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Journal of Neurosurgery Jan 2024Deep brain stimulation (DBS) is a rapidly growing surgical option for patients with drug-resistant epilepsy who are not candidates for resective/ablative surgery. Recent...
OBJECTIVE
Deep brain stimulation (DBS) is a rapidly growing surgical option for patients with drug-resistant epilepsy who are not candidates for resective/ablative surgery. Recent randomized controlled trials have demonstrated efficacy of DBS of the anterior nucleus of the thalamus (ANT), particularly in frontal or temporal epilepsy, whereas DBS of the centromedian (CM) nucleus appears to be most suitable in well-defined generalized epilepsy syndromes. At the authors' institution, DBS candidates who did not fit the populations represented in these trials were managed with DBS of multiple distinct targets, which included ANT, CM, and less-studied nuclei-i.e., mediodorsal nucleus, pulvinar, and subthalamic nucleus. The goal of this study was to present the authors' experience with these types of cases, and to motivate future investigations that can determine the long-term efficacy of multitarget DBS.
METHODS
This single-center retrospective study of adult patients with drug-resistant epilepsy who underwent multitarget DBS was performed to demonstrate the feasibility and safety of this approach, and to present seizure outcomes. Patients in this cohort had epilepsy with features that were difficult to treat with DBS of the ANT or CM nucleus alone, including multifocal/multilobar, diffuse-onset, and/or posterior-onset seizures; or both generalized and focal seizures.
RESULTS
Eight patients underwent DBS of 2-3 distinct thalamic/subthalamic nuclei. DBS was performed with 2 electrodes in each hemisphere. All leads in each patient were implanted with either frontal or parietal trajectories. There were no surgical complications. Among those with > 6 months of follow-up (n = 5; range 7-21 months), all patients were responders in terms of overall seizure frequency and/or convulsive seizure frequency (i.e., ≥ 50% reduction). Two patients had adverse stimulation effects, which resolved with further programming.
CONCLUSIONS
Multitarget DBS is a procedurally feasible and safe treatment strategy to maximize outcomes in patients with complex epilepsy. The authors highlight their approach to inform future studies that are sufficiently powered to assess its efficacy.
Topics: Adult; Humans; Deep Brain Stimulation; Retrospective Studies; Epilepsy; Drug Resistant Epilepsy; Seizures; Electrodes, Implanted
PubMed: 37486888
DOI: 10.3171/2023.5.JNS23982 -
Nature Oct 2022Distinguishing sensory stimuli caused by changes in the environment from those caused by an animal's own actions is a hallmark of sensory processing. Saccades are rapid...
Distinguishing sensory stimuli caused by changes in the environment from those caused by an animal's own actions is a hallmark of sensory processing. Saccades are rapid eye movements that shift the image on the retina. How visual systems differentiate motion of the image induced by saccades from actual motion in the environment is not fully understood. Here we discovered that in mouse primary visual cortex (V1) the two types of motion evoke distinct activity patterns. This is because, during saccades, V1 combines the visual input with a strong non-visual input arriving from the thalamic pulvinar nucleus. The non-visual input triggers responses that are specific to the direction of the saccade and the visual input triggers responses that are specific to the direction of the shift of the stimulus on the retina, yet the preferred directions of these two responses are uncorrelated. Thus, the pulvinar input ensures differential V1 responses to external and self-generated motion. Integration of external sensory information with information about body movement may be a general mechanism for sensory cortices to distinguish between self-generated and external stimuli.
Topics: Animals; Mice; Movement; Photic Stimulation; Retina; Saccades; Thalamic Nuclei; Visual Cortex
PubMed: 36104560
DOI: 10.1038/s41586-022-05196-w -
Advances in Anatomy, Embryology, and... 2018Pulvinar connectivity has been studied using a variety of neuroanatomical tracing techniques in both New and Old World monkeys. Connectivity studies have revealed...
