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Articles 61 - 88 of 88
Full-Text Articles in Neuroscience and Neurobiology
Imaging Prior Information In The Brain, Scott Gorlin, Ming Meng, Jitendra Sharma, Hiroki Sugihara
Imaging Prior Information In The Brain, Scott Gorlin, Ming Meng, Jitendra Sharma, Hiroki Sugihara
Dartmouth Scholarship
In making sense of the visual world, the brain's processing is driven by two factors: the physical information provided by the eyes (“bottom-up” data) and the expectancies driven by past experience (“top-down” influences). We use degraded stimuli to tease apart the effects of bottom-up and top-down processes because they are easier to recognize with prior knowledge of undegraded images. Using machine learning algorithms, we quantify the amount of information that brain regions contain about stimuli as the subject learns the coherent images. Our results show that several distinct regions, including high-level visual areas and the retinotopic cortex, contain more information …
The Neurobiology Of Decision-Making And Responsibility: Reconciling Mechanism And Mindedness, Michael N. Shadlen, Adina L. Roskies
The Neurobiology Of Decision-Making And Responsibility: Reconciling Mechanism And Mindedness, Michael N. Shadlen, Adina L. Roskies
Dartmouth Scholarship
This essay reviews recent developments in neurobiology which are beginning to expose the mechanisms that underlie some elements of decision-making that bear on attributions of responsibility. These “elements” have been mainly studied in simple perceptual decision tasks, which are performed similarly by humans and non-human primates. Here we consider the role of neural noise, and suggest that thinking about the role of noise can shift the focus of discussions of randomness in decision-making away from its role in enabling alternate possibilities and toward a potential grounding role for responsibility.
Electrical Advantages Of Dendritic Spines, Allan T. Gulledge, Nicholas T. Carnevale, Greg J. Stuart
Electrical Advantages Of Dendritic Spines, Allan T. Gulledge, Nicholas T. Carnevale, Greg J. Stuart
Dartmouth Scholarship
Many neurons receive excitatory glutamatergic input almost exclusively onto dendritic spines. In the absence of spines, the amplitudes and kinetics of excitatory postsynaptic potentials (EPSPs) at the site of synaptic input are highly variable and depend on dendritic location. We hypothesized that dendritic spines standardize the local geometry at the site of synaptic input, thereby reducing location-dependent variability of local EPSP properties. We tested this hypothesis using computational models of simplified and morphologically realistic spiny neurons that allow direct comparison of EPSPs generated on spine heads with EPSPs generated on dendritic shafts at the same dendritic locations. In all morphologies …
Data Sharing In Neuroimaging Research, Jean-Baptiste Poline, Janis L. Breeze, Satrajit Ghosh, Krzysztof Gorgolewski, Yaroslav O. Halchenko
Data Sharing In Neuroimaging Research, Jean-Baptiste Poline, Janis L. Breeze, Satrajit Ghosh, Krzysztof Gorgolewski, Yaroslav O. Halchenko
Dartmouth Scholarship
Significant resources around the world have been invested in neuroimaging studies of brain function and disease. Easier access to this large body of work should have profound impact on research in cognitive neuroscience and psychiatry, leading to advances in the diagnosis and treatment of psychiatric and neurological disease. A trend toward increased sharing of neuroimaging data has emerged in recent years. Nevertheless, a number of barriers continue to impede momentum. Many researchers and institutions remain uncertain about how to share data or lack the tools and expertise to participate in data sharing. The use of electronic data capture (EDC) methods …
Selective Serotonergic Excitation Of Callosal Projection Neurons, Daniel Avesar, Allan T. Gulledge
Selective Serotonergic Excitation Of Callosal Projection Neurons, Daniel Avesar, Allan T. Gulledge
Dartmouth Scholarship
Serotonin (5-HT) acting as a neurotransmitter in the cerebral cortex is critical for cognitive function, yet how 5-HT regulates information processing in cortical circuits is not well understood. We tested the serotonergic responsiveness of layer 5 pyramidal neurons (L5PNs) in the mouse medial prefrontal cortex (mPFC), and found three distinct response types: long-lasting 5-HT1A (1A) receptor-dependent inhibitory responses (84% of L5PNs), 5-HT2A (2A) receptor-dependent excitatory responses (9%), and biphasic responses in which 2A-dependent excitation followed brief inhibition (5%). Relative to 5-HT-inhibited neurons, those excited by 5-HT had physiological properties characteristic of callosal/commissural (COM) neurons that project to the …
