Parietal Cortex Area Research Articles

EEG-Correlates of Competition and Cooperation

The aim was to investigate the peculiarities and localization of the current source density of α- and θ-frequency bands accompanying competition and cooperation with another player, as well as individual figure building in a computer game. The sample included forty-two volunteers (24 females) between the ages of 18 and 47. Analysis of differences in the current source density of 127 channel EEG under different game conditions was performed in the eLoreta program. During competition, the θ-current source density in the anterior cingulate cortex and medial prefrontal cortex was greater than during cooperation. According to the literature on functional correlates of θ-rhythm, it can be suggested that the greater increase in medial frontal θ-rhythm detected during competition may be related to focused attention and cognitive control processes. The alpha current source density in the parietal and visual cortex areas during interactive game modes (cooperation and competition) was lower compared to the individual mode. During cooperation the α-current source density was lower compared to the competition mode. The greatest decrease of the α-current source density in the cooperation mode is consistent with idea of a relation between α-rhythm decrease and the processes of understanding the other person’s intentions.

RTMS over the human medial parietal cortex impairs online reaching corrections

Indirect correlational evidence suggests that the posteromedial sector of the human parietal cortex (area hV6A) is involved in reaching corrections. We interfered with hV6A functions using repetitive transcranial magnetic stimulation (rTMS) while healthy participants performed reaching movements and in-flight adjustments of the hand trajectory in presence of unexpected target shifts. rTMS over hV6A specifically altered action reprogramming, causing deviations of the shifted trajectories, particularly along the vertical dimension (i.e., distance). This study provides evidence of the functional relevance of hV6A in action reprogramming while a sudden event requires a change in performance and shows that hV6A also plays a role in state estimation during reaching. These findings are in line with neurological data showing impairments in actions performed along the distance dimension when lesions occur in the dorsal posterior parietal cortex.

Reversible deactivation of motor cortex reveals that areas in parietal cortex are differentially dependent on motor cortex for the generation of movement.

Primates are characterized by specializations for manual manipulation, including expansion of posterior parietal cortex (PPC) and, in Catarrhines, evolution of a dexterous hand and opposable thumb. Previous studies examined functional interactions between motor cortex and PPC in New World monkeys and galagos, by inactivating M1 and evoking movements from PPC. These studies found that portions of PPC depend on M1 to generate movements. We now add a species that more closely resembles humans in hand morphology and PPC: macaques. Inactivating portions of M1 resulted in all evoked movements being reduced (28%) or completely abolished (72%) at the PPC sites tested (in areas 5L, PF, and PFG). Anterior parietal area 2 was similarly affected (26% reduced and 74% abolished) and area 1 was the least affected (12% no effect, 54% reduced, and 34% abolished). Unlike previous studies in New World monkeys and galagos, interactions between both nonanalogous (heterotopic) and analogous (homotopic) M1 and parietal movement domains were commonly found in most areas. These experiments demonstrate that there may be two parallel networks involved in motor control: a posterior parietal network dependent on M1 and a network that includes area 1 that is relatively independent of M1. Furthermore, it appears that the relative size and number of cortical fields in parietal cortex in different species correlates with homotopic and heterotopic effect prevalence. These functional differences in macaques could contribute to more numerous and varied muscle synergies across major muscle groups, supporting the expansion of the primate manual behavioral repertoire observed in Old World monkeys.NEW & NOTEWORTHY Motor cortex and anterior and posterior parietal cortex form a sensorimotor integration network. We tested the extent to which parietal areas could initiate movements independent of M1. Our findings support the contention that, although areas 2, 5L, PF, and PFG are highly dependent on M1 to produce movement, area 1 may constitute a parallel corticospinal pathway that can function somewhat independently of M1. A similar functional architecture may underlie dexterous tool use in humans.

Effects of Online Transcranial Alternating Current Stimulation Over the Parietal Cortex and Supplementary Motor Area on Bimanual Coordination in Elderly Women

Effects of Online Transcranial Alternating Current Stimulation Over the Parietal Cortex and Supplementary Motor Area on Bimanual Coordination in Elderly Women

Cerebral perfusion in post-stroke aphasia and its relationship to residual language abilities.

