@article{pmid40017733,

title = {Assessing cognitive flexibility in mice using a custom-built touchscreen chamber},

author = {Rui C Pais and Ali Goldani and Jayden Hutchison and Amirhossein Mazrouei and Mostafa Khavaninzadeh and Leonardo A Molina and Robert J Sutherland and Majid H Mohajerani},

doi = {10.3389/fnbeh.2025.1536458},

issn = {1662-5153},

year  = {2025},

date = {2025-01-01},

journal = {Front Behav Neurosci},

volume = {19},

pages = {1536458},

abstract = {Automated touchscreen systems have become increasingly prevalent in rodent model screening. This technology has significantly enhanced cognitive and behavioral assessments in mice and has bridged the translational gap between basic research using rodent models and human clinical research. Our study introduces a custom-built touchscreen operant conditioning chamber powered by a Raspberry Pi and a commercially available computer tablet, which effectively addresses the significant cost barriers traditionally associated with this technology. In order to test our prototype, we decided to train C57BL/6 mice on a visual discrimination serial-reversal task, and both C57BL/6 and Appstrain - an Alzheimer's Disease (AD) mouse model - on a new location discrimination serial-reversal task. The results demonstrated a clear progression toward asymptotic performance, particularly in the location discrimination task, which also revealed potential genotype-specific deficits, with App mice displaying an increase in the average number of errors in the first reversal as well as in perseverative errors, compared to wild-type mice. These results validate the practical utility of our touchscreen apparatus and underline its potential to provide insights into the behavioral and cognitive markers of neurobiological disorders.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid39364682,

title = {Psilocybin reduces functional correlation and the encoding of spatial information by neurons in mouse retrosplenial cortex},

author = {Victorita E Ivan and David P Tomàs-Cuesta and Ingrid M Esteves and Artur Luczak and Majid Mohajerani and Bruce L McNaughton and Aaron J Gruber},

doi = {10.1111/ejn.16558},

issn = {1460-9568},

year  = {2024},

date = {2024-11-01},

journal = {Eur J Neurosci},

volume = {60},

number = {10},

pages = {6395--6407},

abstract = {Psychedelic drugs have profound effects on perception, cognition and mood. How psychedelics affect neural signaling to produce these effects remains poorly understood. We investigated the effect of the classic psychedelic psilocybin on neural activity patterns and spatial encoding in the retrosplenial cortex of head-fixed mice navigating on a treadmill. The place specificity of neurons to distinct locations along the belt was reduced by psilocybin. Moreover, the stability of place-related activity across trials decreased. Psilocybin also reduced the functional correlation among simultaneously recorded neurons. The 5-HTR (serotonin 2A receptor) antagonist ketanserin blocked these effects. These data are consistent with proposals that psychedelics increase the entropy of neural signaling and provide a potential neural mechanism contributing to disorientation frequently reported by humans after taking psychedelics.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid39255789,

title = {Spatiotemporal resonance in mouse primary visual cortex},

author = {Rasa Gulbinaite and Mojtaba Nazari and Michael E Rule and Edgar J Bermudez-Contreras and Michael X Cohen and Majid H Mohajerani and J Alexander Heimel},

doi = {10.1016/j.cub.2024.07.091},

issn = {1879-0445},

year  = {2024},

date = {2024-09-01},

journal = {Curr Biol},

volume = {34},

number = {18},

pages = {4184--4196.e7},

abstract = {Human primary visual cortex (V1) responds more strongly, or resonates, when exposed to ∼10, ∼15-20, and ∼40-50 Hz rhythmic flickering light. Full-field flicker also evokes the perception of hallucinatory geometric patterns, which mathematical models explain as standing-wave formations emerging from periodic forcing at resonant frequencies of the simulated neural network. However, empirical evidence for such flicker-induced standing waves in the visual cortex was missing. We recorded cortical responses to flicker in awake mice using high-spatial-resolution widefield imaging in combination with high-temporal-resolution glutamate-sensing fluorescent reporter (iGluSnFR). The temporal frequency tuning curves in the mouse V1 were similar to those observed in humans, showing a banded structure with multiple resonance peaks (8, 15, and 33 Hz). Spatially, all flicker frequencies evoked responses in V1 corresponding to retinotopic stimulus location, but some evoked additional peaks. These flicker-induced cortical patterns displayed standing-wave characteristics and matched linear wave equation solutions in an area restricted to the visual cortex. Taken together, the interaction of periodic traveling waves with cortical area boundaries leads to spatiotemporal activity patterns that may affect perception.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38856286,

