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The functional role of the inferior parietal lobe in the dorsal and ventral stream dichotomy.

Singh-Curry V, Husain M - Neuropsychologia (2008)

Bottom Line: Some recent proposals have attempted to integrate aspects of IPL function that were not hitherto dealt with well, such as differences between the left and right hemisphere and the role of the right IPL in responding to salient environmental events.Here we critically appraise existing proposals regarding the functional architecture of the visual system, with special emphasis on the role of this region, particularly in the right hemisphere.We review evidence that shows the right IPL plays an important role in two different, but broadly complementary, aspects of attention: maintaining attentive control on current task goals as well as responding to salient new information or alerting stimuli in the environment.

View Article: PubMed Central - PubMed

Affiliation: UCL Institute of Cognitive Neuroscience, London, United Kingdom.

ABSTRACT
Current models of the visual pathways have difficulty incorporating the human inferior parietal lobe (IPL) into dorsal or ventral streams. Some recent proposals have attempted to integrate aspects of IPL function that were not hitherto dealt with well, such as differences between the left and right hemisphere and the role of the right IPL in responding to salient environmental events. However, we argue that these models also fail to capture adequately some important findings regarding the functions of the IPL. Here we critically appraise existing proposals regarding the functional architecture of the visual system, with special emphasis on the role of this region, particularly in the right hemisphere. We review evidence that shows the right IPL plays an important role in two different, but broadly complementary, aspects of attention: maintaining attentive control on current task goals as well as responding to salient new information or alerting stimuli in the environment. In our view, findings from functional imaging, electrophysiological and lesion studies are all consistent with the view that this region is part of a system that allows flexible reconfiguration of behaviour between these two alternative modes of operation. Damage to the right IPL leads to deficits in both maintaining attention and also responding to salient events, impairments that contribute to hemineglect, the classical syndrome that follows lesions of this region.

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Related in: MedlinePlus

Activation sites associated with target related salience. Meta-analysis (performed in MRIcro–www.sph.sc.edu/comd/rorden/mricro) of brain activation sites associated with target detection during the oddball paradigm in healthy control subjects. Only right hemisphere frontal and parietal regions are shown.
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fig3: Activation sites associated with target related salience. Meta-analysis (performed in MRIcro–www.sph.sc.edu/comd/rorden/mricro) of brain activation sites associated with target detection during the oddball paradigm in healthy control subjects. Only right hemisphere frontal and parietal regions are shown.

Mentions: In healthy control subjects, during target detection using this paradigm, the cortical areas most consistently activated on functional imaging are the right sided IPL, IPS, TPJ and frontal regions (Bunzeck & Duzel, 2006; Clark et al., 2000; Foucher et al., 2004; Gur et al., 2007; Huang et al., 2005; Kiehl et al., 2001, 2005; Lagopoulos et al., 2006; Linden et al., 1999; Marois et al., 2000; Williams et al., 2007). This is illustrated in Fig. 3, which plots right hemisphere activation foci obtained in a meta-analysis we performed of these studies (listed in Table 2). The investigations included in this analysis employed the oddball paradigm using stimuli of any sensory modality, but occurring at a single location only.


The functional role of the inferior parietal lobe in the dorsal and ventral stream dichotomy.

Singh-Curry V, Husain M - Neuropsychologia (2008)

Activation sites associated with target related salience. Meta-analysis (performed in MRIcro–www.sph.sc.edu/comd/rorden/mricro) of brain activation sites associated with target detection during the oddball paradigm in healthy control subjects. Only right hemisphere frontal and parietal regions are shown.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2697316&req=5

fig3: Activation sites associated with target related salience. Meta-analysis (performed in MRIcro–www.sph.sc.edu/comd/rorden/mricro) of brain activation sites associated with target detection during the oddball paradigm in healthy control subjects. Only right hemisphere frontal and parietal regions are shown.
Mentions: In healthy control subjects, during target detection using this paradigm, the cortical areas most consistently activated on functional imaging are the right sided IPL, IPS, TPJ and frontal regions (Bunzeck & Duzel, 2006; Clark et al., 2000; Foucher et al., 2004; Gur et al., 2007; Huang et al., 2005; Kiehl et al., 2001, 2005; Lagopoulos et al., 2006; Linden et al., 1999; Marois et al., 2000; Williams et al., 2007). This is illustrated in Fig. 3, which plots right hemisphere activation foci obtained in a meta-analysis we performed of these studies (listed in Table 2). The investigations included in this analysis employed the oddball paradigm using stimuli of any sensory modality, but occurring at a single location only.

Bottom Line: Some recent proposals have attempted to integrate aspects of IPL function that were not hitherto dealt with well, such as differences between the left and right hemisphere and the role of the right IPL in responding to salient environmental events.Here we critically appraise existing proposals regarding the functional architecture of the visual system, with special emphasis on the role of this region, particularly in the right hemisphere.We review evidence that shows the right IPL plays an important role in two different, but broadly complementary, aspects of attention: maintaining attentive control on current task goals as well as responding to salient new information or alerting stimuli in the environment.

View Article: PubMed Central - PubMed

Affiliation: UCL Institute of Cognitive Neuroscience, London, United Kingdom.

ABSTRACT
Current models of the visual pathways have difficulty incorporating the human inferior parietal lobe (IPL) into dorsal or ventral streams. Some recent proposals have attempted to integrate aspects of IPL function that were not hitherto dealt with well, such as differences between the left and right hemisphere and the role of the right IPL in responding to salient environmental events. However, we argue that these models also fail to capture adequately some important findings regarding the functions of the IPL. Here we critically appraise existing proposals regarding the functional architecture of the visual system, with special emphasis on the role of this region, particularly in the right hemisphere. We review evidence that shows the right IPL plays an important role in two different, but broadly complementary, aspects of attention: maintaining attentive control on current task goals as well as responding to salient new information or alerting stimuli in the environment. In our view, findings from functional imaging, electrophysiological and lesion studies are all consistent with the view that this region is part of a system that allows flexible reconfiguration of behaviour between these two alternative modes of operation. Damage to the right IPL leads to deficits in both maintaining attention and also responding to salient events, impairments that contribute to hemineglect, the classical syndrome that follows lesions of this region.

Show MeSH
Related in: MedlinePlus