Experimental setup for scaling of the neuronal tuning curve.
- Author
- Frederik Beuth
Data: McAdams and Maunsell, 1999, Fig. 4
Significant results (p. 433, right column):
- In the population (Fig. 4), attention significantly strengthened responses to the attended stimuli.
- In individual cells, it was significant in 20% of the cells. For the rest, see Fig. 2A.
- The population shows no significant changes in tuning width (Fig. 2B) or preferred direction (Fig. 2D), but it shows a sign. change in the asymptote (Fig. 2C). However, some individual cells deviate from this.
Setup:
- Stimuli have either sizes between 1°-5° (2xSD of 0.6°-2.2°) or between 0.6°-2.2°. Which version is unclear as the text is not precisely formulated. They were presented at 1-5° eccentricity. V4 RF size are between 3°-4.8° at this eccentricity (Smith et al., 2001). => We model the stimulus as large as the RF.
Calibration of the fit:
- Attention factor is equal for all orientations, indicating response gain effect.
- The suppression at the peak result from weak surround suppression.
- The flank slope indicates an pE value of around 1.5, which demands to decrease vE to 2.
- Feature-based suppression occurs from peak of the curve to the borders. The data shows no suppression, thus cancels out the suppression with a broad tuning of the input and a baseline