Pulvinar connectivity has been studied using a variety of neuroanatomical tracing techniques in both New and Old World monkeys. Connectivity studies have revealed additional maps of the visual field other than those described using electrophysiological techniques, such as P3 in the capuchin monkey and P3/P4 in the macaque monkey. In this chapter, we argue that with increasing cortical size, the pulvinar developed new functional subdivisions in order to effectively interconnect and interact with the cortex.
Topics: Animals; Cebus; Pulvinar; Visual Cortex; Visual Fields; Visual Pathways
PubMed: 29116446
DOI: 10.1007/978-3-319-70046-5_5 -
Psychiatry Research. Neuroimaging Jun 2022Schizotypal personality disorder (SPD) resembles schizophrenia, but with attenuated brain abnormalities and the absence of psychosis. The thalamus is integral for...
Schizotypal personality disorder (SPD) resembles schizophrenia, but with attenuated brain abnormalities and the absence of psychosis. The thalamus is integral for processing and transmitting information across cortical regions and widely implicated in the neurobiology of schizophrenia. Comparing thalamic connectivity in SPD and schizophrenia could reveal an intermediate schizophrenia-spectrum phenotype to elucidate neurobiological risk and protective factors in psychosis. We used rsfMRI to investigate functional connectivity between the mediodorsal nucleus (MDN) and pulvinar, and their connectivity with frontal and temporal cortical regions, respectively in 43 healthy controls (HCs), and individuals in the schizophrenia-spectrum including 45 psychotropic drug-free individuals with SPD, and 20 individuals with schizophrenia-related disorders [(schizophrenia (n = 10), schizoaffective disorder (n = 8), schizophreniform disorder (n = 1) and psychosis NOS (n = 1)]. Individuals with SPD had greater functional connectivity between the MDN and pulvinar compared to individuals with schizophrenia. Thalamo-frontal (i.e., between the MDN and rostral middle frontal cortex) connectivity was comparable in SPD and HCs; in SPD greater connectivity was associated with less symptom severity. Individuals with schizophrenia had less thalamo-frontal connectivity and thalamo-temporal (i.e., pulvinar to the transverse temporal cortex) connectivity compared with HCs. Thalamo-frontal functional connectivity may be comparable in SPD and HCs, but abnormal in schizophrenia, and that this may be protective against psychosis in SPD.
Topics: Humans; Magnetic Resonance Imaging; Schizophrenia; Schizotypal Personality Disorder; Temporal Lobe; Thalamus
PubMed: 35240516
DOI: 10.1016/j.pscychresns.2022.111463 -
Brain and Nerve = Shinkei Kenkyu No... Dec 2015The basolateral limbic circuit (mediodorsal thalamic nucleus, anterior cingulated and prefrontal orbital cortex, anterior temporal cortex, and amygdala), the mediodorsal... (Review)
Review
The basolateral limbic circuit (mediodorsal thalamic nucleus, anterior cingulated and prefrontal orbital cortex, anterior temporal cortex, and amygdala), the mediodorsal thalamic nucleus circuit, and part of the frontal-subcortical circuits (anterior cingulate and prefrontal orbital cortex, caudate nucleus and nucleus accumbens, globus pallidus, and mediodorsal thalamic nucleus), and the anterior cingulate and prefrontal orbital cortex circuit are crucial systems for forming and expressing emotions. There are reciprocal projections between the hypothalamus, anterior cingulate cortex and prefrontal orbital cortex, and between the hypothalamus and the amygdale. Therefore, destruction of the mediodorsal thalamic nucleus and the hypothalamus can cause abnormal expression of emotions. Recently, converging evidence suggests that the pulvinar nucleus in the posterior thalamus mediates emotional visual information processing through the colliculo-pulvino-amygdalar pathway and/or through the colliculo-pulvino-cortical pathways. These pathways seem to contribute to the unconscious and/or conscious fast processing of ecologically relevant stimuli. Therefore, destruction of the pulvinar can cause impaired reaction to visual threats, such as photographs of a cockroach and fearfull facial expressions, if the stimuli are exposed briefly.
