User profiles for F. Helmchen
Fritjof HelmchenProfessor of Neuroscience Verified email at hifo.uzh.ch Cited by 31694 |
Deep tissue two-photon microscopy
F Helmchen, W Denk - Nature methods, 2005 - nature.com
… For laser pulses of width τ occurring at a rate f R , the signal is enhanced by a factor of 1 /
(τ f R ) n − 1 compared to continuous-wave illumination, where n is the number of photons …
(τ f R ) n − 1 compared to continuous-wave illumination, where n is the number of photons …
[HTML][HTML] Barrel cortex function
D Feldmeyer, M Brecht, F Helmchen… - Progress in …, 2013 - Elsevier
Neocortex, the neuronal structure at the base of the remarkable cognitive skills of mammals,
is a layered sheet of neuronal tissue composed of juxtaposed and interconnected columns. …
is a layered sheet of neuronal tissue composed of juxtaposed and interconnected columns. …
Scanning fiber endoscopy with highly flexible, 1 mm catheterscopes for wide‐field, full‐color imaging
…, CJ Engelbrecht, TD Soper, F Helmchen… - Journal of …, 2010 - Wiley Online Library
… Fritjof Helmchen received his master degree in Physics from the University of Heidelberg, …
Helmchen was appointed Professor of Neurophysiology and Co-Director at the Brain …
Helmchen was appointed Professor of Neurophysiology and Co-Director at the Brain …
Resting microglial cells are highly dynamic surveillants of brain parenchyma in vivo
… (F) Length changes over time of the two protrusions P1 and P2 indicated in (E). Vertical
dashed lines mark the acquisition times of the images shown in (E). Arrows indicate protrusion …
dashed lines mark the acquisition times of the images shown in (E). Arrows indicate protrusion …
Sulforhodamine 101 as a specific marker of astroglia in the neocortex in vivo
Glial cells have been identified as key signaling components in the brain; however, methods
to investigate their structure and function in vivo have been lacking. Here, we describe a …
to investigate their structure and function in vivo have been lacking. Here, we describe a …
Fluctuations and stimulus-induced changes in blood flow observed in individual capillaries in layers 2 through 4 of rat neocortex
… For a temporal window, T, the image data F(x,t) was transformed to a reference frame that
moved with velocity c. We constructed the matrix F(x + ct, t) with t 0 < t < t 0 + T, where t 0 is the …
moved with velocity c. We constructed the matrix F(x + ct, t) with t 0 < t < t 0 + T, where t 0 is the …
[PDF][PDF] Transgenic mice for intersectional targeting of neural sensors and effectors with high specificity and performance
An increasingly powerful approach for studying brain circuits relies on targeting genetically
encoded sensors and effectors to specific cell types. However, current approaches for this …
encoded sensors and effectors to specific cell types. However, current approaches for this …
[PDF][PDF] A miniature head-mounted two-photon microscope: high-resolution brain imaging in freely moving animals
… changes in Calcium green-1 fluorescence ( F/F in the range of 40%–200%) were evoked in
the … Based on these considerations, our strategy tip was collimated with an aspheric lens (f …
the … Based on these considerations, our strategy tip was collimated with an aspheric lens (f …
High-speed in vivo calcium imaging reveals neuronal network activity with near-millisecond precision
…, D Langer, H Kasper, BM Kampa, F Helmchen - Nature …, 2010 - nature.com
Two-photon calcium imaging of neuronal populations enables optical recording of spiking
activity in living animals, but standard laser scanners are too slow to accurately determine …
activity in living animals, but standard laser scanners are too slow to accurately determine …
[PDF][PDF] Ca2+ buffering and action potential-evoked Ca2+ signaling in dendrites of pyramidal neurons
F Helmchen, K Imoto, B Sakmann - Biophysical journal, 1996 - cell.com
The effect of the fluorescent Ca2+ indicator dye Fura-2 on Ca2+ dynamics was studied in
proximal apical dendrites of neocortical layer V and hippocampal CA1 pyramidal neurons in rat …
proximal apical dendrites of neocortical layer V and hippocampal CA1 pyramidal neurons in rat …