Stroke alters blood flow to the brain resulting in damaged tissue and cell death. Moreover, the disruption of cerebral blood flow (perfusion) can be observed in areas surrounding and distal to the lesion. These structurally preserved but suboptimally perfused regions may also affect recovery. Thus, to better understand aphasia recovery, the relationship between cerebral perfusion and language needs to be systematically examined. In the current study, we aimed to evaluate (i) how stroke affects perfusion outside of lesioned areas in chronic aphasia and (ii) how perfusion in specific cortical areas and perilesional tissue relates to language outcomes in aphasia. We analysed perfusion data from a large sample of participants with chronic aphasia due to left hemisphere stroke (n = 43) and age-matched healthy controls (n = 25). We used anatomically defined regions of interest that covered the frontal, parietal, and temporal areas of the perisylvian cortex in both hemispheres, areas typically known to support language, along with several control regions not implicated in language processing. For the aphasia group, we also looked at three regions of interest in the perilesional tissue. We compared perfusion levels between the two groups and investigated the relationship between perfusion levels and language subtest scores while controlling for demographic and lesion variables. First, we observed that perfusion levels outside the lesioned areas were significantly reduced in frontal and parietal regions in the left hemisphere in people with aphasia compared to the control group, while no differences were observed for the right hemisphere regions. Second, we found that perfusion in the left temporal lobe (and most strongly in the posterior part of both superior and middle temporal gyri) and inferior parietal areas (supramarginal gyrus) was significantly related to residual expressive and receptive language abilities. In contrast, perfusion in the frontal regions did not show such a relationship; no relationship with language was also observed for perfusion levels in control areas and all right hemisphere regions. Third, perilesional perfusion was only marginally related to language production abilities. Cumulatively, the current findings demonstrate that blood flow is reduced beyond the lesion site in chronic aphasia and that hypoperfused neural tissue in critical temporoparietal language areas has a negative impact on behavioural outcomes. These results, using perfusion imaging, underscore the critical and general role that left hemisphere posterior temporal regions play in various expressive and receptive language abilities. Overall, the study highlights the importance of exploring perfusion measures in stroke.

Brain neural synchronization mechanisms are affected by aging in cognitively unimpaired seniors and patients with Alzheimer’s disease and mild cognitive impairment

AbstractBackgroundThe resting state eyes‐closed electroencephalographic (rsEEG) alpha (8‐12 Hz) rhythms reflect cortical neural synchronization mechanisms underpinning the inhibition of sensory, cognitive, and motor areas in parietal, temporal, and occipital cortex during a condition of low vigilance. Here we tested the hypothesis that age may diversely affect rsEEG alpha (8‐12 Hz) rhythms recorded in normal elderly (Nold) seniors and patients with Alzheimer’s disease and mild cognitive impairment (ADMCI).MethodClinical, magnetic resonance imaging (MRI) and rsEEG datasets in 63 ADMCI and 60 Nold individuals were taken from an international archive. The rsEEG rhythms were investigated at individual delta, theta, and alpha frequency bands as well as fixed beta (14‐30 Hz) and gamma (30‐40 Hz) bands. Each group was stratified into three subgroups based on age ranges (i.e., tertiles).ResultAs compared to the younger Nold subgroups, the older one showed greater reductions in the rsEEG alpha rhythms with major topographical effects in posterior regions (Figure 1). On the contrary, in relation to the younger ADMCI subgroups, the older one displayed lesser reduction in those rhythms (Figure 1). Furthermore, a decrease in the total grey matter (GM) volume and total cortical thickness as well as an increase in the white matter (WM) hypointensity were found in the older ADMCI subgroups compared to the younger ADMCI subgroups (Figure 2).ConclusionThe results of the present study suggest that in Nold seniors, the aging factor may significantly affect neurophysiological brain neural synchronization mechanisms underpinning the generation of dominant rsEEG alpha rhythms. In contrast, rsEEG alpha rhythms in ADMCI patients may be more affected by the disease variants, with more deleterious effects observed in early‐ than the late‐onset ADMCI patients. In the ADMCI patients, the mere effects of the aging factor may be hidden by dysfunctions in subcortical structures, including the cholinergic basal forebrain and thalamus.

