Like most people, you are ignorant to the basic, technical definition of political conservatism. Firstly, you need to use your sociological imagination and conceive of human societies as complex, integrated, stable systems, not unlike biological organisms. In its broadest sense, conservatism refers to systemic elements that function to maintain (conserve) the status quo. However, since the formation of the first class societies some 10,000-12,000 years ago fostered widespread economic and general social inequality, a problem we are still fighting today, conservatism has been characteristically inegalitarian; its function has thenceforth been to preserve this thoroughly unequal state of affairs.
One of the main conservative elements in mainstream psychology is its biodeterminist tendencies. Biodeterminism is conservative in both the broad and more narrow senses described above. It functions to mislead people into thinking that social inequalities are "natural," immutable givens resistant to change through progressive political action, and to divert attention away from the true (sociocultural, political-economic) origins of these social problems. Basically, this ideology is a form of systemic self-preservation that bolsters inequality.
You seem to think that psychology is largely progressive as opposed to conservative. If this is your view, might you elaborate?