The attention-emotion relationship in patients with psychogenic non-epileptic seizures: a pilot study

Recognition of emotional signals is a critical component of human interaction, since it is our understanding of the emotional states of others that guides our behavioral responses and interpersonal relationships (Adolphs, 2009). Of these signals, facial expressions provide the greatest amount of emotional cues useful to recognize basic emotions in others, followed by gestures, bodily postures, and prosody (Bonora et al., 2011).

Studies on animals and humans have revealed that the recognition of emotional facial expressions involves a neural circuitry that includes the occipitotemporal neocortex, the orbitofrontal cortex, the right frontoparietal cortices, and the amygdala (LeDoux, 1996; Adolphs et al., 1994; Adolphs, 2002).

In particular, the amygdala is known to be a key structure in the processing of facial expression, as demonstrated by the impairment in recognition of facial emotional expressions found in human patients with bilateral lesion in this structure (Adolphs et al., 1994). Hence, given the important role played by the antero-medial temporal lobe in decoding emotions, mental states, and beliefs of others, several studies have assessed the recognition of emotional signals in patients with temporal lobe epilepsy (TLE). TLE is the most common form of focal epilepsy and is frequently characterized by lesions or gliosis/atrophy involving the temporal regions (Williamson et al., 1993; Wieser, 2004). Thus, antero-medial temporal lobe resection is considered the standard treatment for TLE (Wiebe et al., 2001), with the 2/3 of patients that result seizure-free after the lobectomy (Engel et al., 2003). Seizures are in fact provoked by abnormal electrical changes starting from one region, or several regions, within the temporal lobe, often including the amygdala (Bartolomei et al., 2001).

In particular, in medial frontal lobe epilepsy (MTLE), these abnormal electrical changes are thought to occur in the inner parts of the temporal cortices, and the clinical manifestations appear as the direct reflection of pathological changes in these structures (Benbadis et al., 2003). Indeed, patients with MTLE often show ictal emotional disturbances, such as fear or anxiety, and interictal psychiatric modifications (Piazzini & Changer, 2001; Perini et al., 1996).

Moreover, it has been demonstrated that MTLE patients have an increased rate of psychiatric disturbances compared to patients with other types of epilepsy (Hermann et al., 2000; Perini et al., 1996). It is hence possible that electrical changes in the structures of the inner temporal lobe may induce affective modifications (Perini et al., 1996; Meletti et al., 2006), responsible for emotional (Baker, 1997), behavioral (Brandt et al., 1985), cognitive (Frisk & Milner, 1990), and social impairments found in these patients.

It is not clear, however, if these psychological difficulties are caused by medication, psychological, and/or social factors or by brain lesions caused by epilepsy itself, then several researchers have assessed emotion processing in patients with TLE. The most studied emotional process, for the reasons indicated above, is the recognition of emotional facial expressions. [...]