Spontaneous Behavioural Recovery Following Stroke Relates to the Integrity of Parietal and Temporal Regions.

Stroke is a devastating disease that results in neurological deficits and represents a leading cause of death and disability worldwide. Following a stroke, there is a degree of spontaneous recovery of function, the neural basis of which is of great interest among clinicians in their efforts to reduce disability following stroke and enhance rehabilitation. Conventionally, work on spontaneous recovery has tended to focus on the neural reorganization of motor cortical regions, with comparably little attention being paid to changes in non-motor regions and how these relate to recovery. Here we show, using structural neuroimaging in a macaque stroke model (N = 31) and by exploiting individual differences in spontaneous behavioural recovery, that the preservation of regions in the parietal and temporal cortices predict animal recovery. To characterize recovery, we performed a clustering analysis using Non-Human Primate Stroke Scale (NHPSS) scores and identified a good versus poor recovery group. By comparing the preservation of brain volumes in the two groups, we found that brain areas in integrity of brain areas in parietal, temporal and somatosensory cortex were associated with better recovery. In addition, a decoding approach performed across all subjects revealed that the preservation of specific brain regions in the parietal, somatosensory and medial frontal cortex predicted recovery. Together, these findings highlight the importance of parietal and temporal regions in spontaneous behavioural recovery.

New insights on single-neuron selectivity in the era of population-level approaches.

In the past, neuroscience was focused on individual neurons seen as the functional units of the nervous system, but this approach fell short over time to account for new experimental evidence, especially for what concerns associative and motor cortices. For this reason and thanks to great technological advances, a part of modern research has shifted the focus from the responses of single neurons to the activity of neural ensembles, now considered the real functional units of the system. However, on a microscale, individual neurons remain the computational components of these networks, thus the study of population dynamics cannot prescind from studying also individual neurons which represent their natural substrate. In this new framework, ideas such as the capability of single cells to encode a specific stimulus (neural selectivity) may become obsolete and need to be profoundly revised. One step in this direction was made by introducing the concept of “mixed selectivity,” the capacity of single cells to integrate multiple variables in a flexible way, allowing individual neurons to participate in different networks. In this review, we outline the most important features of mixed selectivity and we also present recent works demonstrating its presence in the associative areas of the posterior parietal cortex. Finally, in discussing these findings, we present some open questions that could be addressed by future studies.

Dissociation between Attention-Dependent and Spatially Specific Illusory Shape Responses within the Topographic Areas of the Posterior Parietal Cortex.

The human visual system consists of multiple topographic maps that extend from the early visual cortex (EVC) along the dorsal and ventral processing streams. Responses to illusory shapes within these maps have been demonstrated in the ventral stream areas, in particular the lateral occipital complex (LOC). Recently, the intraparietal sulcus (IPS) of the dorsal stream has been linked to the processing of illusory shapes defined by motion. It remains unclear whether the topographically organized parietal areas also respond to stationary illusory shapes, which would suggest their generic role in representing illusory content. In the current study we measured brain responses using fMRI while 30 human participants (12 male) observed flickering inducers around the fixation task. The inducers either formed an illusory diamond in the center, a triangle in the left or right hemifield, or were inverted such that no illusory figure was formed. We compared responses of parietal regions IPS0-IPS5 and SPL1 to each illusory figure with the nonillusory condition. To determine the role of attentional modulation on illusory shape responses we manipulated the difficulty of the fixation task. Our results show that all IPS areas responded to illusory shapes. The more posterior areas IPS0-IPS3 additionally displayed a preference toward contralateral shapes, while the more anterior areas IPS4 and IPS5 showed response attenuation with increased task difficulty. We suggest that the IPS can represent illusory content generated not only by moving, but also by stationary stimuli, and that there is a functional dissociation between attention-dependent anterior and spatially specific posterior topographic maps.SIGNIFICANCE STATEMENT The traditional view of the ventral visual pathway being solely responsible for representation of objects has recently been challenged by demonstrating illusory shape representation within the dorsal visual pathway with moving bistable stimuli. Our results provide evidence for the dorsal stream contribution to representing not only moving, but also stationary illusory shapes. Our results also show a functional subdivision along the topographic maps, with spatially specific shape responses in the more posterior, and attention-dependent responses in the more anterior areas. These findings have implications for our understanding of the relationship between attention and grouping in healthy individuals and neuropsychological patients. Furthermore, IPS areas should be considered in theoretical accounts and models of how subjective content is generated in the brain.