title = {Spatial-Temporal Analysis of Neural Desynchronization in Sleeplike States Reveals Critical Dynamics},

author = {Davor Curic and Surjeet Singh and Mojtaba Nazari and Majid H Mohajerani and Jörn Davidsen},

doi = {10.1103/PhysRevLett.132.218403},

issn = {1079-7114},

year  = {2024},

date = {2024-05-01},

journal = {Phys Rev Lett},

volume = {132},

number = {21},

pages = {218403},

abstract = {Sleep is characterized by nonrapid eye movement sleep, originating from widespread neuronal synchrony, and rapid eye movement sleep, with neuronal desynchronization akin to waking behavior. While these were thought to be global brain states, recent research suggests otherwise. Using time-frequency analysis of mesoscopic voltage-sensitive dye recordings of mice in a urethane-anesthetized model of sleep, we find transient neural desynchronization occurring heterogeneously across the cortex within a background of synchronized neural activity, in a manner reminiscent of a critical spreading process and indicative of an "edge-of-synchronization" phase transition.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38441248,

title = {A systematic review of altered resting-state networks in early deafness and implications for cochlear implantation outcomes},

author = {Zahra Jafari and Bryan E Kolb and Majid H Mohajerani},

doi = {10.1111/ejn.16295},

issn = {1460-9568},

year  = {2024},

date = {2024-05-01},

journal = {Eur J Neurosci},

volume = {59},

number = {10},

pages = {2596--2615},

abstract = {Auditory deprivation following congenital/pre-lingual deafness (C/PD) can drastically affect brain development and its functional organisation. This systematic review intends to extend current knowledge of the impact of C/PD and deafness duration on brain resting-state networks (RSNs), review changes in RSNs and spoken language outcomes post-cochlear implant (CI) and draw conclusions for future research. The systematic literature search followed the PRISMA guideline. Two independent reviewers searched four electronic databases using combined keywords: 'auditory deprivation', 'congenital/prelingual deafness', 'resting-state functional connectivity' (RSFC), 'resting-state fMRI' and 'cochlear implant'. Seventeen studies (16 cross-sectional and one longitudinal) met the inclusion criteria. Using the Crowe Critical Appraisal Tool, the publications' quality was rated between 65.0% and 92.5% (mean: 84.10%), ≥80% in 13 out of 17 studies. A few studies were deficient in sampling and/or ethical considerations. According to the findings, early auditory deprivation results in enhanced RSFC between the auditory network and brain networks involved in non-verbal communication, and high levels of spontaneous neural activity in the auditory cortex before CI are evidence of occupied auditory cortical areas with other sensory modalities (cross-modal plasticity) and sub-optimal CI outcomes. Overall, current evidence supports the idea that moreover intramodal and cross-modal plasticity, the entire brain adaptation following auditory deprivation contributes to spoken language development and compensatory behaviours.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38494417,

title = {Hippocampal ripples coincide with "up-state" and spindles in retrosplenial cortex},

author = {Rafael Pedrosa and Mojtaba Nazari and Loig Kergoat and Christophe Bernard and Majid Mohajerani and Federico Stella and Francesco Battaglia},

