Cortical laminar resting‐state signal fluctuations scale with the hypercapnic blood oxygenation level‐dependent response

Laminar Cortical Architecture

Revisit Nonlinearity in Blood-oxygenation-level-dependent Signal

Introduction The majority of studies investigating the linearity of the BOLD signal suggested existence of significant nonlinearity. In these studies, repeated stimuli led to successively smaller BOLD amplitudes and delayed BOLD onset latencies when the inter-stimulus interval (ISI) is shorter than a few seconds. The mechanism of nonlinearity in the BOLD signal remains unknown, partially becaus...

Laminar processing in the visual cortical column.

Sensory regions of neocortex are organized as arrays of vertical columns composed of cells that share similar response properties, with the orientation columns of the cat's visual cortex being the best known example. Interest in how sensitivity to different stimulus features first emerges in the columns and how this selectivity is refined by subsequent processing has fueled decades of research....

Spontaneous low-frequency blood oxygenation level-dependent fluctuations and functional connectivity analysis of the 'resting' brain.

Functional magnetic resonance imaging techniques using the blood oxygenation level-dependent (BOLD) contrast are widely used to map human brain function by relating local hemodynamic responses to neuronal stimuli compared to control conditions. There is increasing interest in spontaneous cerebral BOLD fluctuations that are prominent in the low-frequency range (<0.1 Hz) and show intriguing spati...

Hypercapnic blood pressure response is greater during the luteal phase of the menstrual cycle.

We investigated the cardiovascular responses to acute hypercapnia during the menstrual cycle. Eleven female subjects with regular menstrual cycles performed hypercapnic rebreathing tests during the follicular and luteal phases of their menstrual cycles. Ventilatory and cardiovascular variables were recorded breath by breath. Serum progesterone and estradiol were measured on each occasion. Serum...