Personality development and the dually diagnosed person.

Zigler et al. (1989) wrote a position paper, not an experiment.

They argued that life history shapes personality in people with intellectual disability.

The authors urged clinicians to fold developmental thinking into mental-health plans.

The paper claims that years of help from others can breed passivity.

Low expectations from staff become low expectations from self.

These patterns act like risk factors for anxiety and depression.

Dosen (2005) extends the idea by showing how to add developmental level to any psychiatric diagnosis.

Einfeld et al. (1995) widens the lens, saying whole taxonomies need fixing, not just single labels.

Luckasson et al. (2013) and Matson et al. (2013) update the language, pushing terms like ‘intellectual disability’ over older words.

The thread is clear: start with personality, end with better names and tools.

When you see clingy or helpless behavior, ask what the client has learned across decades, not just what happened last week. Build goals that grow autonomy and raise self-expectation. Swap deficit labels for growth language in reports and team meetings.