The present invention provides a method of screening for compounds which affect the cleavage of EphA7 by γ-secretase. The method includes the following steps: (i) contacting a first biological composition containing γ-secretase or a biologically active fragment thereof with a second biological composition containing EphA7 in the presence and absence of a candidate compound; (ii) measuring the cleavage of the EphA7 in the presence and absence of the candidate compound; (iii) selecting those candidate compounds which affect the cleavage of the EphA7 by γ-secretase; and (iv) identifying the candidate compounds selected in step (iii) as compounds which affect the cleavage of EphA7 by γ-secretase.