Psychology
2014. Vol.5, No.1, 47-52
Published Online January 2014 in SciRes (http://www.scirp.org/journal/psych) http://dx.doi.org/10.4236/psych.2014.51009
Dysexecutive Syndrome in a Patient with Wilson’s Disease
Nataly Gutiérrez-Ávila1, Jimmy Zúñiga-Márquez1, Natalia Burgos-Torres1,
John Aria s -Valencia1, Patricia Quintero-Cusguen2, Rocio Acosta-Barreto 1
1Faculty of Psychology, San Buenaventura Bogotá University, Neuropsychology Master and
Specialization Program, Bogotá, Colombia
2Universitary Hospital La Samaritana, Bogotá, Colombia
Received August 30th, 2013; revised September 28th, 2013; accepted October 25th, 2013
Copyright © 2014 Nataly Gutiérrez-Ávila et al. This is an open access article distributed under the Creative
Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium,
provided the original work is properly cited. In accordance of the Creative Commons Attribution License all
Copyrights © 2014 are reserved f or SCIRP and the owner of the intellectual property Nataly Gutié rrez-Ávila et
al. All Copyright © 2014 are guarded by law and by SCIRP as a guardian.
Clinical Case Report: This paper presents the alterations and deficits in executive functions of a 33 years
old man with Wilson’s disease, patient at the Hospital Universitario La Samaritana in Bogotá, who in
2011 was diagnosed with cerebellar ataxia, and beginning to show a clinical picture of dysarthria and
generalized motor difficulties. The presence of neuropsychological disorders, as well as the results ob-
tained by Magnetic Resonance Imaging (MRI) of the brain and optical exam (Kayser-Fleischer rings)
confirmed the diagnosis of Wilson’s disease. Results and Conclusion: The neuropsychological profile of
the patient showed alterations of attention and mnemonic processes associated with frontal functioning, as
well as slowing-down of motor activities and low speed in processing information. The assessment of ex-
ecutive functions revealed impairment in cognitive flexibility, impulsivity and disinhibition, as well as
difficulties in the process of planning, organizing and monitoring. All of these features indicated the
presence of a dysexecutive syndrome in the patient and correlated with the results obtained by MRI.
Keywords: Wilson’s Disease; Executive Functions; Neuropsychological Profile; Dysexecutive Syndrome
Introduction
Wilson disease (WD), also known as hepatolenticular dege-
neration, is an autosomal recessive hereditary disorder that af-
fects copper metabolism causing an excessive accumulation of
this chemical in the body (Litwin et al., 2013; Hewlett, 2012;
Teleive et al., 2012; Pfeiffer, 2011; Taly, Prashanth, & Sinha,
2009), primarily in the liver, kidney and brain, producing alte-
rations and liver damage, neurological and psychiatric disorders.
It has been reported that the incidence of the disease is one in
every 30,000 live births (Moller et al., 2011) and affects both
men and women, although the neurological manifestations are
more common in male patients.
Regarding the symptoms produced by excess metal in the
Central Nervous System (CNS), the most affected areas that
show degeneration are the lenticular nucleus, putamen, caudate
head, globus pallidus, ventral thalamus, dentate nucleus, mid-
brain (except for the red nuclei), pons and in some cases there
is cerebellar atrophy. It is commonly observed that on magnetic
resonance imaging (MRI) these areas are hyperintense on T2,
and with the transcranial sonography tecnique, hyperechoic
lesions are found (Svetel, Mijajlovi, Tomiet et al., 2012; Huster
et al., 2012; Krysiak, Handzlik-Orlik, & Okopien, 2012; Nagel
& Miralles, 2007; Hitoshi, Iwat, & Yoshikawa, 1991).
WD presents a wide spectrum of manifestations depending
on the areas affected by the deposition of metal which are: the
liver form, the neurological and psychiatric forms and the form
with predominance of other organs (Roberts, 2011; Xu et al.,
2010; López & Serrano, 2007; Wilson, Alderman, Burgess,
Emslie, & Evans, 2003). Litwin, Gromadzka, Członkowska, et
al. (2012) conducted a retrospective study of 204 cases with
WD and found that the most common type is the neuropsy-
chiatric with 105 cases, followed by the liver type with 67, and
by the type with predominance of other organs, with 32 of the
204 cases studied.
