As Huntington’s disease (HD) progresses, there is a significant loss of neurons in the striatum in addition to a distinct thinning of the cerebral cortex. Despite an early presence of sensorimotor deficits in patients with HD, electrophysiological studies designed to assess the integrity of thalamocortical circuits are sparse. Using the R6/2 mouse model of HD, we provide evidence of reduced connectivity between thalamic cells and their targeted cortical regions. Whole-cell patch clamp recordings from ventral anterolateral nucleus (VAL; motor) and ventral posteromedial nucleus (VPM; somatosensory) thalamic neurons in ex vivo brain slices of R6/2 and wild-type (WT) mice revealed that cells in both thalamic nuclei of R6/2 mice exhibited significant differences in passive and active cell membrane properties (smaller cell membrane capacitances, faster decay time constants and increased input resistances) compared with WT cells. Although only cells in the VPM of symptomatic R6/2 mice had more depolarized resting...

Although visual object recognition is well studied and relatively well understood, much less is known about how shapes are recognized by touch and how such haptic stimuli might be compared with visual shapes. One might expect that the processes of visual and haptic object recognition engage similar brain structures given the advantages of avoiding redundant brain circuitry and indeed there is some evidence that this is the case. A potentially fruitful approach to understanding the differences in how shapes might be neurally represented is to find an algorithmic method of comparing shapes, which agrees with human behavior and determines whether that method differs between different modality conditions. If not, it would provide further evidence for a shared representation of shape. We recruited human participants to perform a one-back same–different visual and haptic shape comparison task both within (i.e., comparing two visual shapes or two haptic shapes) and across (i.e., comparing visual with haptic shape...

Women report greater cigarette cravings during the menstrual cycle phase with higher circulating levels of 17β-estradiol (E2), which is metabolized to estrone (E1). Both E2 and E1 bind to estrogen receptors (ERs), which have been highly studied in the breast, uterus, and ovary. Recent studies have found that ERs are also located on GABAergic medium spiny neurons (MSNs) within the nucleus accumbens core (NAcore). Glutamatergic plasticity in NAcore MSNs is altered following nicotine use; however, it is unknown whether estrogens impact this neurobiological consequence. To test the effect of estrogen on nicotine use, we ovariectomized (OVX) female rats that then underwent nicotine self-administration acquisition and compared them to ovary-intact (sham) rats. The OVX animals then received either sesame oil (vehicle), E2, or E1+E2 supplementation for 4 or 20 d before nicotine sessions. While both ovary-intact and OVX females readily discriminated levers, OVX females consumed less nicotine than sham females. Furt...

Inherited retinal degenerative diseases are a prominent cause of blindness. Although mutations causing death of photoreceptors are mostly known, the pathophysiology downstream in the inner retina and along the visual pathway is incompletely characterized in the earliest disease stages. Here, we investigated retinal, midbrain and cortical visual function using electroretinography (ERG), the optomotor response (OMR), visual evoked potentials (VEPs), respectively, and single unit electrophysiology at the primary visual cortex (V1) in light-adapted juvenile (approximately one-month-old) and young adult (three-month-old) Rho P23H/WT mice, representative of early-stage retinitis pigmentosa (RP). Photopic ERG revealed up to ∼30% hypersensitivity to light in Rho P23H/WT mice, as measured by the light intensity required to generate half-maximal b-wave (I50 parameter). Rho P23H/WT mice also showed increased OMRs toward low spatial frequency (SF) drifting gratings, indicative of visual overexcitation at the midbrain ...

In the article, “Perceptual Fading of a Stabilized Cortical Image: Replication in the Undergraduate Classroom,” by Nicole B. Massa, Jacob H. Deck, and Michael A. Grubb, which published …

Human multisensory grasping movements (i.e., seeing and feeling a handheld object while grasping it with the contralateral hand) are superior to movements guided by each separate modality. This multisensory advantage might be driven by the integration of vision with either the haptic position only or with both position and size cues. To contrast these two hypotheses, we manipulated visual uncertainty (central vs peripheral vision) and the availability of haptic cues during multisensory grasping. We showed a multisensory benefit regardless of the degree of visual uncertainty suggesting that the integration process involved in multisensory grasping can be flexibly modulated by the contribution of each modality. Increasing visual uncertainty revealed the role of the distinct haptic cues. The haptic position cue was sufficient to promote multisensory benefits evidenced by faster actions with smaller grip apertures, whereas the haptic size was fundamental in fine-tuning the grip aperture scaling. These results ...

Neuroscience is not just for neuroscientists. It is for everyone, but it is absent from our high schools. High schools have a huge investment in STEM but do not include neuroscience, although neuroscience is more interesting and relevant to a person’s daily life than most other sciences. However, neuroscience opportunities are increasing for teenagers outside the standard curriculum.

Neurosciences and digital technologies combine into the booming field of “neurotechnologies” (NT). Prospects for medical applications are very promising. If the GAFAM invest millions of dollars in NT, this is not only to develop brain-machine interfaces to overcome disabilities and mental pathologies. There are also commercial issues aimed at the public, via the exploitation of brain data for personal uses and for supervision of individual behaviors. The capacity of NT to “manipulate the brains” calls for vigilance in two particular areas: respect of mental autonomy and protection of brain data. A major issue is to assess whether existing laws on the protection of human rights are sufficient to protect mental privacy or whether new rights - NeuroRights- must be established specifically. The present era is characterized by major advances in neurosciences and in digital technologies. Both combine into a booming field of investigation called “neurotechnologies” (NTs) that result from research into brain path...

Alzheimer’s disease (AD) is characterized by progressive cognitive impairment associated with synaptic dysfunction and dendritic spine loss and the pathologic hallmarks of β-amyloid (Aβ) plaques and hyperphosphorylated tau tangles. 14-3-3 proteins are a highly conserved family of proteins whose functions include regulation of protein folding, neuronal architecture, and synaptic function. Additionally, 14-3-3s interact with both Aβ and tau, and reduced levels of 14-3-3s have been shown in the brains of AD patients and in AD mouse models. Here, we examine the neuroprotective potential of the 14-3-3θ isoform in AD models. We demonstrate that 14-3-3θ overexpression is protective and 14-3-3θ inhibition is detrimental against oligomeric Aβ-induced neuronal death in primary cortical cultures. Overexpression of 14-3-3θ using an adeno-associated viral (AAV) vector failed to improve performance on behavioral tests, improve Aβ pathology, or affect synaptic density in the J20 AD mouse model. Similarly, crossing a seco...

The dendrites of cortical pyramidal neurons receive synaptic inputs from different pathways that are organized according to their laminar target. This architectural scheme provides cortical neurons with a spatial mechanism to separate information, which may support neural flexibility required during learning. Here, we investigated layer-specific plasticity of sensory encoding following learning by recording from two different dendritic compartments, tuft and basal dendrites, of layer 2/3 (L2/3) pyramidal neurons in the auditory cortex of mice. Following auditory fear conditioning, auditory-evoked Ca2+ responses were enhanced in tuft, but not basal, dendrites leading to increased somatic action potential output. This is in direct contrast to the long held (and debated) hypothesis that, despite extensive dendritic arbors, neurons function as a simple one-compartment model. Two computational models of varying complexity based on the experimental data illustrated that this learning-related increase of auditory...