Topics: Aged; Amygdala; Emotions; Frontal Lobe; Humans; Limbic System; Male; Neural Pathways; Thalamus
PubMed: 26618764
DOI: 10.11477/mf.1416200328 -
Comprehensive Physiology Mar 2017Glutamatergic pathways in thalamus and cortex are divided into two distinct classes: driver, which carries the main information between cells, and modulator, which... (Review)
Review
Glutamatergic pathways in thalamus and cortex are divided into two distinct classes: driver, which carries the main information between cells, and modulator, which modifies how driver inputs function. Identifying driver inputs helps to reveal functional computational circuits, and one set of such circuits identified by this approach are cortico-thalamo-cortical (or transthalamic corticocortical) circuits. This, in turn, leads to the conclusion that there are two types of thalamic relay: first order nuclei (such as the lateral geniculate nucleus) that relay driver input from a subcortical source (i.e., retina), and higher order nuclei (such as the pulvinar) which are involved in these transthalamic pathways by relaying driver input from layer 5 of one cortical area to another. This thalamic division is also seen in other sensory pathways and beyond these so that most of thalamus by volume consists of higher-order relays. Many, and perhaps all, direct driver connections between cortical areas are paralleled by an indirect cortico-thalamo-cortical (transthalamic) driver route involving higher order thalamic relays. Such thalamic relays represent a heretofore unappreciated role in cortical functioning, and this assessment challenges and extends conventional views regarding both the role of thalamus and mechanisms of corticocortical communication. Finally, many and perhaps the vast majority of driver inputs relayed through thalamus arrive via branching axons, with extrathalamic targets often being subcortical motor centers. This raises the possibility that inputs relayed by thalamus to cortex also serve as efference copies, and this may represent an important feature of information relayed up the cortical hierarchy via transthalamic circuits. © 2017 American Physiological Society. Compr Physiol 7:713-739, 2017.
Topics: Animals; Basal Ganglia; Cerebral Cortex; Geniculate Bodies; Humans; Neural Pathways; Neurotransmitter Agents; Schizophrenia; Thalamus
PubMed: 28333385
DOI: 10.1002/cphy.c160032 -
Vision (Basel, Switzerland) Dec 2019Current evidence supports the view that the visual pulvinar of primates consists of at least five nuclei, with two large nuclei, lateral pulvinar ventrolateral (PLvl)... (Review)
Review
Current evidence supports the view that the visual pulvinar of primates consists of at least five nuclei, with two large nuclei, lateral pulvinar ventrolateral (PLvl) and central lateral nucleus of the inferior pulvinar (PIcl), contributing mainly to the ventral stream of cortical processing for perception, and three smaller nuclei, posterior nucleus of the inferior pulvinar (PIp), medial nucleus of the inferior pulvinar (PIm), and central medial nucleus of the inferior pulvinar (PIcm), projecting to dorsal stream visual areas for visually directed actions. In primates, both cortical streams are highly dependent on visual information distributed from primary visual cortex (V1). This area is so vital to vision that patients with V1 lesions are considered "cortically blind". When the V1 inputs to dorsal stream area middle temporal visual area (MT) are absent, other dorsal stream areas receive visual information relayed from the superior colliculus via PIp and PIcm, thereby preserving some dorsal stream functions, a phenomenon called "blind sight". Non-primate mammals do not have a dorsal stream area MT with V1 inputs, but superior colliculus inputs to temporal cortex can be more significant and more visual functions are preserved when V1 input is disrupted. The current review will discuss how the different visual streams, especially the dorsal stream, have changed during primate evolution and we propose which features are retained from the common ancestor of primates and their close relatives.
PubMed: 31905909
DOI: 10.3390/vision4010003 -
Journal of Clinical Neuroscience :... May 2022To compare the area of exposure to the cisternal thalamus associated with four surgical techniques: supracerebellar-infratentorial (SCIT), occipital interhemispheric...