A functional magnetic resonance imaging examination of audiovisual observation of a point-light string quartet using intersubject correlation and physical feature analysis.

We use functional Magnetic Resonance Imaging (fMRI) to explore synchronized neural responses between observers of audiovisual presentation of a string quartet performance during free viewing. Audio presentation was accompanied by visual presentation of the string quartet as stick figures observed from a static viewpoint. Brain data from 18 musical novices were obtained during audiovisual presentation of a 116 s performance of the allegro of String Quartet, No. 14 in D minor by Schubert played by the ‘Quartetto di Cremona.’ These data were analyzed using intersubject correlation (ISC). Results showed extensive ISC in auditory and visual areas as well as parietal cortex, frontal cortex and subcortical areas including the medial geniculate and basal ganglia (putamen). These results from a single fixed viewpoint of multiple musicians are greater than previous reports of ISC from unstructured group activity but are broadly consistent with related research that used ISC to explore listening to music or watching solo dance. A feature analysis examining the relationship between brain activity and physical features of the auditory and visual signals yielded findings of a large proportion of activity related to auditory and visual processing, particularly in the superior temporal gyrus (STG) as well as midbrain areas. Motor areas were also involved, potentially as a result of watching motion from the stick figure display of musicians in the string quartet. These results reveal involvement of areas such as the putamen in processing complex musical performance and highlight the potential of using brief naturalistic stimuli to localize distinct brain areas and elucidate potential mechanisms underlying multisensory integration.

Anthropomorphic or non-anthropomorphic? Effects of biological sex in observation of actions in a digital human model and a gantry robot model.

Robots are ever more relevant for everyday life, such as healthcare or rehabilitation, as well as for modern industrial environment. One important issue in this context is the way we perceive robots and their actions. From our previous study, evidence exists that sex can affect the way people perceive certain robot's actions. In our fMRI study, we analyzed brain activations of female and male participants, while they observed anthropomorphic and robotic movements performed by a human or a robot model. While lying in the scanner, participants rated the perceived level of anthropomorphic and robotic likeness of movements in the two models. The observation of the human model and the anthropomorphic movements similarly activated the biological motion coding areas in posterior temporal and parietal areas. The observation of the robot model activated predominantly areas of the ventral stream, whereas the observation of robotic movements activated predominantly the primary and higher order motor areas. To note, this later activation originated mainly from female participants, whereas male participants activated, in both robot model and robotic movements contrasts, areas in the posterior parietal cortex. Accordingly, the general contrast of sex suggests that men tend to use the ventro-dorsal stream most plausibly to rely on available previous knowledge to analyze the movements, whereas female participants use the dorso-dorsal and the ventral streams to analyze online the differences between the movement types and between the different models. The study is a first step toward the understanding of sex differences in the processing of anthropomorphic and robotic movements.

Feasibility of fNIRS in Children with Developmental Coordination Disorder

IntroductionBalance deficits are heterogeneous among children with Developmental Coordination Disorder (DCD). Balance performance depends on different balance domains, each associated with specific underlying neurological systems. In DCD, any of these domains can be affected, but the control mechanisms are poorly understood. The mirror neuron system (MNS) seems to play a key-role in DCD-related deficits. To understand the role of MNS as a control mechanism underlying the balance deficits, simultaneous registration of cortical MNS activity while performing balance tasks is imperative. Therefore, a protocol for combining real-time registration of cortical MNS activity during functional balance tasks in children with DCD, CP and TD is introduced. Methods: Children with DCD, CP and TD (n=108) aged 5-10yr perform preselected tasks of the Kids-BESTest, representing specific balance domains (mixed design): leaning with eyes closed (stability limits/verticality), single-leg-stance, alternate stair touching (anticipatory balance), in-place response, compensatory stepping backward (reactive balance) and walking over obstacles (gait stability). Simultaneously, functional Near-Infrared Spectroscopy (fNIRS) monitors cortical activity involving the MNS: premotor, inferior and superior parietal cortex and supplementary motor area. An 8-8-optode bundle, making 22 channels, targets this region of interest. Outcome measures are: (de)oxygenated hemoglobin concentration changes per task per channel. Results: In this ongoing research, the protocol was already feasible in 19 children (7.52±1.19). Conclusion: Simultaneous registration of cortical MNS activity (fNIRS) and Kids-BESTest scores will help increase the understanding of the control mechanisms underlying the heterogeneous balance problems in DCD. Consequently, first steps are made to confirm whether DCD shows deviant or delayed development.DisclosureNo significant relationships.