doi = {10.1093/cercor/bhae083},

issn = {1460-2199},

year  = {2024},

date = {2024-03-01},

journal = {Cereb Cortex},

volume = {34},

number = {3},

abstract = {During NREM sleep, hippocampal sharp-wave ripple (SWR) events are thought to stabilize memory traces for long-term storage in downstream neocortical structures. Within the neocortex, a set of distributed networks organized around retrosplenial cortex (RS-network) interact preferentially with the hippocampus purportedly to consolidate those traces. Transient bouts of slow oscillations and sleep spindles in this RS-network are often observed around SWRs, suggesting that these two activities are related and that their interplay possibly contributes to memory consolidation. To investigate how SWRs interact with the RS-network and spindles, we combined cortical wide-field voltage imaging, Electrocorticography, and hippocampal LFP recordings in anesthetized and sleeping mice. Here, we show that, during SWR, "up-states" and spindles reliably co-occur in a cortical subnetwork centered around the retrosplenial cortex. Furthermore, retrosplenial transient activations and spindles predict slow gamma oscillations in CA1 during SWRs. Together, our results suggest that retrosplenial-hippocampal interaction may be a critical pathway of information exchange between the cortex and hippocampus.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38298796,

title = {The Nonclassic Psychedelic Ibogaine Disrupts Cognitive Maps},

author = {Victorita E Ivan and David P Tomàs-Cuesta and Ingrid M Esteves and Davor Curic and Majid Mohajerani and Bruce L McNaughton and Joern Davidsen and Aaron J Gruber},

doi = {10.1016/j.bpsgos.2023.07.008},

issn = {2667-1743},

year  = {2024},

date = {2024-01-01},

journal = {Biol Psychiatry Glob Open Sci},

volume = {4},

number = {1},

pages = {275--283},

abstract = {BACKGROUND: The ability of psychedelic compounds to profoundly alter mental function has been long known, but the underlying changes in cellular-level information encoding remain poorly understood.nnMETHODS: We used two-photon microscopy to record from the retrosplenial cortex in head-fixed mice running on a treadmill before and after injection of the nonclassic psychedelic ibogaine (40 mg/kg intraperitoneally).nnRESULTS: We found that the cognitive map, formed by the representation of position encoded by ensembles of individual neurons in the retrosplenial cortex, was destabilized by ibogaine when mice had to infer position between tactile landmarks. This corresponded with increased neural activity rates, loss of correlation structure, and increased responses to cues. Ibogaine had surprisingly little effect on the size-frequency distribution of network activity events, suggesting that signal propagation within the retrosplenial cortex was largely unaffected.nnCONCLUSIONS: Taken together, these data support proposals that compounds with psychedelic properties disrupt representations that are important for constraining neocortical activity, thereby increasing the entropy of neural signaling. Furthermore, the loss of expected position encoding between landmarks recapitulated effects of hippocampal impairment, suggesting that disruption of cognitive maps or other hippocampal processing may be a contributing mechanism of discoordinated neocortical activity in psychedelic states.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37838246,

title = {Information-theory analysis of mouse string-pulling agrees with Fitts's Law: Increasing task difficulty engages multiple sensorimotor modalities in a dual oscillator behavior},

author = {Pardeepak S Sandhu and Behroo Mirza Agha and Samsoon Inayat and Surjeet Singh and Hardeep S Ryait and Majid H Mohajerani and Ian Q Whishaw},

doi = {10.1016/j.bbr.2023.114705},

issn = {1872-7549},

year  = {2024},

date = {2024-01-01},

journal = {Behav Brain Res},

volume = {456},

pages = {114705},

abstract = {Mouse string pulling, in which a mouse reels in a string with hand-over-hand movements, can provide insights into skilled motor behavior, neurological status, and cognitive function. The task involves two oscillatory movements connected by a string. The snout oscillates to track the pendulum movement of the string produced by hand-over-hand oscillations of pulling, and so the snout guides the hands to grasp the string. The present study examines the allocation of time required to pull strings of varying diameter. Movement is also described with end-point measures, string-pulling topography with 2D markerless pose estimates based on transfer learning with deep neural networks, and Mat-lab image-segmentation and heuristic algorithms for object tracking. With reduced string diameter, mice took longer to pull 60 cm long strings. They also made more pulling cycles, misses, and mouth engagements, and displayed changes in the amplitude and frequency of pull cycles. The time measures agree with Fitts's law in showing that increased task difficulty slows behavior and engages multiple compensatory sensorimotor modalities. The analysis reveals that time is a valuable resource in skilled motor behavior and information-theory can serve as a measure of its effective use.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37551444,