The neurological form of the disease, is particularly charac-
terized by abnormal movements, postural and intentional tre-
mor, chorea, athetosis, myoclonus, seizures, ataxia, dysarthria,
hypophagia, hypersalivation, pyramidal signs and abnormalities
of eye movement (European Association for the Study of the
Liver-EASL, 2012; Svetel, Mijajlovi, Tomiet, et al., 2012). As
the disease progresses it is common to find a more complex
clinical picture (Lorincz, 2010).
With respect to the WD neuropsychological profile there is
little information at present. The majority of articles, research
and scientific texts make a description of the general aspects of
the neurocognitive profile (Carta et al., 2012; Birk et al., 2011;
Jacob & Srivatsa, 2011; Levy & Dubois, 2006).
In a study by Hegde, Sinha, Taly & Vasudev (2010), where
he presented the cognitive profile of twelve patients contrasting
it with MRI diagnostic studies and the signs and symptoms
reported, a greater impairment was found in motor speed (73%),
verbal working memory and focused and sustained attention
(50%), verbal learning (42%), processing speed (33% - 34%),
visual memory and verbal fluency (25% - 27%) and verbal
recognition (17%).
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N. GUTIÉRREZ-ÁVILA ET AL.
Schmitt et al. (2011), in a 40 years follow-up study with 36
patients diagnosed with WD reported that 25% of the patients
had neuropsychiatric manifestations where the common symp-
toms were attention deficit, changes in personality, irritability
and hypersomnia. Other studies attribute the changes in mood
and personality to a dopamine deficit present in the disease
(Litwin, Gromadzka, Członkowska, Poniatowska, & Poniato-
wska, 2013; Günther, Villmann & Hermann, 2011; Schmitt et
al., 2011; Popević, Kisić, Đukić, & Bulat, 2011; Hegde, Sinha,
Taly, & Vasudev, 2010).
With respect to executive functions (EF) and Wilson’s di-
sease, there is no conclusive research but there is an evidence
that regarding the relationship between frontal lobes and basal
ganglia, a relationship can be established with the presence of
alterations in the executive functioning (Pladdy, 2007).
The EF is dynamic processes which have a high degree of
dependence and is performed by different domains or neural
network interconnections that work as a unit involving a set of
cognitive skills related to processes of programming, regulation
and planning of the necessary behavior to achieve an adequate
level of adjustment and problem solving related to various cor-
tical-sub cortical areas of the Central Nervous System for its
correct functioning.
Alterations due to damage or injury of its structures and
networks result in the presence of low capacity for self-control
or self-direction, emotional lability, increased tendency to irri-
tability and excitability, impulsivity, erratic behavior, stiffness
and deterioration in self-care and grooming (Lezak, 1995; Ver-
dejo-García y Tirapu-Ustárroz, 2012).
Several studies have shown that executive functions are not
totally dependent on the prefrontal cortex, but there is a net-
work of neural interconnections that interact simultaneously
involving other areas of the CNS, especially connections with
subcortical structures such as basal ganglia (Suchy, 2009; Elliot,
2013).
Additionally, it has been established that there is an interac-
tion between the basal ganglia and other subcortical structures
such as the thalamus, subthalamic nucleus and globus pallidus
in the conformation and configuration of circuits that interact
with the frontal lobe for generating a regulated, controlled and
supervised behavior of executive functions (Verma, Patil, &
Lalla, 2012; Verdejo & Bechara, 2010; Suchy, 2009).
Thus, it has currently been established that the Executive
Functions depend on the integration of network circuits be-
tween the prefrontal cortex and the cortical subcortical struc-
tures and not just on one specified region. Lesions in these net-
works, even without impairment of the frontal lobe, can gener-
ate dysexecutive clinical pictures characteristic of prefrontal
syndromes as evidenced in progressive supranuclear palsy,
multiple system atrophy and Huntington’s disease. Therefore,
frontostriatal circuits are important in mediating executive
function (Elliot, 2013).
