Decreased car handling performance, increased reaction times, impaired time and distance estimation, inability to maintain headway, lateral travel, subjective sleepiness, motor incoordination, and impaired sustained vigilance have all been reported. Name Email Website Notify me of follow up comments via e-mail. Actually prefer to play the harp that matches the key of the song playing. Producing single notes or chords, hohner manufacturing the Melodica is both solo and orchestral instrument, blending beautifully with other instruments. Yes it is true that in some cases excessive use can cause mental side affects.