Self-managed investment trust Alliance Trust has confirmed the appointment of Anthony Brooke and Rory Macnamara as non-executive directors.On Wednesday, the FTSE 250 group said both Brooke and Macnamara, who is currently a director of the Dunedin Income Growth Investment Trust, Augean, Essenden and Mears Group will step into their new roles on 24 June.The company had originally unveiled the new member of the board on 28 April following its Annual General Meeting.Alliance Trust shares were down 0.10% to 497.38p at 15:13 on Wednesday.