This case study aims to show the main changes in cognitive
processes presented in a patient with WD, highlighting the al-
terations or deficits in executive functions and their correlation
with neuroanatomical findings obtained by brain MRI. The case
study allows us to observe that the impairment in executive
functions presented in the WD is not due to injuries in frontal
regions as commonly occurs, but to lesions in the intercommu-
nication Prefrontal Cortex-Basal Ganglia—Prefrontal Cortex.
Method
Desing
A single case study was carried out, using a descriptive de-
sign and following an analytical e mpirical methodology. This
methodology was applied to a participant to assess his cognitive
functions, focusing the process on his executive functions
(Hernández, Fernández, & Baptista, 2006).
Participant
Male patient, aged 33, right laterality, with technical profes-
sional education level, currently unemployed. He has a history
of psychoactive substances consumption, specifically ethanol,
with an intake frequency of 3 to 4 times per week which per-
sisted for about 10 years. Consumption is terminated due to the
initiation of the major symptoms of the disease. Similarly, there
is history of non-abusive social use of cocaine for a year. In
2011 is diagnosed with cerebellar ataxia, initiating a clinical
picture of dysarthria and progressive motor impairment.
The patient is admitted to a hospital with a clinical picture of
ataxia, dysarthria, hypersalivation, hypophagia and constant
mood change. He goes through a multidisciplinary assessment
process which found, from the dermatology area, copper accu-
mulation after performing a hyperpigmentation biopsy in lower
limbs. In the different diagnostic tests performed by the internal
medicine staff, accumulation of this metal is found. The gas-
troenterology examination gives evidence of liver damage.
From the area of ophthalmology, the Kayser-Fleischer rings are
found (See Figure 1).
From the neurology area, a brain MRI was performed to the
patient. Findings show hyperintense lesions in the basal ganglia
(Figure 2) and midbrain (Figure 3), characteristic signs of the
disease. The frontal lobes were found intact.
Procedure
This research was conducted in three phases. In the initial
phase, an identification of the case was made at medical and
neurological level. Intake interview and signature of the in-
formed consent were carried out. In the second phase, the neu-
ropsychological assessment took place. And in the final phase,
the analysis of results and preparation of the final document
were done.
Instruments
Brief Neuropsychological Battery in Spanish, Neuropsi: This
is a screening test. In order to carry out its standardization, it
was applied to a sample of 800 neurologically intact subjects
aged between 16 and 85 years. The sample was divided into
four groups according to age and educational level. Reliability
was assessed by the test-retest method, with an interval of three
months between each application and marking was done by dif-
ferent assessors. Reliability between examiners was 0.89 to
0.95. This instrument allows assessing a wide range of cogni-
tive functions in patients with psychiatric, geriatric, neurologi-
cal and various medical problems (Ardila & Ostrosky, 2012).
Trail Making Test—TMT—Parts A and B: It is considered
that Part A measures motor, viso-spatial skills of visual search
and sustained attention, while Part B, additionally involves me-
ntal flexibility and divided attention. The test-retest reliability
varies greatly according to the specific study (0.60 to 0.90),
48

N. GUTIÉRREZ-ÁVILA ET AL.
Figure 1.
Kayser Fleischer Ring in the pa-
tient.
Figure 2.
MRI, hyperintense lesions in basal ganglia.
Figure 3.
MRI hyperintense lesion s on T2 at midb rain level in
patient with WD.
depending on the part or applied version and the pathology
(greater variability in schizophrenics, more stability in patients
with vascular disease). The temporal stability of the B-A dif-
ference is 0.71. The educational level has a significant influ-
ence on the scores, especially in Part B. No gender differences
were found. According to studies conducted, there is a signifi-
cant correlation between the test score (both parts) and the de-
gree of atrophy of the caudate nucleus (Ardila & Ostrosky,
2012).