Vestibular And Attractor Network Basis Of The Head Direction Cell Signal In Subcortical Circuits, Benjamin J. Clark, Jeffrey S. Taube
Vestibular And Attractor Network Basis Of The Head Direction Cell Signal In Subcortical Circuits, Benjamin J. Clark, Jeffrey S. Taube
Dartmouth Scholarship
Accurate navigation depends on a network of neural systems that encode the moment-to-moment changes in an animal's directional orientation and location in space. Within this navigation system are head direction (HD) cells, which fire persistently when an animal's head is pointed in a particular direction (Sharp et al., 2001a; Taube, 2007). HD cells are widely thought to underlie an animal's sense of spatial orientation, and research over the last 25+ years has revealed that this robust spatial signal is widely distributed across subcortical and cortical limbic areas. The purpose of the present review is to summarize some of …
Derivation Of A Novel Efficient Supervised Learning Algorithm From Cortical-Subcortical Loops, Ashok Chandrashekar, Richard Granger
Derivation Of A Novel Efficient Supervised Learning Algorithm From Cortical-Subcortical Loops, Ashok Chandrashekar, Richard Granger
Dartmouth Scholarship
Although brain circuits presumably carry out powerful perceptual algorithms, few instances of derived biological methods have been found to compete favorably against algorithms that have been engineered for specific applications. We forward a novel analysis of a subset of functions of cortical-subcortical loops, which constitute more than 80% of the human brain, thus likely underlying a broad range of cognitive functions. We describe a family of operations performed by the derived method, including a non-standard method for supervised classification, which may underlie some forms of cortically dependent associative learning. The novel supervised classifier is compared against widely used algorithms for …
Domain Architecture Of A Calcium-Permeable Ampa Receptor In A Ligand-Free Conformation, Charles R. Midgett, Avinash Gill, Dean R. Madden
Domain Architecture Of A Calcium-Permeable Ampa Receptor In A Ligand-Free Conformation, Charles R. Midgett, Avinash Gill, Dean R. Madden
Dartmouth Scholarship
Ligand-gated ion channels couple the free energy of agonist binding to the gating of selective transmembrane ion pores, permitting cells to regulate ion flux in response to external chemical stimuli. However, the stereochemical mechanisms responsible for this coupling remain obscure. In the case of the ionotropic glutamate receptors (iGluRs), the modular nature of receptor subunits has facilitated structural analysis of the N-terminal domain (NTD), and of multiple conformations of the ligand-binding domain (LBD). Recently, the crystallographic structure of an antagonist-bound form of the receptor was determined. However, disulfide trapping of this conformation blocks channel opening, suggesting that channel activation involves …
Aging Is Associated With Positive Responding To Neutral Information But Reduced Recovery From Negative Information, Carien M. Van Reekum, Stacey M. Schaefer, Regina C. Lapate, Catherine J. Norris, Lawrence L. Greischar, Richard J. Davidson
Aging Is Associated With Positive Responding To Neutral Information But Reduced Recovery From Negative Information, Carien M. Van Reekum, Stacey M. Schaefer, Regina C. Lapate, Catherine J. Norris, Lawrence L. Greischar, Richard J. Davidson
Dartmouth Scholarship
Studies on aging and emotion suggest an increase in reported positive affect, a processing bias of positive over negative information, as well as increasingly adaptive regulation in response to negative events with advancing age. These findings imply that older individuals evaluate information differently, resulting in lowered reactivity to, and/or faster recovery from, negative information, while maintaining more positive responding to positive information. We examined this hypothesis in an ongoing study on Midlife in the US (MIDUS II) where emotional reactivity and recovery were assessed in a large number of respondents (N = 159) from a wide age range (36–84 …
Mind Perception: Real But Not Artificial Faces Sustain Neural Activity Beyond The N170/Vpp, Thalia Wheatley, Anna Weinberg, Christine Looser, Tim Moran, Greg Hajcak
