hello everyone
In the construction of functional gradients, the positive/negative sign has no inherent practical meaning. Therefore, functional gradients can essentially be flipped (positive to negative and vice versa). However, the t-values calculated for group differences based on these functional gradients do have practical meaning, and they are directly linked to the sign chosen during gradient construction. For example, if we estimate a positive T-value for a group difference, flipping the sign of the functional gradient will cause the T-value to become negative. How should this situation be interpreted? Do the T-values derived from the gradient still hold actual biological significance?