Endogenous and exogenous attention in patients with conversion paresis

Area of Science:

• Neuroscience
• Cognitive Psychology

Background:

• Conversion paresis involves motor deficits without organic cause.
• Previous research suggests impaired higher-level control functions in conversion disorders.
• Attention mechanisms, including voluntary and involuntary orienting, are crucial for cognitive processing.

Purpose of the Study:

• To investigate endogenous and exogenous attention in patients with conversion paresis.
• To examine if attention deficits in conversion paresis are linked to inhibitory control.
• To compare attention performance in verbal versus limb response conditions.

Main Methods:

• Utilized Posner's 'covert orienting of visual attention' task.
• Included eight patients with conversion paresis and eight healthy controls.
• Administered the task in both verbal and limb response conditions.

Main Results:

• Patients exhibited weakened endogenous cue effects at a 150-ms stimulus onset asynchronicity (SOA).
• No inhibition of return (IOR) was observed in the exogenous condition for patients.
• Similar attention deficits were found in verbal responses and responses with affected limbs.

Conclusions:

• Findings suggest an impairment in voluntary attention in conversion paresis.
• High-level inhibition may interfere with stimulus orientation, particularly for responses involving affected limbs.
• Attention deficits in conversion paresis manifest at a high, abstract cognitive level.