BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20250312T181142EDT-85473z1rUi@132.216.98.100 DTSTAMP:20250312T221142Z DESCRIPTION:Established in 1935\, the Hughlings Jackson Lecture is The Neur o’s premier scientific lecture. It honours the legacy of British neurologi st John Hughlings Jackson (1835-1911) who pioneered the development of neu rology as a medical specialty. A reception will follow.\n\nTo register: co ming soon\n\nTo view virtually: coming soon\n\nTalk: The Basal Ganglia and the Motivation to Act\n\nSpeaker: Ann Graybiel\, PhD\n Institute Professor \, Department of Brain and Cognitive Sciences\, MIT\n\nAbstract: It is uni versally recognized that the basal ganglia are implicated in major hypokin etic and hyperkinetic extrapyramidal motor disorders. But a shift in think ing about the basal ganglia is occurring with the realization that their r each extends beyond the control of movement to modulation of mood and cogn ition. In this lecture\, I will focus on experimental work that favors the se non-classical views and introduce evidence that previously unrecognized links between the striatum and the dopamine-containing neurons of the sub stantia nigra may be crucial to these non-classical functions of the basal ganglia. Foundational work has shown that a balance between two great bas al ganglia output pathways\, the Direct-D1 and Indirect-D2 pathways\, is n ecessary for normal movement. Imbalance favoring the canonical D-1 ‘Go’ pa thway is seen in hyperkinetic disorders including Huntington’s disorder\, and imbalance favoring the canonical D-2 ‘NoGo’ pathway leads to hypokinet ic disorders including Parkinson’s disease. Thus operationally\, an agonis t-antagonist balance is thought to regulate and coordinate movements\, alo ng with additional cooperative links between these. These pathways lead to the motor output nuclei of the basal ganglia. Quite outside this model is the nigro-striato-nigral loop\, which is a target of Parkinson’s disease and has been implicated in a range of neuropsychiatric disorders. With the explosion of new methods in experimental neuroscience it now has been pos sible to catch the first glimpses of how these two circuit organizations c ould be aligned. Remarkably\, it turns out that the canonical Direct and I ndirect pathways are paralleled by a non-canonical pair of Direct and Indi rect pathways that target not the motor outputs of the basal ganglia prope r\, but the dopamine-containing neurons of the substantia nigra. These new ly recognized pathways arise from specialized\, widely distributed modules in the striatum called striosomes\, first identified in the human brain. Our evidence to date suggests that the striosomal pathways closely mimic t he canonical pathways\, except for their crucial differences in outputs ta rgets. They seem to work in opposition to each other and have opposite Go- D1 NoGo-D2 polarities. These results are very new\, but accumulating evide nce already points to the striosomes as being functionally important for r einforcement-based learning\, for behavioral engagement\, for cost-benefit approach-avoidance decision-making\, and for switching or maintaining moo d and bodily states\, all concordant with evidence that the striosomal cir cuits receive inputs from limbic system-related regions. Together\, these findings can help to forge new models of basal ganglia function that inclu de motivation and mood as parts of a network of forebrain control circuits interacting with dopamine and other neuromodulators to influence behavior al and cognitive action.\n DTSTART:20251113T210000Z DTEND:20251113T220000Z LOCATION:Jeanne Timmins Amphitheatre\, Montreal Neurological Institute\, CA \, QC\, Montreal\, H3A 2B4\, 3801 rue University SUMMARY:2025 Hughlings Jackson Lecture: The Basal Ganglia and the Motivatio n to Act URL:/medhealthsci-gradstudies/channels/event/2025-hugh lings-jackson-lecture-basal-ganglia-and-motivation-act-362529 END:VEVENT END:VCALENDAR