The Central Nervous System Organization of Behavior
Rolland S. Parker in Concussive Brain Trauma, 2016
Primary sensory cortex: Each of the sensory cortices have a unimodal sensory association area. To illustrate, we will consider the distribution of the optic nerve tract. The retinal axons proceed to the optic chiasma, where some fibers decussate to the opposite side. The major visual pathway for conscious vision is to the dorsal lateral geniculate nucleus of the thalamus, which projects to the striate cortex of the occipital lobe. Spatial information is related from the striate cortex to the posterior parietal cortex. Form and color information is relayed to the inferotemporal cortex, which is involved in complex functioning, including visual recognition of objects and individuals. Visual projections to the midbrain roof (superior colliculus) are involved with spatial projections of the visual world. Similar associated maps involving auditory and somatosensory space are projected into the deeper layers. Superior colliculus visual input is related to the pulvinar (dorsal thalamus) and then to the extrastriate visual cortical areas bordering the primary visual cortex of the occipital lobe (Butler, 2002) (see Figure 3.1, 3.2, and Figure 3.3).
Motor Areas in the Frontal Lobe: The Anatomical Substrate for the Central Control of Movement
Alexa Riehle, Eilon Vaadia in Motor Cortex in Voluntary Movements, 2004
In general, the density of projections from these "visual areas" in posterior parietal cortex increases as one proceeds from the caudal border of the PMd to the prePMd.146-149 Some have argued that these projections provide a neural substrate for the visual guidance of reaching movements to objects in extrapersonal space.146-149 It is unclear, however, whether the visual information provided by these regions is sufficient for the accurate localization of targets. For instance, area V6A has the most direct visual input to the motor areas in the frontal lobe. V6A neurons have large receptive fields located in the periphery of the visual field. Such fields seem better suited to alert the motor system and shift attention to a particular quadrant of space176-178 than to drive the visuomotor transformation required to reach out and grasp an object.
Disruptions in physical substrates of vision following traumatic brain injury
Mark J. Ashley, David A. Hovda in Traumatic Brain Injury, 2017
The selective attention network is a total cortical network involved in voluntary top-down processing. This network includes the association cortices and the posterior parietal lobes, dorsolateral frontal lobe, and the anterior cingulate cortex of the limbic system. The posterior parietal cortex mediates visual attentional function, the dorsolateral frontal lobe mediates motor and executive attentional function, and the anterior cingulate mediates motivational aspects of selective attention or salience. The major long association tract connecting the anterior and posterior association areas in selective attention is the superior longitudinal fasciculus. Each hemisphere directs the attentional focus to the contralateral hemispace, both personal and extrapersonal. The left posterior parietal lobe disengages from objects whereas the right posterior parietal lobe predominately disengages from location. Sustained attention is more under the control of the frontal areas, predominately the right hemisphere as well as the anterior corpus callosum.
Spatial neglect treatment: The brain’s spatial-motor Aiming systems
Published in Neuropsychological Rehabilitation, 2022
A. M. Barrett, Kelly M. Goedert, Alexandre R. Carter, Amit Chaudhari
Finally, a true understanding of directional motor biases will require that we are able to consider several neurophysiological fundamental sources of asymmetry. Posterior parietal cortex is (a) involved in motor planning and (b) may support improved movement after rehabilitation in patients with spatial neglect (Mattingley et al., 1998). We also need to measure electrophysiologic, hemodynamic, and cellular activation parameters to test, for example, whether loss of competitive equilibrium between hemispheres (Kinsbourne, 1977), altered gradients of information flow in local circuits (Nakayama et al., 2016), changes in preferred directional tuning at the level of individual neurons, or the disruption of cholinergic, adrenergic and dopaminergic neurotransmission (Luvizutto et al., 2015) may be more likely to account for symptoms. These method may be fruitful to co-integrate with lesion-symptom studies (Karnath et al., 2018), once large groups of well-characterized spatial neglect patients with Aiming spatial neglect are available. Thus, researchers studying spatial neglect rehabilitation should consider (1) dividing patients by presence or absence of frontal/striatal injury, or frontal brain disconnection (2) examining pre/post neurophysiologic parameters such as motor or sensory evoked potentials, brain activation, and brain vascular dynamics (Boukrina et al., 2019).
