The present experiment investigated whether
the gambling of American Indian (AI) and non-AI
participants would be sensitive to the actions and/or
ethnicity of another gambler (i.e., a confederate) when
playing a slot-machine simulation. Eight male AIs
and eight male non-AIs participated in fi ve gambling
sessions. In one, the participant gambled alone. In
the other four, the participant played in the presence
of a confederate of the same or diff erent ethnicity who
gambled the entire session or quit after playing fi ve
times. The gambling of the AI and non-AI participants
did not diff er, nor was either group sensitive to
whether the confederate was AI or non-AI. Gambling
behavior was altered by the confederate's actions, with
participants gambling less when the confederate left the
session than when alone or when the confederate stayed
and gambled. These results suggest that the diff erences
in gambling problems between AIs and non-AIs
reported in the overall literature may not be a function
of ethnicity per se. They also suggest that the actions of
other gamblers may inhibit gambling, which may have
treatment implications.