title = {Restoring neuronal chloride extrusion reverses cognitive decline linked to Alzheimer's disease mutations},

author = {Iason Keramidis and Brendan B McAllister and Julien Bourbonnais and Feng Wang and Dominique Isabel and Edris Rezaei and Romain Sansonetti and Phil Degagne and Justin P Hamel and Mojtaba Nazari and Samsoon Inayat and Jordan C Dudley and Annie Barbeau and Lionel Froux and Marie-Eve Paquet and Antoine G Godin and Majid H Mohajerani and Yves De Koninck},

doi = {10.1093/brain/awad250},

issn = {1460-2156},

year  = {2023},

date = {2023-12-01},

journal = {Brain},

volume = {146},

number = {12},

pages = {4903--4915},

abstract = {Disinhibition during early stages of Alzheimer's disease is postulated to cause network dysfunction and hyperexcitability leading to cognitive deficits. However, the underlying molecular mechanism remains unknown. Here we show that, in mouse lines carrying Alzheimer's disease-related mutations, a loss of neuronal membrane potassium-chloride cotransporter KCC2, responsible for maintaining the robustness of GABAA-mediated inhibition, occurs pre-symptomatically in the hippocampus and prefrontal cortex. KCC2 downregulation was inversely correlated with the age-dependent increase in amyloid-β 42 (Aβ42). Acute administration of Aβ42 caused a downregulation of membrane KCC2. Loss of KCC2 resulted in impaired chloride homeostasis. Preventing the decrease in KCC2 using long term treatment with CLP290 protected against deterioration of learning and cortical hyperactivity. In addition, restoring KCC2, using short term CLP290 treatment, following the transporter reduction effectively reversed spatial memory deficits and social dysfunction, linking chloride dysregulation with Alzheimer's disease-related cognitive decline. These results reveal KCC2 hypofunction as a viable target for treatment of Alzheimer's disease-related cognitive decline; they confirm target engagement, where the therapeutic intervention takes place, and its effectiveness.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid38012135,

title = {Cortical reactivation of spatial and non-spatial features coordinates with hippocampus to form a memory dialogue},

author = {HaoRan Chang and Ingrid M Esteves and Adam R Neumann and Majid H Mohajerani and Bruce L McNaughton},

doi = {10.1038/s41467-023-43254-7},

issn = {2041-1723},

year  = {2023},

date = {2023-11-01},

journal = {Nat Commun},

volume = {14},

number = {1},

pages = {7748},

abstract = {Episodic memories comprise diverse attributes of experience distributed across neocortical areas. The hippocampus is integral to rapidly binding these diffuse representations, as they occur, to be later reinstated. However, the nature of the information exchanged during this hippocampal-cortical dialogue remains poorly understood. A recent study has shown that the secondary motor cortex carries two types of representations: place cell-like activity, which were impaired by hippocampal lesions, and responses tied to visuo-tactile cues, which became more pronounced following hippocampal lesions. Using two-photon Ca imaging to record neuronal activities in the secondary motor cortex of male Thy1-GCaMP6s mice, we assessed the cortical retrieval of spatial and non-spatial attributes from previous explorations in a virtual environment. We show that, following navigation, spontaneous resting state reactivations convey varying degrees of spatial (trajectory sequences) and non-spatial (visuo-tactile attributes) information, while reactivations of non-spatial attributes tend to precede reactivations of spatial representations surrounding hippocampal sharp-wave ripples.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37950055,

title = {Repeated multi-domain cognitive training prevents cognitive decline, anxiety and amyloid pathology found in a mouse model of Alzheimer disease},

author = {Jogender Mehla and Scott H Deibel and Hadil Karem and Nancy S Hong and Shakhawat R Hossain and Sean G Lacoursiere and Robert J Sutherland and Majid H Mohajerani and Robert J McDonald},

