Emotions can play a direct role in gambling loss particularly in sports betting but in casinos games like slots, I do not think so. Because in slots, as soon as you spin the wheels, the outcome(a win or a loss) is already determined. The indirect implications of emotions in further losing is in chasing the loss due to being allowing your emotions to cloud your judgement.
Despite your strategies, in gambling it is what it is, loss is bound to happen that is why the gambler must be disciplined enough to gamble with money he or she can afford to lose. He or she must let their emotions get the best of them by making them to borrow money to gamble. Responsible gambling practices must be upheld at all times.