Stroop D-Kefs: It is used to assess inhibition in executive
functions. The reliability of the test is carried out by the test-
retest method, being 0.84. Likewise, it is marked by different
assessors and obtains significant correlations (Lopez, Serrano,
Llano, Mateos , López, & Sánchez, 2010).
Wisconsin Card Sorting Test, WCST: neuropsychological
test used to assess cognitive flexibility. It is especially sensitive
to lesions involving the frontal lobes. The reliability was con-
ducted from a test-retest with a correlation of 0.93 for perse-
verant responses, 0.92 for perseverant errors, 0.88 for non-
perseverant errors, and concurrent validity of 70% (Scheres et
al., 2004).
Visual-verbal Memory Curve by Ardila: A list of twelve
words (animals, fruits, and body parts) is presented in three
trials. After each trial the subject is asked to tell all the words
he can remember. Also, intrusions and perseverations are re-
corded, as well as primacy and recency effects (Ardila & Os-
trosky, 2012).
Chip Test: the purpose of this test is to assess the under-
standing of verbal instructions of increasing complexity. The
application consists of presenting the chips to the patient and
asking him the respective questions which must be made
clearly and slowly. Words must not be emphasized. The ad-
ministration consists of 5 parts, only in Part A and B instruction
can be repeated once (Ardila & Ostrosky, 2012).
Wechsler Adult Intelligence Scale, WAIS III: The Wechsler
Intelligence Scale for adults consists of a Verbal Scale and a
Performance Scale, so that the application provides three scores:
a Verbal IQ, Performance IQ or Manual IQ, and a Full Scale IQ.
The subtests used were: block design which measures vis-
ual-motor coordination, perception, capacity for analysis, syn-
thesis, logic and reasoning. And the matrices subtest, that was
used specifically to determine the attention and planning capac-
ity.
Test of emotion recognition in faces by Baron Cohen (Faces
Test) and moral dilemmas of the theory of the mind.
Results
It was found that the patient showed slowness in the speed of
information processing, disinhibition, hypersexuality, perse-
vering behaviors, cognitive rigidity, difficulty to establish or
follow sequences, and failure in the development of strategies
for achieving goals. Additionally, he presents emotional lability,
low frustration tolerance and impairment in the abstraction
capacity, in encoding and recalling both verbal and visual stim-
uli mediated by his executive functioning. On the contrary, his
long term memory both episodic and semantic is preserved
(Table 1).
These findings account for a clinical picture of dysexecutive
syndrome in the patient, which was not the by-product of the
damage in the frontal structures, but in the cortico-subcortical
connections between basal ganglia and frontal lobes.
Discussion
The alterations found in the patient’s cognitive functions,
which correspond to a dysexecutive syndrome, may be associ-
ated with possible failure in the connections between basal
ganglia and frontal lobes. That is why dysexecutive syndrome
is a trigger for alterations involving different cognitive areas
(Ardila, 2008).
Results of this study are similar to those reported by Clark,
Collazo, Ruenes & García (2011) who showed that patients
with a neurological form of WD had no major impairment in
basal ganglia, but they did in their interconnections, showing
poor operating performance on executive functioning, memory,
visuospatial processing and verbal and abstract reasoning.
Many years ago, the research by Posner & Raichle (1994),
identified the existence of interconnected neural networks to
describe attention processes. They suggested that the central
control mechanism of the alert system, the orientation system
and the executive system forms a dependent circuit, where each
one of them is responsible for a specific task in the attention
process, but interacting dynamically and integrating into the
executive system the interconnected networks of the frontal
lobe, the anterior cingulate and the basal ganglia, which makes
cognitive functions also interdependent in this process.
In summary, the present case describes a patient who shows
neurological involvement both in memory and attention medi-
ated by the executive dysfunction which decreases the possibil-
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N. GUTIÉRREZ-ÁVILA ET AL.
Table 1.
Results of neuropsychological test.