Cathodal tDCS of the Left Posterior Parietal Cortex Increases Proprioceptive Drift
Published in Journal of Motor Behavior, 2019
João Roberto Ventura de Oliveira, Marco Aurélio Romano-Silva, Herbert Ugrinowitsch, Tércio Apolinário-Souza, Lidiane Aparecida Fernandes, Juliana Otoni Parma, Guilherme Menezes Lage
Multimodal integration has well-known associations with several cortical areas (Roland, 1993). Among these areas, the posterior parietal cortex (PPC) stands out for its importance in the formation of sensory representations that are involved in both movement planning and error corrections (Andersen, Snyder, Bradley, & Xing, 1997; Culham et al., 2003; Desmurget et al., 1999; Lage et al., 2015; Mutha, Stapp, Sainburg, & Haaland, 2014; Ruschel et al., 2014). Transcranial magnetic stimulation (TMS) applied to the left PPC alters the quality of online corrections (Desmurget et al., 1999) and adjustments of motor commands necessary for adapting to new arm trajectories (Della-Maggiore, Malfait, Ostry, & Paus, 2004). The PPC is usually associated with the formation of proprioceptive drift, but interestingly, to our knowledge, there is no study investigating this association in aiming movements. Transcranial direct current stimulation (tDCS) applied to the PPC interferes in cognitive representations involving spatial memory (England, Fyock, Gillis, & Hampstead, 2015), visual short-term memory (Tseng et al., 2012), and working memory (Berryhill, Wencil, Coslett, & Olson, 2010). Thus, the use of cathodal tDCS on the left PPC may, among other effects, inhibit sensory representations of movement, increasing the magnitude and the rate of the proprioceptive drift in aiming movements without vision.
tDCS effects on task-related activation and working memory performance in traumatic brain injury: A within group randomized controlled trial
Published in Neuropsychological Rehabilitation, 2021
Jacqueline A. Rushby, Frances M. De Blasio, Jodie A. Logan, Travis Wearne, Emma Kornfeld, Emily Jane Wilson, Colleen Loo, Donel Martin, Skye McDonald
Finally, an important limitation has been the placement of the anode in TBI participants. This is commonly placed over the (typically left) dorsolateral prefrontal cortex (Kang et al., 2012; Lesniak et al., 2013; Sacco et al., 2016; Ulam et al., 2015) to improve working memory. However, the frontal lobes are extremely vulnerable to TBI. There is often significant atrophy and increased fluid that alters the conductive path of tDCS in idiosyncratic patterns that reflect individual neuropathology (Wagner et al., 2007). The posterior parietal cortex is also part of the neural network thought to mediate working memory, being activated during working memory tasks (Buchsbaum & D'Esposito, 2008; Olson & Berryhill, 2009; Wager & Smith, 2003). tDCS to the parietal cortex stimulates overlapping frontoparietal neural networks to frontal stimulation and yields equivalent enhancement of working memory (Jones, Stephens, et al., 2015). tDCS to right and left parietal regions has been demonstrated to improve visual working memory (Heimrath et al., 2012; Heinen et al., 2016; Jones, Stephens, et al., 2015; Jones & Berryhill, 2012; Tseng et al., 2012) and verbal learning (Jones, Gözenman, & Berryhill, 2014) respectively in healthy adults. The parietal lobes are less likely to be impacted by TBI (Bigler, 2007) and, therefore, the parietal region was chosen for the current study, with the anode on the left parietal lobe and the cathode placed on the homologous site on the contralateral hemisphere.
Related Knowledge Centers
- Apraxia
- Attention
- Dorsolateral Prefrontal Cortex
- Inferior Parietal Lobule
- Intraparietal Sulcus
- Parietal Lobe
- Postcentral Gyrus
- Superior Parietal Lobule
- Supramarginal Gyrus
- Hemispatial Neglect