I don't think the psychological effects would have made too much difference to the players, I think the biggest psychological influence will be over the referees, they're intimidated into giving decisions the way of the home team.
The biggest issue we had after the coach attack would have been due to the comedown from the adrenalin rush in the lead up to the match, the coach attack and the sight of loads of feral scousers wouldn't have been scary to the people in the coach but it will have triggered an involuntary fight or flight response. Some of the after effects of this adrenaline rush are tiredness, lack of coordination, tremors and difficulty in concentrating amd they usually hit around an hour after the adrenaline response started (approximately just in time for the game to kick off). This is why sports people try to relax and focus before the event and get fired up just before they begin competing and also why these shit house tactics helped Liverpool so much in that game (aided and abetted by a 'generous' German referee).