OBJECTIVE
To compare the area of exposure to the cisternal thalamus associated with four surgical techniques: supracerebellar-infratentorial (SCIT), occipital interhemispheric (OI), transchoroidal (TC) and subtemporal before and after parahippocampal resection (ST and STh, respectively).
METHODS
All approaches were performed on both sides of three heads. Qualitative anatomical analyses were performed to understand anatomical limits, advantages, and flaws of each technique. Quantitative analyses for multiple repeated dependent variables assessed significant differences between areas of exposure.
RESULTS
Exposure area was significantly more extensive using TC and STh approaches compared to ST, OI, and SCIT. STh achieved a significantly wider exposure compared to ST. Regarding dissection angle, surrounding structures and limitations, ST approaches do not provide adequate exposure, nor alignment with the thalamic axis. The OI and STh may provide a better field of exposure, but without adequate alignment and challenging deeper dissections. TC provides better exposure of the cisternal pulvinar with access to lateral pulvinar at the atrium's anterior wall but is a transcortical route that disrupts non-pathological tissue. SCIT provides an adequate area of exposure with the possibility of alignment with the thalamus axis, thus allowing an easier dissection of deeper lesions.
CONCLUSIONS
For lesions at the pulvinar surface, OI and STh are adequate. For lesions restricted to medial pulvinar and deep along the thalamus axis, SCIT approaches are recommended. Lesions extending to the lateral pulvinar and ventricular atrium are best removed through TC approaches. The ST approach was not suitable to the cisternal pulvinar due to its limited angular exposure.
Topics: Cadaver; Humans; Microsurgery; Neurosurgical Procedures; Pulvinar; Thalamus
PubMed: 35298942
DOI: 10.1016/j.jocn.2022.03.016 -
The Journal of Neuroscience : the... Feb 2023Distributed cortical regions show differential responses to visual objects belonging to different domains varying by animacy (e.g., animals vs tools), yet it remains...
Distributed cortical regions show differential responses to visual objects belonging to different domains varying by animacy (e.g., animals vs tools), yet it remains unclear whether this is an organization principle also applying to the subcortical structures. Combining multiple fMRI activation experiments (two main experiments and six validation datasets; 12 females and 9 males in the main Experiment 1; 10 females and 10 males in the main Experiment 2), resting-state functional connectivity, and task-based dynamic causal modeling analysis in human subjects, we found that visual processing of images of animals and tools elicited different patterns of response in the pulvinar, with robust left lateralization for tools, and distinct, bilateral (with rightward tendency) clusters for animals. Such domain-preferring activity distribution in the pulvinar was associated with the magnitude with which the voxels were intrinsically connected with the corresponding domain-preferring regions in the cortex. The pulvinar-to-right-amygdala path showed a one-way shortcut supporting the perception of animals, and the modulation connection from pulvinar to parietal showed an advantage to the perception of tools. These results incorporate the subcortical regions into the object processing network and highlight that domain organization appears to be an overarching principle across various processing stages in the brain. Viewing objects belonging to different domains elicited different cortical regions, but whether the domain organization applied to the subcortical structures (e.g., pulvinar) was unknown. Multiple fMRI activation experiments revealed that object pictures belonging to different domains elicited differential patterns of response in the pulvinar, with robust left lateralization for tool pictures, and distinct, bilateral (with rightward tendency) clusters for animals. Combining the resting-state functional connectivity and dynamic causal modeling analysis on task-based fMRI data, we found domain-preferring activity distribution in the pulvinar aligned with that in cortical regions. These results highlight the need for coherent visual theories that explain the mechanisms underlying the domain organization across various processing stages.
Topics: Male; Female; Animals; Humans; Pulvinar; Magnetic Resonance Imaging; Brain; Brain Mapping; Amygdala
PubMed: 36596697
DOI: 10.1523/JNEUROSCI.0613-22.2022