Model Parameters
| Model Parameter . | Parameter Description . | Values Tested . |
|---|---|---|
| stimWidth | Spatial extent of stimulus | 25 (fixed value) |
| stimFeatureWidth | Extent of stimulus along feature dimension | 25 (fixed value) |
| ExWidth | Spread of stimulation field along spatial dimension | 30, 40, 50, 60, 70, 80, 90 or 100 |
| EthetaWidth | Spread of stimulation field along feature dimension | 30, 40, 50, 60, 70 or 80 |
| IxWidth | Spread of suppressive field along spatial dimension | = C*ExWidth, where C = 1.5, 2, or 2.5 |
| IthetaWidth | Spread of suppressive field along feature dimension | = C*EthetaWidth, where C = 1.5, 2, or 2.5 |
| AxWidth | Extent/width of the spatial attention field | = ExWidth |
| AthetaWidth | Extent/width of the featural attention field | = EthetaWidth |
| ApeakX | Peak amplitude of spatial attention field | 2, 4, 6, or 8 |
| ApeakTheta | Peak amplitude of the feature-based attention field | 2, 4, 6, or 8 |
| Abase | Baseline of attention field for unattended locations/features | 1 (fixed value) |
| baselineMod | Amount of baseline added to stimulus drive | 0, .1, .3, .5, or 1 |
| baselineUnmod | Amount of baseline added after normalization | 0, .1, .3, .5, or 1 |
| sigma | Constant that determines the semisaturation contrast | 1e−6 (fixed value) |
| Ashape | either “oval” or “cross” | “oval” (fixed value) |
| Model Parameter . | Parameter Description . | Values Tested . |
|---|---|---|
| stimWidth | Spatial extent of stimulus | 25 (fixed value) |
| stimFeatureWidth | Extent of stimulus along feature dimension | 25 (fixed value) |
| ExWidth | Spread of stimulation field along spatial dimension | 30, 40, 50, 60, 70, 80, 90 or 100 |
| EthetaWidth | Spread of stimulation field along feature dimension | 30, 40, 50, 60, 70 or 80 |
| IxWidth | Spread of suppressive field along spatial dimension | = C*ExWidth, where C = 1.5, 2, or 2.5 |
| IthetaWidth | Spread of suppressive field along feature dimension | = C*EthetaWidth, where C = 1.5, 2, or 2.5 |
| AxWidth | Extent/width of the spatial attention field | = ExWidth |
| AthetaWidth | Extent/width of the featural attention field | = EthetaWidth |
| ApeakX | Peak amplitude of spatial attention field | 2, 4, 6, or 8 |
| ApeakTheta | Peak amplitude of the feature-based attention field | 2, 4, 6, or 8 |
| Abase | Baseline of attention field for unattended locations/features | 1 (fixed value) |
| baselineMod | Amount of baseline added to stimulus drive | 0, .1, .3, .5, or 1 |
| baselineUnmod | Amount of baseline added after normalization | 0, .1, .3, .5, or 1 |
| sigma | Constant that determines the semisaturation contrast | 1e−6 (fixed value) |
| Ashape | either “oval” or “cross” | “oval” (fixed value) |
Model parameters from the normalization model of attention (Reynolds & Heeger, 2009) that we used in model simulations. We defined the stimulus and response matrices as varying from −200 to 200 along both spatial and feature dimensions (arbitrary units). We generated the model predictions for every combination of the above model parameters, resulting in 172,800 sets of model predictions.