doi = {10.1038/s42003-023-05506-6},

issn = {2399-3642},

year  = {2023},

date = {2023-11-01},

journal = {Commun Biol},

volume = {6},

number = {1},

pages = {1145},

abstract = {Education, occupation, and an active lifestyle, comprising enhanced social, physical, and mental components are associated with improved cognitive functions in aged people and may delay the progression of various neurodegenerative diseases including Alzheimer's disease. To investigate this protective effect, 3-month-old APP mice were exposed to repeated single- or multi-domain cognitive training. Cognitive training was given at the age of 3, 6, & 9 months. Single-domain cognitive training was limited to a spatial navigation task. Multi-domain cognitive training consisted of a spatial navigation task, object recognition, and fear conditioning. At the age of 12 months, behavioral tests were completed for all groups. Then, mice were sacrificed, and their brains were assessed for pathology. APP mice given multi-domain cognitive training compared to APP control group showed an improvement in cognitive functions, reductions in amyloid load and microgliosis, and a preservation of cholinergic function. Additionally, multi-domain cognitive training improved anxiety in APP mice as evidenced by measuring thigmotaxis behavior in the Morris water maze. There were mild reductions in microgliosis in the brain of APP mice with single-domain cognitive training. These findings provide causal evidence for the potential of certain forms of cognitive training to mitigate the cognitive deficits in Alzheimer disease.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37536439,

title = {Early tactile stimulation influences the development of Alzheimer's disease in gestationally stressed APP  adult offspring  mice},

author = {Shakhawat R Hossain and Hadil Karem and Zahra Jafari and Bryan E Kolb and Majid H Mohajerani},

doi = {10.1016/j.expneurol.2023.114498},

issn = {1090-2430},

year  = {2023},

date = {2023-10-01},

journal = {Exp Neurol},

volume = {368},

pages = {114498},

abstract = {Alzheimer's disease (AD) is associated with cerebral plaques and tangles, reduced synapse number, and shrinkage in several brain areas and these morphological effects are associated with the onset of compromised cognitive, motor, and anxiety-like behaviours. The appearance of both anatomical and behavioural symptoms is worsened by stress. The focus of this study was to examine the effect of neonatal tactile stimulation on AD-like behavioural and neurological symptoms on APP  mice, a mouse model of AD, who have been gestationally stressed. Our findings indicate that neonatal tactile stimulation improves cognition, motor skills, and anxiety-like symptoms in both gestationally stressed and non-stressed adult APP mice and that these alterations are associated with reduced Aβ plaque formation. Thus, tactile stimulation appears to be a promising non-invasive preventative strategy for slowing the onset of dementia in aging animals.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37531809,

title = {Weak-hyperactive hippocampal CA1 neurons in the prodromal stage of Alzheimer's disease in hybrid App × Thy1-GCaMP6s mice suggest disrupted plasticity},

author = {Samsoon Inayat and Brendan B McAllister and HaoRan Chang and Sean G Lacoursiere and Ian Q Whishaw and Robert J Sutherland and Majid H Mohajerani},

doi = {10.1016/j.neurobiolaging.2023.06.002},

issn = {1558-1497},

year  = {2023},

date = {2023-10-01},

journal = {Neurobiol Aging},

volume = {130},

pages = {154--171},

abstract = {This study investigated the impact of familial Alzheimer's disease (AD)-linked amyloid precursor protein (App) mutations on hippocampal CA1 neuronal activity and function at an early disease stage in App × Thy1-GCaMP6s (A-TG) mice using calcium imaging. Longitudinal assessment of spatial behavior at 12 and 18 months of age identified an early disease stage at 12 months when there was significant amyloid beta pathology with mild behavioral deficits. Hippocampal CA1 neuronal activity and event-related encoding of distance and time were therefore assessed at 12 months of age in several configurations of an air-induced running task to assess the dynamics of cellular activity. Neurons in A-TG mice displayed diminished (weaker) and more frequent (hyperactive) neuronal firing that was more pronounced during movement compared to immobility. Responsive neurons showed configuration-specific deficits in distance and time encoding with impairment in adapting their responses to changing configurations. These results suggest that at an early stage of AD in the absence of full-blown behavioral deficits, weak-hyperactive neuronal activity may induce impairments in sensory perception of changing environments.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37075972,

title = {Hearing loss and impaired short-term memory in an Alzheimer's disease mouse model of amyloid-beta pathology},

author = {Zahra Jafari and Navvab Afrashteh and Bryan E Kolb and Majid H Mohajerani},

