Publications 1997
Eimer, M. (1997). An event-related potential (ERP) study of transient and sustained visual attention to color and form. Biological Psychology, 44, 143-160.
Eimer, M. (1997). Attentional selection and attentional gradients: An alternative method for studying transient visual-spatial attention. Psychophysiology, 34, 365-376.
Abstract: Two experiments are reported that employed an alternative method for studying transient visual-spatial attention. Instead of using precues, attention was manipulated by presenting most stimuli sequentially at predictable locations. In Experiment 1, most stimuli appeared in a regular clockwise or counterclock-wise order, but some were separated by one or both visual meridians from the expected location. In Experiment 2, most stimuli were presented succesively along the horizontal meridian, and some stimuli were separated by one, two, or three positions from the expected location. Faster RTs and larger posterior P1 and N1 components as well as enhanced negativities at midline electrodes were found for expected location relative to unexpected location stimuli. These effects were partially modulated by the distance of unexpected stimuli from the current focus of attention, suggesting the existence of attentional gradients. Moreover, the data suggest that the direction of previous attentional shifts and the visual meridians play an important role for spatial attention.
Eimer, M. (1997). The Lateralized Readiness Potential as an on-line measure of automatic response activation in S-R compatibility situations. In B. Hommel & W. Prinz (Eds.). Theoretical issues in stimulus-response compatibility. Advances in Psychology, 118. Amsterdam: Elsevier (pp. 51-73).
Abstract: The Lateralized Readiness Potential (LRP) is an electrophysiological indicator of partial response activation. A number of experiments are reported where the LRP was measured in order to obtain evidence for automatic response activation processes elicited in S-R compatibility situations. In the first series of experiments, a cue-target paradigm was employed and the LRP was measured in response to the cue. When arrows were used as cues, an early activation of the response corresponding to the arrow’s direction was observed, which was largely independent of objective cue-response contingencies, presumably indicating an involuntary process. No such effect was observed when non-spatial cues (colored squares) were used or when the cue was unattended. A second series of experiments was conducted to demonstrate that due to systematic confoundations of motor and non-motor asymmetries, LRPs elicited by lateralized target stimuli cannot be interpreted unequivocally in terms of response activation. Therefore, an alternative paradigm is introduced where colored arrows are used as target stimuli, with arrow color relevant and arrow direction irrelevant for response selection. The LRPs revealed an early activation of responses spatially congruent to the arrow’s direction. Overall, the experiments show that when the various confoundations of motor and non-motor effects on the LRP are effectively dealt with, the LRP may be a useful tool for studying automatic response activation processes in S-R compatibility situations.
Eimer, M. (1997). Uninformative symbolic cues may bias visual-spatial attention: Behavioral and electrophysiological evidence. Biological Psychology, 46, 67-71.
Schlaghecken, F. & Eimer, M. (1997). The influence of subliminally presented primes on response preparation. Sprache & Kognition, 16, 166-175.
Abstract: In a RT study the influence of masked primes on behavioural performance was investigated under different presentation conditions. Masked primes were presented prior to target stimuli. Primes were either identical to the target (compatible trials), or identical to a target mapped to the opposite response (incompatible trials). Mask target SOA was varied in steps of 32 ms, ranging from 0 ms to 128 ms. Additionally, stimuli were presented either at fixation or peripherally. Results suggest that primes that are not consciously perceived nevertheless trigger a response preparation that is later inhibited: With short mask-target SOAs as well as with peripheral primes, RTs were slower in incompatible than on compatible trials. With longer SOAs and central primes, the reversed pattern of results was obtained. It is argued that the effects of masked primes on motor activation reflect the activity of a visuomotor control system that utilises stimulus information independent of conscious perception in order to prepare the appropriate response.
Schroger, E., & Eimer, M. (1997). Covert spatial orienting in audition: ‘Cost-Benefit’ analyses of reaction times and event-related potentials. The Quarterly Journal of Experimental Psychology, 50A, 457-474.
Publications 1996
Eimer, M. (1996). ERP modulations indicate the selective processing of visual stimuli as a result of transient and sustained spatial attention. Psychophysiology, 33, 13-21.
Abstract: Two experiments investigated selective processing as a result of transient and sustained visual-spatial attention. In Experiment 1, attention was cued on a trial by trial basis and event related brain potentials were measured to stimuli preceded by valid, invalid, or neutral symbolic precues. Trial validity had only small effects on posterior P1 and N1 components. At midline electrodes, an enhanced negativity for valid as compared to invalid trials was present, which appeared to reflect initial processing costs for invalid trials followed by an additional processing benefit for valid trials. Experiment 2 investigated whether these effects are specific for transient spatial attention by comparing transient and sustained attention conditions. No indication of early processing costs was found in the latter case.
Eimer, M. (1996). The N2pc component as an indicator of attentional selectivity. Electroencephalograpy and Clinical Neurophysiology, 99, 225-234.
Eimer, M., Goschke, T., Schlaghecken, F., & Stürmer, B. (1996). Explicit and implicit learning of event sequences: Evidence from event-related brain potentials. Journal of Experimental Psychology: Learning, Memory, & Cognition, 22, 970-987.
Schroger, E., & Eimer, M. (1996). Effects of lateralized cues on the processing of lateralized auditory stimuli. Biological Psychology, 43, 203-226.
