Brain substrates for automatic retrieval of value memory in the primate basal ganglia

Our behavior is often carried out automatically. Automatic behavior can be guided by past experiences, such as learned values associated with objects. Passive-viewing and free-viewing tasks with no immediate outcomes provide a testable condition in which monkeys and humans automatically retrieve value memories and perform habitual searching. Interestingly, in these tasks, caudal regions of the basal ganglia structures are involved in automatic retrieval of learned object values and habitual gaze. In contrast, rostral regions do not participate in these activities but instead monitor the changes in outcomes. These findings indicate that automatic behaviors based on the value memories are processed selectively by the caudal regions of the primate basal ganglia system. Understanding the distinct roles of the caudal basal ganglia may provide insight into finding selective causes of behavioral disorders in basal ganglia disease.

Biotin–Thiamine Responsive Basal Ganglia Disease Presented as Intractable Seizure in a 1-Month-Old Infant

Biotin–thiamine responsive basal ganglia disease is a neurometabolic disorder, seen in children presenting with encephalopathy, seizures, and positive family history. The disease is diagnosed based on typical magnetic resonance imaging (MRI) findings and whole exome sequencing but may be initially misdiagnosed as a mitochondrial encephalopathy or an inborn error of metabolism (IEM). We describe the case of an infant who presented with uncontrolled seizures and encephalopathy, responding to high doses of thiamine and biotin. Life-long supplementation of biotin (2–10 mg/kg/day) and thiamine (200–300 mg/day) improves the symptomatology and prevents relapse. Outcomes of the disease are heterogeneous, ranging in scope from complete remission to severe neurological sequelae.