Since the function \( f(x) = 4x - 5 \) is a linear function with a positive slope, it is increasing over the interval \( 1 < x \leq 5 \). Therefore, the range of \( f(x) \) will be from just above \( f(1) \) to \( f(5) \).
The lower bound of the range is just above \( f(1) = -1 \), but since \( x = 1 \) is not included in the interval, the range starts from a value slightly greater than \(-1\).
The upper bound of the range is \( f(5) = 15 \).
Thus, the range of the function over the interval \( 1 < x \leq 5 \) is \((-1, 15]\).