Depression is one of the leading causes of disability worldwide, and cognitive symptoms, such as difficulty completing everyday tasks, contribute to the disability associated with depression. Almost all people with depression experience problems with attention, concentration, and memory.
This cognitive impairment tends to persist even in the recovery phase of depression when mood symptoms start to improve. People with persistent cognitive symptoms often then experience poorer outcomes such as impaired work functioning and are at increased risk for relapse.
To test whether modafinil could help with these cognitive functions, researchers from the Department of Psychiatry and the Behavioural and Clinical Neuroscience Institute at the University of Cambridge, asked sixty participants who have been previously diagnosed with depression to complete computerized memory, attention and planning tasks after receiving modafinil or placebo. The results showed that the participants who received modafinil experienced significant memory improvements.
The researchers found that participants who received modafinil made fewer errors in two specific types of memory, episodic memory, and working memory, both of which are important in day-to-day activities. Episodic memory is used when remembering events such as where we left our keys in the house or remembering where we parked our car, whereas we use working memory when we are rehearsing a new telephone number or when rehearsing a new passcode to access a computer network, for example.