% at 80 °C). Overall, the sensorial acceptances decreased in jams J3 which was formulated with 100% pectin and commercial one (J5). The external preference map explained that most consumers were located to the right side of the map providing evidence that most samples appreciated were J4 and J2 (rate of 80–100%). CONCLUSION: In this investigation, the LBG was used successfully in the strawberry jam’s formulation.


2019 ◽  
Vol 22 (1) ◽  
pp. 399-417 ◽  
Author(s):  
In Song Kim ◽  
Iain Osgood

We survey the literature on firms as primary actors in trade politics. In contrast with prevailing approaches, firm-centered models predict that trade internally divides industries and that larger firms are the strongest advocates for globalization. This new preference map alters extant predictions about the dynamics of interest group contestation over trade and suggests revised accounts for how political organization and institutions contribute to an open international order. We also explore the potential for new insights into the operation of the global trade regime, the politics of foreign investment, immigration and capital movements, and exchange rates. Poli-tical activities undertaken by firms are important areas for further research in international political economy: Their economic engagements directly affect the movement of goods, services, capital, and people across the globe.


PLoS Biology ◽  
2010 ◽  
Vol 8 (2) ◽  
pp. e1000305 ◽  
Author(s):  
Yu-Cheng Pei ◽  
Steven S. Hsiao ◽  
James C. Craig ◽  
Sliman J. Bensmaia

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