Cerebral metabolic pattern associated with progressive parkinsonism in non-human primates reveals early cortical hypometabolism

Dopaminergic denervation in patients with Parkinson's disease is associated with changes in brain metabolism. Cerebral in-vivo mapping of glucose metabolism has been studied in severe stable parkinsonian monkeys, but data on brain metabolic changes in early stages of dopaminergic depletion of this model is lacking. Here, we report cerebral metabolic changes associated with progressive nigrostriatal lesion in the pre-symptomatic and symptomatic stages of the progressive 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) monkey model of Parkinson's Disease. Monkeys (Macaca fascicularis) received MPTP injections biweekly to induce progressive grades of dopamine depletion. Monkeys were sorted according to motor scale assessments in control, asymptomatic, recovered, mild, and severe parkinsonian groups. Dopaminergic depletion in the striatum and cerebral metabolic patterns across groups were studied in vivo by positron emission tomography (PET) using monoaminergic ([11C]-dihydrotetrabenazine; 11C-DTBZ) and metabolic (2-[18F]-fluoro-2-deoxy-d-glucose; 18F-FDG) radiotracers. 11C-DTBZ-PET analysis showed progressive decrease of binding potential values in the striatum of monkeys throughout MPTP administration and the development of parkinsonian signs. 18F-FDG analysis in asymptomatic and recovered animals showed significant hypometabolism in temporal and parietal areas of the cerebral cortex in association with moderate dopaminergic nigrostriatal depletion. Cortical hypometabolism extended to involve a larger area in mild parkinsonian monkeys, which also exhibited hypermetabolism in the globus pallidum pars interna and cerebellum. In severe parkinsonian monkeys, cortical hypometabolism extended further to lateral-frontal cortices and hypermetabolism also ensued in the thalamus and cerebellum. Unbiased histological quantification of neurons in Brodmann's area 7 in the parietal cortex did not reveal neuron loss in parkinsonian monkeys versus controls. Early dopaminergic nigrostriatal depletion is associated with cortical, mainly temporo-parietal hypometabolism unrelated to neuron loss. These findings, together with recent evidence from Parkinson's Disease patients, suggest that early cortical hypometabolism may be associated and driven by subcortical changes that need to be evaluated appropriately. Altogether, these findings could be relevant when potential disease modifying therapies become available.

Reproducing the effect of hippocampal network-targeted transcranial magnetic stimulation on episodic memory

Repetitive transcranial magnetic stimulation (rTMS) targeted to the hippocampal network via the inferior parietal cortex (HN-Stim) can strengthen hippocampal-cortical connectivity and improve episodic memory, offering a potential clinical intervention. However, acceptance of this technique has been tempered by the infrequent reproduction of findings in rTMS research on cognitive processes. We tested the reproducibility of the HN-Stim effect on episodic memory in our laboratory using different procedures from those previously published. We tested episodic memory in 29 participants before, one day, and one week after, three consecutive days of 20 Hz HN-Stim. Participants received stimulation targeted to either the area of inferior parietal cortex maximally connected to the left anterior hippocampus (HN-Stim; N = 14) or the vertex (control; N = 15), where we expected no effect. HN-Stim increased episodic memory performance one day, but not one week, after the last stimulation session. While failing to reproduce the lasting beneficial effect on memory found by others after five days of treatment, we found robust effects on behavior 24 h after treatment. HN-Stim is a safe and reliable means of enhancing episodic memory and may have potential for boosting learning and treating memory deficits.