doi = {10.1016/j.expneurol.2023.114413},

issn = {1090-2430},

year  = {2023},

date = {2023-07-01},

journal = {Exp Neurol},

volume = {365},

pages = {114413},

abstract = {Current evidence supports the link between hearing loss and Alzheimer's disease (AD). However, few studies report the hearing status of AD mice compared to wild-type mice. This study aimed to compare hearing thresholds and short-term memory (STM) performance of an AD (APP) mouse model of amyloid-beta (Aꞵ) pathology with C57BL/6 J and CBA/CaJ mice across age. The auditory brainstem response (ABR) test, using click and five tone-burst (TB) stimuli, was recorded at 2, 4, 6, 9, and 12 months. The novel object recognition (NOR) test, a measure of STM, was conducted at 6 and 12 months. While hearing thresholds were almost preserved in CBA/CaJ mice, they were not recorded at high frequencies with age in C57BL/6 J and AD mice, leading to island hearing (severe to profound hearing loss) at 9 and 12 months. AD mice showed increased hearing thresholds in TB8 and TB16 kHz at 6 and 9 months compared to C57BL/6 J mice. NOR findings were evidence of impaired STM in both C57BL/6 J and AD mice relative to CBA/CaJ mice, and a relationship was found between hearing thresholds and NOR measures in three groups. The findings were in support of the link between the degree of hearing loss and impaired STM.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37126447,

title = {Regional variation in cholinergic terminal activity determines the non-uniform occurrence of cortical slow waves during REM sleep in mice},

author = {Mojtaba Nazari and Javad Karimi Abadchi and Milad Naghizadeh and Edgar J Bermudez-Contreras and Bruce L McNaughton and Masami Tatsuno and Majid H Mohajerani},

doi = {10.1016/j.celrep.2023.112450},

issn = {2211-1247},

year  = {2023},

date = {2023-05-01},

journal = {Cell Rep},

volume = {42},

number = {5},

pages = {112450},

abstract = {Sleep consists of two basic stages: non-rapid eye movement (NREM) and rapid eye movement (REM) sleep. NREM sleep is characterized by slow high-amplitude cortical electroencephalogram (EEG) signals, while REM sleep is characterized by desynchronized cortical rhythms. Despite this, recent electrophysiological studies have suggested the presence of slow waves (SWs) in local cortical areas during REM sleep. Electrophysiological techniques, however, have been unable to resolve the regional structure of these activities because of relatively sparse sampling. Here, we map functional gradients in cortical activity during REM sleep using mesoscale imaging in mice and show local SW patterns occurring mainly in somatomotor and auditory cortical regions with minimum presence within the default mode network. The role of the cholinergic system in local desynchronization during REM sleep is also explored by calcium imaging of cholinergic activity within the cortex and analyzing structural data. We demonstrate weaker cholinergic projections and terminal activity in regions exhibiting frequent SWs during REM sleep.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid37096033,

title = {Hippocampal conjunctive and complementary CA1 populations relate sensory events to movement},

author = {Samsoon Inayat and Brendan B McAllister and Ian Q Whishaw and Majid H Mohajerani},

doi = {10.1016/j.isci.2023.106481},

issn = {2589-0042},

year  = {2023},

date = {2023-04-01},

journal = {iScience},

volume = {26},

number = {4},

pages = {106481},

abstract = {Hippocampal CA1 neurons respond to sensory stimuli during enforced immobility, movement, and their transitions in a new conveyor belt task. Head-fixed mice were exposed to light flashes or air streams while at rest, spontaneously moving, or running a fixed distance. Two-photon calcium imaging of CA1 neurons revealed that 62% of 3341 imaged cells were active during one or more of 20 sensorimotor events. Of these active cells, 17% were active for any given sensorimotor event, with a higher proportion during locomotion. The study found two types of cells: Conjunctive cells that were active across multiple events, and complementary cells that were active only during individual events, encoding novel sensorimotor events or their delayed repetitions. The configuration of these cells across changing sensorimotor events may signify the role of hippocampus in functional networks integrating sensory information with ongoing movement making it suitable for movement guidance.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid36255152,

