Rehabilitacija - Letnik VII. 11111! . -1-(2008/ 
EXECUTIVE ABIL ITY ANO DAILY LIVING 
PERFORMANCE IN PATIENTS WITH 
ALS 
V štukovnik
1
. G. Repovš
2
, J. Zidar
1 
1 
Institute of Clinical Neurophysiology, University Medica! Centre Ljubljana, Ljubljana, Slovenia 
2 
Department of Psychology, Washington University in Saint Louis, USA 
Amyotrophic lateral sclerosis (ALS) was traditionally 
thought to affect solely the lower and upper motor neurons. 
Recent studies suggest that the pathogenic processes of 
ALS are more extensive, involving a wider dysfunction of 
cortical grey and white matter with clinical correlates in the 
impairment of cognitive abilities. Cognitive deterioration 
has until recently been associated almost exclusively with 
a subgroup of 3-5% of ALS patients with frontotemporal 
dementia. However, a number of latest neuropsychologi­
cal investigations demonstrated selective impairments of 
the executive and memory functions in nondemented ALS 
patients (25-75% ). The relevance of these results for every­
day life, however, stili remains in question, thus demonstrat­
ing the need for the development and use of an ecologically 
valid test ( 1 ). 
The purpose of this preliminary study was to assess the 
prevalence of cognitive dysfunction in ALS and also dys­
function 's impact on patients' daily activities. Wc evaluated 
16 patients with ALS, according to EI-Escorial Criteria of 
"possible", "probablc" or "definite" ALS, and with a mean 
age of M = 59.6 (SO = 7.3) on a battery of standardized 
neuropsychological tests as well as a specially designed and 
ecologically valid test of executive functions called Medi­
cation Scheduling task - MST (2). With MST, paticnts are 
asked to coordinate multiple rules in order to create a safe 
daily schedule of medications. 
Both, standardized neuropsychological measures as well 
as the ecologically valid measure of executive functions, 
revealed important deficits in cognitive performancc of 
ALS patients. Using the cut-off value of the 15'" percen­
tile to mark the deficient activity (3), wc found tliat most 
II 
patients demonstrated the same kind of impaired activity. 
i.e. placing incorrectly the pills to the medica! schedule
and neglecting to follow the rules while executing the MS1
task. The MST task's high demand for cognitive controL
including the ability to coordinate multiple tasks and/01
multiple sources of information, the application of strate­
gies to a novel problem and the ability to monitor incom­
ing information for relevance to the task at hand, seems to
presen! great difficulties to patients with ALS and could
possibly interfere with the planning and executing of their
daily activities. Further explorations of patients' daily liv­
ing performance are necded. Knowing whether or not an
ALS patient has cognitive impairment brings up important
considerations regarding the management of the patients,
including a higher degree of involvement and supervision
on the part of their caretakers.
References: 
l. Chaytor N, Schmitter-Edgecombe M, Burr R. Improving
the ecological validity of cxecutive functioning asscss­
mcnt. Arch Ciin Neuropsychol. 2006; 21 (3): 217-27.
2. Schefman J, Foster ER, Lim A, Perantie O. Repovš G,
Baum C, Hearshey T. The medication Scheduling Ta sk:
The development of a naturalistic executive function­
ing task. Presented at the 2006 American Occupational
Therapy Association Meeting: Charlottc, NC.
3. Ocutsch Lezak M, Howieson OB, Loring OW. Ncuropsy­
chological assessment. 4'" ed. Oxford University press:
Oxford, New York etc.; 2004.