Relationship between resting state alpha electroencephalographic rhythms and aging in cognitively unimpaired seniors and patients with mild cognitive impairment due to Alzheimer’s disease and amnestic mild cognitive impairment

AbstractBackgroundThe rsEEG alpha rhythms reflect cortical neural synchronization mechanisms underpinning the inhibition of sensory, cognitive, and motor areas in parietal, temporal, and occipital cortex during a condition of low vigilance. Here we tested the hypothesis that age may diversely affect rsEEG alpha (8‐12 Hz) rhythms recorded in normal elderly (Nold) seniors and patients with Alzheimer’s disease and mild cognitive impairment (ADMCI).MethodClinical and rsEEG datasets in 63 ADMCI and 60 Nold individuals ‐ matched as demography, education, and gender ‐ were taken from an international archive. The rsEEG rhythms were investigated at individual delta, theta, and alpha frequency bands as well as fixed beta (14‐30 Hz) and gamma (30‐40 Hz) bands. Each group was stratified into three subgroups based on age ranges (i.e., tertiles).ResultAs compared to the younger Nold subgroups, the older one showed greater reductions in the rsEEG alpha rhythms with major topographical effects in posterior regions (Figure 1 top). On the contrary, in relation to the younger ADMCI subgroups, the older one displayed lesser reduction in those rhythms (Figure 1 bottom). Notably, the ADMCI subgroups pointed to similar cerebrospinal fluid AD diagnostic biomarkers, gray and white matter brain lesions as revealed by neuroimaging, and clinical and neuropsychological scores.ConclusionThe present results suggest that age may represent a deranging factor for dominant rsEEG alpha rhythms in Nold seniors, while rsEEG alpha rhythms in ADMCI patients may be more affected by the disease variants related to earlier vs. later onset of the AD.

Angiocentric glioma: A case report and review of the literature

BackgroundAngiocentric glioma (AG) is a rare, low-grade glioma with slow growth. In 2007, AG was first classified as a solid tumor according to the WHO classification of the central nervous system (WHO class I). The outcome and prognosis of most of the cases are very good, but a few cases with tumor metastasis and disease progression, even death, have been reported. We report a case and systematically analyze previous literature to increase our understanding of the disease and determine the factors that may affect disease progression to make prognostic judgments. Case presentationA young male patient complained of a 3-year history of epilepsy. Anti-epileptic drug treatment was ineffective. An imaging examination revealed a lesion in the left parietal cortex area. Thus, the lesion was completely resected. The pathological diagnosis was angiocentric glioma. During a follow-up of two years, the patient had epilepsy relief controlled by sodium valproate and a disease-free period. ConclusionAG is an epilepsy-related low-grade glioma that heals after complete resection in most reported cases. However, few reported cases have had disease progression and death. This result may be due to the pathological complexity of the diseased tissue. In addition, AG is usually found to have an MYB–QKI rearrangement on genetic analysis. Due to the small number of reported cases and studies, our understanding and knowledge of this disease are still lacking. The potential malignant changes and prognostic factors need to be verified in more than clinical cases and basic research in the future.

P300 and delay-discounting in obsessive\u2013compulsive disorder

Previous research showed that dysfunctions of fronto-striatal neural networks are implicated in the pathophysiology of obsessive–compulsive disorder (OCD). Accordingly, patients with OCD showed altered performances during decision-making tasks. As P300, evoked by oddball paradigms, is suggested to be related to attentional and cognitive processes and generated in the medial temporal lobe and orbitofrontal and cingulate cortices, it is of special interest in OCD research. Therefore, this study aimed to investigate P300 in OCD and its associations with brain activity during decision-making: P300, evoked by an auditory oddball paradigm, was analysed in 19 OCD patients and 19 healthy controls regarding peak latency, amplitude and source density power in parietal cortex areas by sLORETA. Afterwards, using a fMRI paradigm, Blood–oxygen-level-dependent (BOLD) contrast imaging was conducted during a delay-discounting paradigm. We hypothesised differences between groups regarding P300 characteristics and associations with frontal activity during delay-discounting. The P300 did not differ between groups, however, the P300 latency over the P4 electrode correlated negatively with the NEO-FFI score openness to experience in patients with OCD. In healthy controls, P300 source density power correlated with activity in frontal regions when processing rewards, a finding which was absent in OCD patients. To conclude, associations of P300 with frontal brain activation during delay-discounting were found, suggesting a contribution of attentional or context updating processes. Since this association was absent in patients with OCD, the findings could be interpreted as being indeed related to dysfunctions of fronto-striatal neural networks in patients with OCD.

