The OFC is divided into ventrolateral (VLO), lateral (LO), medial (MO) and dorsolateral (DLO) regions. Using highly specific techniques to manipulate circuitry, such as optogenetics, the OFC has been implicated in OCD like behaviors. Destruction of the OFC through acquired brain injury typically leads to a pattern of disinhibited behaviour. Examples include swearing excessively, hypersexuality, poor social interaction, compulsive gambling, drug use (including alcohol and tobacco), and poor empathising ability. Disinhibited behaviour by patients with some forms of frontotemporal dementia is thought to be caused by degeneration of the OFC. When OFC connections are disrupted, a number of cognitive, behavioral, and emotional consequences may arise. Research supports that the main disorders associated with dysregulated OFC connectivity/circuitry center around decision-making, emotion regulation, and reward expectation. A recent multi-modal human neuroimaging study shows disrupted structural and functional connectivity of the OFC with the subcortical limbic structures (e.g., amygdala or hippocampus) and other frontal regions (e.g., dorsal prefrontal cortex or anterior cingulate cortex) correlates with abnormal OFC affect (e.g., fear) processing in clinically anxious adults. One clear extension of problems with decision-making is drug addiction/substance dependence, which can result from disruption of the striato-thalamo-orbitofrontal circuit. Attention deficit hyperactivity disorder (ADHD) has also been implicated in dysfunction of neural reward circuitry controlling motivation, reward, and impulsivity, including OFC systems. Other disorders of executive functioning and impulse control may be affected by OFC circuitry dysregulation, such as obsessive–compulsive disorder and trichotillomania  Some dementias are also associated with OFC connectivity disruptions. The behavioral variant of frontotemporal dementia is associated with neural atrophy patterns of white and gray matter projection fibers involved with OFC connectivity. Finally, some research suggests that later stages of Alzheimer's Disease be impacted by altered connectivity of OFC systems. Orbitofrontal epilepsy is rare, but does occur. The presentation of OFC epilepsy is fairly diverse, although common characteristics include being sleep related, automatisms, and hypermotor symptoms. One review reported that auras were generally not common or nonspecific, while another reported that OFC epilepsy was associated auras involving somatosensory phenomenon and fear. The visual discrimination test has two components.