Languageproduction and comprehension disorders are frequent in dementia. Language comprehensionat the single word level (i.e. in picture-word matching task) can be in mildly cognitively impaired patientspreserved, so clinically the language processes seem to be normal, but more comprehensivelanguage testing (i.e. at sentence level) can reveal substantial impairments even inpatients with mild dementia.

To detect the language deficits inpatients with MCI and dementia and to determine the relationship between thesedeficits and the severity of cognitive disturbances.

In the sample of 72 cognitively declined patientsof Department of psychiatry of University Hospital in Bratislava, Slovakia weevaluated severity of cognitive impairment by MMSE and MoCA instruments. Weused our own sentence comprehension test, designed for Slovak speakingindividuals.

Normal performance in sentence comprehensiontest we registered in 5 from 7 patients with MCI, but only in 2 patients from29 with mild, 2 patients from 32 with moderate and no patient from 4 withsevere dementia.

Testing of language functions inpatients with dementia only at the single word level (what is typical inroutine clinical practice) doesn´t capture real communication disturbances. Atleast in patients with MCI and mild dementia is very useful to carry out moredetailed language testing (including items at sentence level), which can revealthe onset of language disturbances. Languagespecific test should be used to discover comprehension deficits at early stageof dementia.