TMS in the parietal cortex: Updating representations for attention and action

https://doi.org/10.1016/j.neuropsychologia.2005.12.007Get rights and content

Abstract

Transcranial magnetic stimulation (TMS) is one of the most recent techniques to have been used in investigations of the parietal cortex but already a number of studies have employed it as a tool in investigations of attentional and sensorimotor processes in the human parietal cortices. The high temporal resolution of TMS has proved to be a particular strength of the technique and the experiments have led to hypotheses about when circumscribed regions of parietal cortex are critical for specific attentional and sensorimotor processes. A consistent theme that runs through many reports is that of a critical contribution of parietal areas when attention or movements are re-directed and representations for attention or action must be updated.

Section snippets

Visuospatial attention: the case of visual search

In the visual search task subjects are briefly shown an array of stimuli and they are asked if it contains a particular target stimulus. The task is thought to tax attention because the relevant target must be filtered from among the irrelevant distracter stimuli in the array. The task is especially difficult when no single basic visual feature (such as colour or orientation) distinguishes the target from the distracters. In such situations it is the presence of a conjunction of features that

The timing of parietal involvement in visual search

While it might be possible to debate the significance of the timing of posterior IPS/IPL involvement in visual search it is clear that the critical time period occurs relatively late in comparison with other areas. Ashbridge et al. (1997) and Walsh et al., 1998, Walsh et al., 1999 applied single pulse TMS to the posterior IPS/IPL at 20 different SOAs between 0 ms and 200 ms. Trials on which conjunction targets were present were affected by TMS at 100 ms and target absent trials were affected by

The timing of parietal involvement in other attentional processes

A number of studies have been directly concerned with the movement of the focus of covert attention using variations of a paradigm popularized by Posner et al. (1984). In one version of the task subjects indicated detection of a target stimulus in one of two possible locations by pressing a button. On some trials a warning cue instructed subjects where the stimulus was likely to appear but on a few trials the warning was invalid. Subjects respond more slowly on such invalid trials but the

The timing of neurophysiological events in the human parietal cortex

TMS can be used to examine the progress of sensorimotor and cognitive processes in the parietal cortex on a time scale of the order of tens of milliseconds but it can also be used to investigate neurophysiological processes at an even finer time scale of the order of single milliseconds. The impact of a pulse of TMS over the primary motor cortex on muscle activity can be modulated by applying a preceding sub-threshold pulse called a “conditioning” pulse. The conditioning pulse does not in

Localization within the parietal cortex

The much vaunted temporal specificity of TMS has been exploited to gain novel insights into the timing of attentional processes in the parietal cortex. TMS only affects neural activity in a spatially limited region of tissue (Valero-Cabre, Payne, Rushmore, Lomber, & Pascual-Leone, 2005; Walsh & Cowey, 2000; Fig. 4) but it has produced fewer insights into localization of function within the parietal cortex. In contrast fMRI has shown that regional differences in activation within the parietal

Spatial reference frames in the parietal cortex

The disruptive effects of parietal TMS on visuospatial task performance are restricted to particular reference frames. Bjoertomt, Cowey, and Walsh (2002) gave normal subjects a line bisection task often used to detect visuospatial neglect. Subjects had to judge whether long horizontal lines (about 36° of visual angle) were transected by a short vertical line at the midpoint, or whether the horizontal line was shifted slightly (1°) to the left or right. The line was presented at a distance of

Parietal cortex and eye movements

The same regions of parietal cortex that are involved in covert attentional processes are also active when overt eye movements are made (Corbetta et al., 1998; Nobre, Gitelman, Dias, & Mesulam, 2000) so it is not surprising that parietal TMS also affects eye movements (Elkington, Kerr, & Stein, 1992; Kapoula, Isotalo, Muri, Bucci, & Rivaud-Pechoux, 2001; Terao, Fukuda, et al., 1998; Zangemeister, Canavan, & Hoemberg, 1995). Just as TMS over the posterior IPS/IPL region disrupts updating of the

Parietal cortex and the control of limb movement: updating reaching movements

While a number of parietal regions are concerned with visuospatial and attentional processes and overt eye movements there are a number of other regions that are more closely identified with limb movements. In the macaque the anterior intraparietal (AIP) area, like LIP, is in the IPL but situated more anteriorly (Sakata et al., 1999). A similar region is also found in the anterior part of the human IPL (Binkofski et al., 1998; Grefkes & Fink, 2005; Grefkes, Weiss, Zilles, & Fink, 2002). A

A general role for the parietal cortex in the updating of movements?