Neuropsy
Score Score Normal
89 112 - 102
Trail Making Test A
Time Score Normal
164 seconds 27 - 32 seconds
Trail Making Test B
Time Score Normal
677 seconds 56 - 69 seconds
WAIS III
Direct Score Normal Score
Cubes 4 - 8 3
Matrices 11 - 12 8
Wisconsin Card Sorting Test
Score Normal Score
Trials 128 72
Categories 1 5
Corrects 62 67
Perseverative Errors 41 (32%) (5%)
Conceptual level 40 67
Ardila`s Verbal Memory C urve
Score Normal Score
Initial Volume 5 7 ± 2
Maximum Volume 9 10
Trials 10 4
Evocation 3 ( 20) minutes 9 (5) 10 (8)
Ardila`s V i sual Mem ory Curve
Score Normal Score
Initial Volume 5 7 ± 2
Maximum Volume 10 10
Trials 3 4
Evocation 3 ( 20) minutes 9 (8) 10 (8)
Test of emotion recognition in faces
Corrects Errors
17/20 Guilt—Anger/Boredom—Fear
ity of making new effective learning, develops appropriate en-
coding and recalling strategies, inhibits irrelevant information
effectively, holds his attention on the tasks and foster flexibility.
All of these impairments can be attributed more to a dysfunc-
tion in the cortical-subcortical neuronal interconnection which
interferes with the proper functioning of cognitive processes.
The research that gives account of affectations on cognitive
functions in WD suggests a deficit in different areas of these
operations. However, considering the role of basal ganglia—
executive functions, it is proposed that the main neuropsy-
chological deficit caused in WD lies in executive functions. In
similar profiles to the one reported in this study the other cog-
nitive impairments evidenced are secondary to such a deficit.
Although the description of executive functions and neuro-
psychological involvement made in this study is similar to the
descriptions made by other researchers, it diffe rs that it empha-
sizes the relationship between cortical and subcortical struc-
tures in the conformation of the dysexecutive clinical picture
present in WD and points out that the impairments in other
domains are secondary to this one.
On the other hand, it is important to note that although the
patient has a history of chronic alcohol consumption, and that
this condition has some effects on the Central Nervous System
—CNS—which, in turn, affects cognitive functions, several
studies have found a phenomenon that has been called “deficit
recovery following abandonment” (Garrido & Fernandez,
2004), which refers to a decline in cognitive functions immedi-
ately to cessation of the substance. But after overcoming the
withdrawal symptoms and having abandoned consumption
completely, patients are able to recover their functions within
approximately one month. However, at present, the patient in
this case study has been in abstinence for more than two years
which leads to relating his clinical dysexecutive syndrome di-
rectly with WD and copper accumulation in the basal ganglia
(Bidaki et al., 2012; Carta, Mura, Sorbello, Farina, & Demelia,
2012; Di Stefano, Lionetti, Rotolo, La Rosa, & Leonardi, 2012;
Castañeda, Ubilluz, Ávalos, Escalante, & Nicoll, 2002).
Finally, it is important to note that the projections and cir-
cuits between and from the basal ganglia to the cortex have
been extensively described in the literature. It is now known
that in addition to their circuits and projections with the frontal
lobes there are also connections with other cortical areas. Tar-
get projections of the thalamic nuclei, superior colliculus, re-
ticular formation and pedunculopontine nucleus are located
toward the temporal and parietal areas. Furthermore, it has been
reported that such nuclei have a strong participation in the
modulation of behavior (Peng, Lutsenko, Sun, & Muzik, 2012;
Cheon et al., 2010; Stocco, Lebiere & Anderson, 2010; Bernal
& Calle, 2007). This explains the wide variety of cognitive
symptoms present in the clinical case shown in this article and
the dynamism and complexity of executive processes in the
CNS.
Acknowledgemen ts
First, we wish to express our gratitude and appreciation to
the patient and his family for allowing documentation of the
case, and thus being able to contribute to the scientific com-
munity. Second, to the University Hospital La Samaritana, the
MD Yamile Sierra, and to the neurologists Jose Hernandez and
Pilar Guerrero.
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