To date neurobiological interest in the behavioral consequences of epilepsy has been concerned primarily with the neuropsychology of temporal lobe epilepsy (TLE) and of mesial temporal lobe epilepsy (mTLE) in particular. In epilepsy several factors can be discerned, which can lead to dynamic and principally reversible changes in the patient's behaviors and mood states. The patient with epilepsy must always be seen in his or her state relative to seizures. Epileptic activity can affect distant brain areas and cause cognitive and behavioral problems beyond the primary lesion. Antiepileptic drugs may have positive or negative psychotropic side effects, and can show incompatibilities in the individual patient. Very special behavioral and neuropsychological conditions are met during nonconvulsive status epilepticus (NCSE). The chapter concludes that in temporal and frontal lobe epilepsy dysfunctional behaviors can be discerned which characteristically correspond to the affected brain regions.

Imaging and lesion studies have identified cerebral networks associated with social cognitive functions which are frequently affected in patients with temporal or frontal lobe epilepsies. Processing of emotional information plays an important role in many aspects of cognition, including decision-making, memory, and attention. The perception and expression of emotional information and theory of mind (ToM) abilities have been investigated in numerous studies in a variety of patient groups and healthy persons using a number of experimental paradigms and tests. The chapter presents short descriptions and behavioral data from a variety of tests in order to reveal their differences and to highlight recent developments and research perspectives. Mesial temporal lobe epilepsy (MTLE) is the most prevalent focal epilepsy. Structure-function analyses have also shown an association between impairments in the recognition of facial expressions, especially of fear and reduced fMRI activity in patients with early onset right-sided TLE.

Hippocampal sclerosis (HS) has been recognized as the most commonly encountered pathological substrate of mesial temporal lobe epilepsy (MTLE). The pathological condition was initially described by early neuropathologists based on postmortem material. Studies in familial MTLE are also important for better understanding of the pathogenesis of HS. HS identified by magnetic resonance imaging (MRI) has been associated with poor medical control of seizures. Neurologic examination is usually normal except for facial asymmetry and memory deficits, which are material-specific for the side of ictal onset. Interictal electroencephalogram (EEG) findings in patients with MTLE typically include unilateral or bilaterally independent mesial temporal spikes, best seen with basal derivations. Treatment should start with a first-line antiepileptic drug (AED) in monotherapy, the dose of which is increased until seizure freedom or the occurrence of side effects such as tiredness, dizziness, diploplia, or gait disturbance.