temporal-quantification-mapk-induced-expression-single-yeast

Temporal Quantification of MAPK Induced Expression in Single Yeast Cells

The quantification of gene expression at the  single cell level uncovers novel regulatory mechanisms obscured in measurements  performed at the population ...

University of Lausanne

Behavioural, neuro-anatomical and clinical evidence suggests that different aspects of the visual scene are processed separately, but the extent to which the processing is carried out along segregated and independent parallel pathways is still debated. Moreover, it is also unclear whether these aspects are processed at the same rate, and their neural correlates reach consciousness at the same time. An experiment investigated this issue in the case of three attributes of 2D displays: colour, form, and movement. There were three conditions, one for each possible pairing of these attributes. Stimuli were combinations of two values for each attribute (red/green, circle/square, fixed/moving). In each condition the stimuli changed twice in close temporal succession, each attribute switching asynchronously between the two possible values. The observer's task was to report which change had occurred first. Response probabilities were computed for 13 values of the asynchrony, and transformed into estimates of perception time with the help of a psychophysical model. The results showed that colour and form are processed almost simultaneously. By contrast, movement perception is delayed by about 50 ms. The implications of these findings vis Ã  vis the so-called perceptual binding problem are discussed.

Colour, form, and movement are not perceived simultaneously.

Four experiments investigated the hypothesis that different attributes of a visual scene are processed by independent channels working asynchronously. Experiment 1 considered the attributes of colour, form, and movement of simple geometrical configurations. In each of three conditions, two of these attributes switched simultaneously between two fixed values (Green/Red, Circle/Square, Fixed/Moving). Participants indicated which of the two attributes changes was perceptually closer in time to a sound signal. Response probabilities varied as a function of the time of occurrence of the sound, showing that the processing of the movement channel is delayed with respect to the other two. A smaller but significant difference was also detected between the processing times for colour and form. Comparing Experiments 1 and 2 showed that movement velocity does not affect the delay with which movement onset is perceived with respect to colour. Experiment 3 contrasted colour and movement in the perception of a biological movement. The stimuli were video clips of a coloured ball being lifted by a hand. The colour of the ball changed a variable amount of time before or after the ball started moving. Participants indicated which of the two changes had occurred first. We found that, unlike in Experiments 1 and 2, movement perception no longer lagged colour perception. Experiment 4 tested the hypothesis that the disappearance of the asynchrony is due to perceptual anticipation. We discuss the implications of the results vis-Ã -vis current theories on perceptual binding and on the coding of dynamic events.

Perceptual asynchronies for biological and non-biological visual events.

We analyzed the management, resource use and conservation of the Ankarafantsika National Park (Madagascar) to develop a management plan, which provides a sustainable development strategy of the area while empowering the local residents. Using qualitative methodology we performed interviews with villagers and local organizations to assess the park's successes and failures from local stakeholders' perspectives. People living in a village with a permanent Madagascar National Parks (MNP) agent are more favorable to and supportive of the park conservation. People living in the park are supportive but are more divided. On the other hand, people living on the periphery of the park see conservation as more of a burden. Strategies like more equitable distribution of wealth, environment improvement and decentralization of power are discussed to achieve a more sustainable management plan based on community natural resources management. Short-term, medium, and long-term interventions from park authorities are needed to ensure the cooperation of local people in conservation endeavors.

Article	Year
Colour, form, and movement are not perceived simultaneously. Vision research\| PubMed ID: 11701183	2001
Perceptual asynchronies for biological and non-biological visual events. Vision research\| PubMed ID: 15126064	2004
Community management of natural resources: a case study from ankarafantsika national park, madagascar. Ambio\| PubMed ID: 23494265	2013

Delphine Aymoz

Biography

JoVE Journal Publications

Other Publications