Neuroimaging Techniques in Advertising Research: Main Applications, Development, and Brain Regions and Processes

Despite the advancement in neuroimaging tools, studies about using neuroimaging tools to study the impact of advertising on brain regions and processes are scant and remain unclear in academic literature. In this article, we have followed a literature review methodology and a bibliometric analysis to select empirical and review papers that employed neuroimaging tools in advertising campaigns and to understand the global research trends in the neuromarketing domain. We extracted and analyzed sixty-three articles from the Web of Science database to answer our study questions. We found four common neuroimaging techniques employed in advertising research. We also found that the orbitofrontal cortex (OFC), the ventromedial prefrontal cortex, and the dorsolateral prefrontal cortex play a vital role in decision-making processes. The OFC is linked to positive valence, and the lateral OFC and left dorsal anterior insula related in negative valence. In addition, the thalamus and primary visual area associated with the bottom-up attention system, whereas the top-down attention system connected to the dorsolateral prefrontal cortex, parietal cortex, and primary visual areas. For memory, the hippocampus is responsible for generating and processing memories. We hope that this study provides valuable insights about the main brain regions and processes of interest for advertising.

Temporal dynamics of neural activity in macaque frontal cortex assessed with large-scale recordings

The cortical network controlling the arm and hand when grasping objects consists of several areas in parietal and frontal cortex. Recently, more anterior prefrontal areas have also been implicated in object grasping, but their exact role is currently unclear. To investigate the neuronal encoding of objects during grasping in these prefrontal regions and their relation with other cortical areas of the grasping network, we performed large-scale recordings (more than 2000 responsive sites) in frontal cortex of monkeys during a saccade-reach-grasp task. When an object appeared in peripheral vision, the first burst of activity emerged in prearcuate areas (the FEF and area 45B), followed by dorsal and ventral premotor cortex, and a buildup of activity in primary motor cortex. After the saccade, prearcuate activity remained elevated while primary motor and premotor activity rose in anticipation of the upcoming arm and hand movement. Remarkably, a large number of premotor and prearcuate sites responded when the object appeared in peripheral vision and remained active when the object came into foveal vision. Thus, prearcuate and premotor areas continuously encode object information when directing gaze and grasping objects.

Thyroid hormone deiodinases response in brain of spontaneausly hypertensive rats after hypotensive effects induced by mandibular extension.

The deiodinases activate or inactivate the thyroid hormones (TH) in virtually all tissues in both physiological and pathological conditions. The three deiodinases, DIO1, DIO2, and DIO3, have different catalytic functions and regulate TH tissue distribution. The aim of the present study was to evaluate the modulation of gene expression of the deiodinases and TH transporters and protein levels of DIO1 in parietal and frontal areas of cerebral cortex of spontaneously hypertensive rats (SHRs), after two successive mandibular extensions (ME). ME was performed on anesthetized rats by a dilatator appropriately designed and real-time PCR and western blotting techniques were employed for gene expression and protein level study. Mean blood pressure (MBP) significantly decreased in 2ME-treated rats when compared to sham-operated rats (p < 0.001) and this decrease lasted for the entire observation period. In gene expression analysis, in 2ME-treated rats we did not observe any significant variation of DIO1 and DIO3 with respect to the sham-operated rats. Differently, DIO2 gene expression significantly increased in frontal area of 2ME-treated rats, with respect to sham-operated rats (p < 0.01). Furthermore, in parietal area, protein levels of DIO1 in 2ME-treated rats were significantly higher than in sham-operated rats (p < 0.01). Moreover MCT8 and OATP1C1 both resulted significantly higher (p < 0.05 and p < 0.001) in sham frontal cortex. In summary, our data on SHRs, while confirming the hypotensive effect of two MEs, show that the treatment also solicits the three deiodinases production in the cerebral cortex.