Page 70 - JCBP-2-4

Journal of Clinical and
Basic Psychosomatics Profiles of attention and executive function in epilepsy versus psychogenic seizures

1. Introduction brain functioning that trigger seizures might also have
a direct influence on cognition. Structural damage or
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Psychogenic non-epileptic seizures (PNES) are involuntary alterations due to events such as head injuries or infections
episodes of sensation, behavior, or movement that are very and imbalanced electrical activity across the brain resulting
similar to epileptic seizures (ES) but lack the electrical from seizures. 18,19 Over time, some patients may develop
activity disruption in the brain that characterizes epilepsy. malformations in different brain regions because of diverse
1
The accepted method for PNES diagnosis is prolonged causes; these malformations may disrupt the brain’s regular
video electroencephalography (vEEG) recording showing communication and function, thereby leading to cognitive
1
seizure-like behavior with no epileptic electrical correlates. impairments. 20,21 Another influencing factor is the side
Estimations suggest that 25 – 30% of patients diagnosed effects of ASM. While crucial for seizure management,
with epilepsy each year may, in fact, have PNES instead of ASM may affect cognitive processes by either slowing
ES. During this delayed diagnostic period, patients often neural transmission or modifying neurotransmitter
receive antiseizure medications (ASM), many of which levels. In addition, cognitive functions such as memory
22
are associated with negative side effects in both patients and attention may also be affected by mood changes or
with ES and those with PNES. Distinguishing between mood disorders in these patients. The cognitive deficits
2-4
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patients with ES and those with PNES poses a significant faced by ES patients can emerge from any single factor
diagnostic challenge with important implications for mentioned or a combination of them, among possible
quality of life and treatment. Furthermore, PNES and ES other causes. 6,19
5
may co-occur in 10 – 73% of PNES patients, making the
6
diagnosis even more challenging. Studies suggest that the nature of cognitive impairment
in epilepsy is intricately linked to the underlying
The etiology of PNES is complex and multidimensional. pathophysiology of the seizure disorder. Depending on
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The Diagnostic and Statistical Manual of Mental Disorders the specific type of epilepsy, reduced activation is noticeable
5 edition (DSM-5) classifies PNES as a manifestation in different brain regions, such as the right occipital lobe,
th
of functional neurological disorder, whereas the ICD-10 cerebellum, right frontal lobe, brainstem, and temporal
classifies it as a dissociative disorder. 7,8 lobe. These identified areas are thought to constitute the
Numerous factors have been investigated as potential neural basis for attention deficits, particularly within the
triggers for PNES. According to the integrative cognitive alerting network of temporal lobe epilepsy (TLE) patients. 24
9
model, overwhelming and distressing events or memories In cognitive evaluations encompassing areas such as
can destabilize cognitive and emotional systems. When attention, motor coordination, verbal/non-verbal fluency,
this occurs, the brain may become unable to process the and response inhibition, both TLE and frontal lobe epilepsy
information, causing the sensory and motor systems to (FLE) patients significantly underperformed compared to
become reflexive, eventually leading to a seizure. 10 healthy controls. Furthermore, results for FLE patients
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Most of the published research has compared PNES and were notably worse than those for TLE patients. Given
ES, often without contrasting these conditions with healthy the central role of the prefrontal cortex in attention and
controls. These studies have often found that both ES and executive functions, this could explain the anticipated
PNES patients have cognitive deficits. While such deficits deficits in attentional performance in these patients.
6,9
are a consistent finding in both groups, getting into details An investigation that employed the Stroop task
presents a complicated picture. In some specific domains, revealed that epilepsy patients are particularly hindered
studies noted superior performance in PNES patients, in conditions that evaluate response inhibition and
11
whereas others observed comparable performance between shifting when contrasted with controls. Interestingly,
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the two groups. 12-14 Binder et al. showed that when testing both FLE and TLE patients demonstrated “frontal-like”
memory and thinking skills using a specific set of tests performances. This similarity may be due to the spread of
(the Halstead–Reitan Battery), there were no performance neural disturbances in TLE patients. 27
differences between PNES and ES patients; however, both Similarly, major literature indicates that cognitive
groups performed worse than healthy individuals, except performance in individuals with PNES is generally poorer
in verbal IQ and certain tasks assessing problem-solving compared to healthy individuals. However, current
6,28
and flexibility. Conversely, Çelik et al. reported more literature presents conflicting evidence on the extent to
15
dominant attention and executive function problems in which PNES impacts cognition when compared to ES.
PNES patients when compared to ES patients. 16 Some studies have shown that patients with PNES may
The cognitive deficits in patients with ES arise from a perform better than those with ES, whereas others have
11
variety of organic brain conditions. The same changes in found no significant differences in cognitive functions

Volume 2 Issue 4 (2024) 2 doi: 10.36922/jcbp.3847