Psychology is applied in accounting and finance in many ways.

Psychologists studies human behavior and have developed theories regarding how people behave. Most financial accounting issues deal with matters of human behavior, such as the judgments and decisions of managers, investors, analysts, and auditors. Consequently, psychology offers theories from which financial accounting researchers can draw to motivate hypotheses and interpret results.

Some of the psychology theories that are applicable to financial accounting issues include voluntary disclosure, earnings management, analyst forecasts, attribution theory, prospect theory, motivated reasoning and expertise

I would suggest your research could focus on the extreme ends of the normal curve of human behaviour.

At one end of the normal curve there are high functioning achievers who make a significant positive difference to their organizations. At the other end of the normal curve are sociopaths who find ways to break internal financial controls and defraud their organizations for their own personal enrichment.

A couple of published papers summarizing how these games are played in the finance world which might help your literature review are attached here:

Article Detecting supplier payment errors and fraud using a data war...

Article Retailer vulnerability to lottery fraud

Article Retail point of sale fraud prevention and detection using in...

The disciplines in accounting and finance that examine how psychology affects accounting and finance phenomena are:

1. Behavioural Accounting

2. Behavioural Finance

Some academic journals publish good research on the intersection of psychology with accounting and finance