Dr. Barbara Händel
If sensory input reaches a certain threshold it normally leads to perception. With my research I try to understand the role of oscillatory brain activity in how visual sensory input is processed, transmitted and perceived.
In most cases sensory input and perception are tightly correlated making it impossible to decide if measured brain activity depicts the processing of the sensory input or the perception of it. It therefor is crucial to disentangle the sensory input from the perceptual outcome. There are several possibilities:
· near threshold stimuli generate a certain percept at one point but fail to at another moment
· changing the attention for a given stimulus can modulate the perceptual outcome
· illusionary stimuli will generate percept without corresponding sensory input
Using these possibilities, I investigate brain oscillations in different frequency bands including delta, theta, alpha and gamma oscillations as well as their interactions recorded by means of electro- and magnetoencephalography (EEG, MEG).
Händel, B., & Jensen, O. (2014). Spontaneous local alpha oscillations predict motion-induced blindness. European Journal of Neuroscience, 40 (9), 3371-3379.
van Leeuwen, TM., Hagoort, P., & Händel, B. (2013). Real color captures attention and overrides spatial cues in grapheme-color synesthetes but not in controls. Neuropsychologia, 51 (10), 1802-1813.
Händel, B., Haarmeier, T., & Jensen, O. (2011). Alpha Oscillations Correlate with the Successful Inhibition of Unattended Stimuli. Journal of Cognitive Neuroscience 23(9), 2494–2502.
Haegens, S., Händel, B., & Jensen O. (2011). Top-Down Controlled Alpha Band Activity in Somatosensory Areas Determines Behavioral Performance in a Discrimination Task, The Journal of Neuroscience, 31(14):5197–5204.
Händel, B., & Haarmeier, T. (2009). Cross- frequency coupling of brain oscillations indicates the success in visual motion discrimination. Neuroimage, 45: 1040–1046.
Händel, B., Lutzenberger, W., Thier, P., & Haarmeier, T. (2008). Selective Attention Increases the Dependency of Cortical Responses on Visual Motion Coherence in Man. Cerebral Cortex, 18: 2902-2908.
Händel, B., Lutzenberger, W., Thier, P., & Haarmeier, T. (2007). Opposite dependencies on visual motion coherence in human area MT+ and early visual cortex. Cererbal Cortex, 17(7):1542-9.
Tikhonov, A.*, Händel, B.*, Haarmeier, T., Lutzenberger, W., & Thier, P. (2007). Gamma oscillations underlying the visual motion after-effect. Neuroimage, 38: 708-719.