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Styr, B.

Publications and source records attributed to Styr, B..

2 recordsLinked to original sources

Motor Cortical Computations Underlying Natural Dexterous Movement in Freely Flying Bats

Elucidating the neural computations underlying natural, complex movement remains a fundamental challenge in neuroscience. Bat flight presents a formidable motor control challenge, requiring the use of hand-like wings whose many degrees of freedom must be precisely coordinated to enable rapid three-dimensional maneuvers. Here we performed large-scale wireless recordings of neuronal ensembles from the wing motor cortex of freely flying bats using Neuropixels probes, alongside detailed 3D pose tracking of wing kinematics. Despite the complexity of flight control, bats repeatedly executed highly accurate flights through precise adjustments of individual wingbeats. Surprisingly, motor cortical activity was not dominated by the global wingbeat cycle. Instead, individual neurons were sparsely active, exhibiting mixed selectivity for specific flight kinematics combined with variable entrainment to the wingbeat phase reaching millisecond-scale precision. This yielded a high-dimensional population regime driven by low shared variance across wingbeats, with successive wingbeats occupying distinct neural population states. Our findings reveal that during complex natural behavior the mammalian motor cortex operates in a high-dimensional computational regime that challenges prevailing views of motor cortical computation and underscores the importance of studying ethologically relevant behaviors to uncover neural principles governing brain function.

neuroscience↗

IGF1 Receptor Regulates Upward Firing Rate Homeostasis via the Mitochondrial Calcium Uniporter

Regulation of firing rate homeostasis constitutes a fundamental property of central neural circuits. While intracellular Ca2+ has long been hypothesized to be a feedback control signal, the molecular machinery enabling network-wide homeostatic response remains largely unknown. Here we show that deletion of insulin-like growth factor-1 receptor (IGF1R), a well-known regulator of neurodevelopment and ageing, limits firing rate homeostasis in response to inactivity, without altering the baseline firing rate distribution. Disruption of both synaptic and intrinsic homeostatic plasticity contributed to deficient firing rate homeostatic response. At the cellular level, a fraction of IGF1Rs was localized in mitochondria with the mitochondrial calcium uniporter complex (MCUc). IGF1R deletion suppressed spike burst-evoked mitochondrial Ca2+ (mitoCa2+) by weakening mitochondria-to-cytosol Ca2+ coupling. MCUc overexpression in IGF1R-deficient neurons rescued the deficits in spike-to-mitoCa2+ coupling and firing rate homeostasis. Our findings highlight IGF1R as a key regulator of the integrated homeostatic response by tuning mitochondrial temporal filtering. Decline in mitochondrial reliability for burst transfer may drive dysregulation of firing rate homeostasis in ageing and brain disorders associated with aberrant IGF1R / MCUc signaling.

neuroscience↗