Despite their influence the reliability and interpretation of the findings have been called into question. Johnson and Haggard (2005) have reported difficulty in finding impaired reaching adjustments when TMS is applied over the parietal cortex. Roy, Stefanini, Pavesi, & Gentilucci (2004) have reported that the problems of an optic ataxic patient occur early during a movement and were not limited to the final adjustments before reaching a target.

On the other hand there appears to be an emerging

Re-directing motor intentions

Theories of motor control based on ideas of feedforward control and the use of internal models emphasize that it is the expected feedback that should be associated with an intended position of the limb that is compared with actual feedback or a target position. It is therefore not surprising that TMS does not just impair movements when the course of an ongoing movement needs to be changed but it also impairs movements when changes need to be made to an intended movement (Rushworth, Ellison, et

Eye-hand coordination and the parietal cortex

Disruption of on-line correction during limb movement has been reported after TMS of both the SPL (Della-Maggiore et al., 2004, Glover et al., 2005) and the IPL (Desmurget et al., 1999, Tunik et al., 2005). It is not clear if the results can be interpreted in terms of an MIP-like system in the SPL and an AIP-like system in the IPL that may be concerned with proximal and distal movements, respectively. Hand aperture has been reported to be disrupted after TMS to both the IPL and the SPL (Glover

Conclusion

TMS is probably the most recent technique to have been employed in investigations of the human parietal cortex. There has been an emphasis on visuospatial and oculomotor function in the most posterior parietal regions but a coherent pattern to the results of TMS investigations of arm movement control is also emerging in other regions. A consistent theme that runs through several of the studies is that TMS particularly disrupts performance when eye or limb movements occur, or even if the

References (159)

  • S. Gobel et al.

    The mental number line and the human angular gyrus

    Neuroimage

    (2001)
  • H. Grea et al.

    A lesion of the posterior parietal cortex disrupts on-line adjustments during aiming movements

    Neuropsychologia

    (2002)
  • C. Grefkes et al.

    Crossmodal processing of object features in human anterior intraparietal cortex: An fMRI study implies equivalencies between humans and monkeys

    Neuron

    (2002)
  • S.R. Jackson et al.

    Where the eye looks, the hand follows; limb-dependent magnetic misreaching in optic ataxia

    Current Biology

    (2005)
  • H. Johnson et al.

    Motor awareness without perceptual awareness

    Neuropsychologia

    (2005)
  • S. Kastner et al.

    The neural basis of biased competition in human visual cortex

    Neuropsychologia

    (2001)
  • S. Kastner et al.

    Increased activity in human visual cortex during directed attention in the absence of visual stimulation

    Neuron

    (1999)
  • G. Koch et al.

    rTMS evidence of different delay and decision processes in a fronto-parietal neuronal network activated during spatial working memory

    Neuroimage

    (2005)
  • P. Malhotra et al.

    Impaired spatial working memory: One component of the visual neglect syndrome?

    Cortex

    (2004)
  • J. Miklossy

    The geniculocalcarine pathway in man, and some putative rostral visual areas involved in visuo-spatial attention

  • K.R. Mills et al.

    Magnetic brain stimulation with a double coil: The importance of coil orientation

    Electroencephalography and Clinical Neurophysiology

    (1992)
  • D.J. Mort et al.

    Differential cortical activation during voluntary and reflexive saccades in man

    Neuroimage

    (2003)
  • R.M. Muri et al.

    Hemispheric asymmetry in cortical control of memory-guided saccades A transcranial magnetic stimulation study

    Neuropsychologia

    (2000)
  • A.C. Nobre et al.

    Covert visual spatial orienting and saccades: Overlapping neural systems

    Neuroimage

    (2000)
  • A.C. Nobre et al.