title = {Tactile stimulation improves cognition, motor, and anxiety-like behaviors and attenuates the Alzheimer's disease pathology in adult APP mice},

author = {Shakhawat R Hossain and Hadil Karem and Zahra Jafari and Bryan E Kolb and Majid H Mohajerani},

doi = {10.1002/syn.22257},

issn = {1098-2396},

year  = {2023},

date = {2023-03-01},

journal = {Synapse},

volume = {77},

number = {2},

pages = {e22257},

abstract = {Alzheimer's disease (AD) is one of the largest health crises in the world. There are limited pharmaceutical interventions to treat AD, however, and most of the treatment options are not for cure or prevention, but rather to slow down the progression of the disease. The aim of this study was to examine the effect of tactile stimulation (TS) on AD-like symptoms and pathology in APP mice, a mouse model of AD. The results show that TS reduces the AD-like symptoms on tests of cognition, motor, and anxiety-like behaviors and these improvements in behavior are associated with reduced AD pathology in APP mice. Thus, TS appears to be a promising noninvasive strategy for slowing the onset of dementia in aging animals.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid35704850,

title = {Sensory experience selectively reorganizes the late component of evoked responses},

author = {Edgar Bermudez-Contreras and Andrea Gomez-Palacio Schjetnan and Artur Luczak and Majid H Mohajerani},

doi = {10.1093/cercor/bhac231},

issn = {1460-2199},

year  = {2023},

date = {2023-03-01},

journal = {Cereb Cortex},

volume = {33},

number = {6},

pages = {2626--2640},

abstract = {In response to sensory stimulation, the cortex exhibits an early transient response followed by late and slower activation. Recent studies suggest that the early component represents features of the stimulus while the late component is associated with stimulus perception. Although very informative, these studies only focus on the amplitude of the evoked responses to study its relationship with sensory perception. In this work, we expand upon the study of how patterns of evoked and spontaneous activity are modified by experience at the mesoscale level using voltage and extracellular glutamate transient recordings over widespread regions of mouse dorsal neocortex. We find that repeated tactile or auditory stimulation selectively modifies the spatiotemporal patterns of cortical activity, mainly of the late evoked response in anesthetized mice injected with amphetamine and also in awake mice. This modification lasted up to 60 min and results in an increase in the amplitude of the late response after repeated stimulation and in an increase in the similarity between the spatiotemporal patterns of the late early evoked response. This similarity increase occurs only for the evoked responses of the sensory modality that received the repeated stimulation. Thus, this selective long-lasting spatiotemporal modification of the cortical activity patterns might provide evidence that evoked responses are a cortex-wide phenomenon. This work opens new questions about how perception-related cortical activity changes with sensory experience across the cortex.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid36645126,

title = {Inhibition is a prevalent mode of activity in the neocortex around awake hippocampal ripples in mice},

author = {Javad Karimi Abadchi and Zahra Rezaei and Thomas Knöpfel and Bruce L McNaughton and Majid H Mohajerani},

doi = {10.7554/eLife.79513},

issn = {2050-084X},

year  = {2023},

date = {2023-01-01},

journal = {Elife},

volume = {12},

abstract = {Coordinated peri-ripple activity in the hippocampal-neocortical network is essential for mnemonic information processing in the brain. Hippocampal ripples likely serve different functions in sleep and awake states. Thus, the corresponding neocortical activity patterns may differ in important ways. We addressed this possibility by conducting voltage and glutamate wide-field imaging of the neocortex with concurrent hippocampal electrophysiology in awake mice. Contrary to our previously published sleep results, deactivation and activation were dominant in post-ripple neocortical voltage and glutamate activity, respectively, especially in the agranular retrosplenial cortex (aRSC). Additionally, the spiking activity of aRSC neurons, estimated by two-photon calcium imaging, revealed the existence of two subpopulations of excitatory neurons with opposite peri-ripple modulation patterns: one increases and the other decreases firing rate. These differences in peri-ripple spatiotemporal patterns of neocortical activity in sleep versus awake states might underlie the reported differences in the function of sleep versus awake ripples.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}