Resistance to extinction as a function of IQ and reinforcement ratio among retarded children

Area of Science:

• Psychology
• Neuroscience
• Developmental Psychology

Background:

• Intellectual disability is characterized by limitations in intellectual functioning and adaptive behavior.
• Understanding cognitive processes like inhibitory control is crucial for assessing intellectual functioning.
• Behavioral persistence during extinction is a key indicator of learning and cognitive control.

Purpose of the Study:

• To investigate the relationship between intelligence levels (IQ) and resistance to extinction in children with mental retardation.
• To determine if the 'period reinforcement extinction effect' varies across different IQ levels.

Main Methods:

• Children with mental retardation (IQ 50-60, 30-40, 20-below) were trained to bar-press for reinforcement on variable ratio schedules (VR2, VR4).
• Behavioral responses were recorded during extinction phases (when reinforcement was withheld).
• The number of responses during extinction was analyzed in relation to IQ level.

Main Results:

• An inverse relationship was observed between IQ and resistance to extinction; lower IQ correlated with greater persistence.
• The period reinforcement extinction effect was present across all groups.
• No significant interaction was found between IQ level and the period reinforcement extinction effect.

Conclusions:

• Inhibitory control, a key cognitive function, appears to be a significant parameter that differentiates intelligence levels.
• Resistance to extinction may serve as a behavioral marker for assessing inhibitory control in individuals with intellectual disabilities.
• These findings contribute to understanding the behavioral manifestations of varying intellectual capacities.