    Filtering of distractors during visual search studied by positron emission tomography

    Neuroimage

    (2002)
  • A.C. Nobre et al.

    Brain activations during visual search: Contributions of search efficiency versus feature binding

    Neuroimage

    (2003)
  • M. Okamoto et al.

    Three-dimensional probabilistic anatomical cranio-cerebral correlation via the international 10–20 system oriented for transcranial functional brain mapping

    Neuroimage

    (2004)
  • AEEGS

    American Electroencephalographic Society guidelines for standard electrode placement position nomenclature

    Journal of Clinical Neurophysiology

    (1991)
  • R.A. Andersen et al.

    Intentional maps in posterior parietal cortex

    Annual Review of Neuroscience

    (2002)
  • S.V. Astafiev et al.

    Functional organization of human intraparietal and frontal cortex for attending, looking, and pointing

    Journal of Neuroscience

    (2003)
  • C. Bard et al.

    Deafferentation and pointing with visual double-step perturbations

    Experimental Brain Research

    (1999)
  • A.T. Barker

    The history and basic principles of magnetic nerve stimulation

    Electroencephalography and Clinical Neurophysiology

    (1999)
  • S. Bestmann et al.

    Functional MRI of the immediate impact of transcranial magnetic stimulation on cortical and subcortical motor circuits

    European Journal of Neuroscience

    (2004)
  • N.P. Bichot et al.

    Parallel and serial neural mechanisms for visual search in macaque area V4

    Science

    (2005)
  • F. Binkofski et al.

    Human anterior intraparietal area subserves prehension: A combined lesion and functional MRI activation study

    Neurology

    (1998)
  • O. Bjoertomt et al.

    Spatial neglect in near and far space investigated by repetitive transcranial magnetic stimulation

    Brain

    (2002)
  • O. Blanke et al.

    Linking out-of-body experience and self processing to mental own-body imagery at the temporoparietal junction

    Journal of Neuroscience

    (2005)
  • D. Boussaoud et al.

    Primate frontal cortex: Neuronal activity following attentional versus intentional cues

    Experimental Brain Research

    (1993)
  • C.A. Buneo et al.

    Direct visuomotor transformations for reaching

    Nature

    (2002)
  • M.V. Chafee et al.

    Matching patterns of activity in primate prefrontal area 8a and parietal area 7ip neurons during a spatial working memory task

    Journal of Neurophysiology

    (1998)
  • M.V. Chafee et al.

    Inactivation of parietal and prefrontal cortex reveals interdependence of neural activity during memory-guided saccades

    Journal of Neurophysiology

    (2000)
  • C.D. Chambers et al.

    Fast and slow parietal pathways mediate spatial attention

    Nature Neuroscience

    (2004)
  • P.A. Chouinard et al.

    Modulating neural networks with transcranial magnetic stimulation applied over the dorsal premotor and primary motor cortices

    Journal of Neurophysiology

    (2003)
  • J.D. Connolly et al.

    FMRI evidence for a ’parietal reach region’ in the human brain

    Experimental Brain Research

    (2003)
  • C. Constantinidis et al.

    Neuronal responses in area 7a to multiple stimulus displays: II Responses are suppressed at the cued location

    Cerebral Cortex

    (2001)
  • C. Constantinidis et al.

    Neuronal responses in area 7a to multiple-stimulus displays: I neurons encode the location of the salient stimulus

    Cerebral Cortex

    (2001)
  • M. Corbetta et al.

    Control of goal-directed and stimulus-driven attention in the brain

    Nature Reviews. Neuroscience

    (2002)
  • M. Corbetta et al.

    Voluntary orienting is dissociated from target detection in human posterior parietal cortex

    Nature Neuroscience

    (2000)
  • M. Corbetta et al.

    Neural basis and recovery of spatial attention deficits in spatial neglect

    Nature Neuroscience

    (2005)
  • E. Corthout et al.

    Transcranial magnetic stimulation. Which part of the current waveform causes the stimulation?

    Experimental Brain Research

    (2001)
  • Cited by (0)

    View full text