Mind Perception: Real But Not Artificial Faces Sustain Neural Activity Beyond The N170/Vpp, Thalia Wheatley, Anna Weinberg, Christine Looser, Tim Moran, Greg Hajcak
Dartmouth Scholarship
Faces are visual objects that hold special significance as the icons of other minds. Previous researchers using event-related potentials (ERPs) have found that faces are uniquely associated with an increased N170/vertex positive potential (VPP) and a more sustained frontal positivity. Here, we examined the processing of faces as objects vs. faces as cues to minds by contrasting images of faces possessing minds (human faces), faces lacking minds (doll faces), and non-face objects (i.e., clocks). Although both doll and human faces were associated with an increased N170/VPP from 175–200 ms following stimulus onset, only human faces were associated with a sustained …
Differential Activation Of Frontoparietal Attention Networks By Social And Symbolic Spatial Cues, Andrew D. Engell, Lauri Nummenmaa, Nikolaas N. Oosterhof, Richard N. Henson, James V. Haxby, Andrew J. Calder
Differential Activation Of Frontoparietal Attention Networks By Social And Symbolic Spatial Cues, Andrew D. Engell, Lauri Nummenmaa, Nikolaas N. Oosterhof, Richard N. Henson, James V. Haxby, Andrew J. Calder
Dartmouth Scholarship
Perception of both gaze-direction and symbolic directional cues (e.g. arrows) orient an observer’s attention toward the indicated location. It is unclear, however, whether these similar behavioral effects are examples of the same attentional phenomenon and, therefore, subserved by the same neural substrate. It has been proposed that gaze, given its evolutionary significance, constitutes a ‘special’ category of spatial cue. As such, it is predicted that the neural systems supporting spatial reorienting will be different for gaze than for non-biological symbols. We tested this prediction using functional magnetic resonance imaging to measure the brain’s response during target localization in which laterally …
Behind The Mask: The Influence Of Mask-Type On Amygdala Response To Fearful Faces, M Justin Kim, Rebecca A. Loucks, Maital Neta, F. Caroline Davis, Jonathan A. Oler, Emily C. Mazzulla, Paul J. Whalen
Behind The Mask: The Influence Of Mask-Type On Amygdala Response To Fearful Faces, M Justin Kim, Rebecca A. Loucks, Maital Neta, F. Caroline Davis, Jonathan A. Oler, Emily C. Mazzulla, Paul J. Whalen
Dartmouth Scholarship
In this study, we compared the effects of using neutral face masks vs non-face pattern masks on amygdala activity to masked fearful faces. Twenty-seven subjects viewed 18 s blocks of either fearful or happy faces masked with either neutral faces or patterns, while their brain activity was measured using functional magnetic resonance imaging. Results replicated increased amygdala activation to face-masked fearful vs happy faces. In the pattern mask condition, the amygdala discriminated between masked fearful and happy faces, but this effect manifested as a decrease in activation to fearful faces compared to happy faces. This interactive effect between facial expression …
Effects Of Socioeconomic Status On Brain Development, And How Cognitive Neuroscience May Contribute To Levelling The Playing Field, Rajeev Raizada, Mark M. Kishiyama
Effects Of Socioeconomic Status On Brain Development, And How Cognitive Neuroscience May Contribute To Levelling The Playing Field, Rajeev Raizada, Mark M. Kishiyama
Dartmouth Scholarship
The study of socioeconomic status (SES) and the brain finds itself in a circumstance unusual for Cognitive Neuroscience: large numbers of questions with both practical and scientific importance exist, but they are currently under-researched and ripe for investigation. This review aims to highlight these questions, to outline their potential significance, and to suggest routes by which they might be approached. Although remarkably few neural studies have been carried out so far, there exists a large literature of previous behavioural work. This behavioural research provides an invaluable guide for future neuroimaging work, but also poses an important challenge for it: how …
The Principled Control Of False Positives In Neuroimaging, Craig M. Bennett, George L. Wolford, Michael B. Miller
The Principled Control Of False Positives In Neuroimaging, Craig M. Bennett, George L. Wolford, Michael B. Miller
Dartmouth Scholarship
An incredible amount of data is generated in the course of a functional neuroimaging experiment. The quantity of data gives us improved temporal and spatial resolution with which to evaluate our results. It also creates a staggering multiple testing problem. A number of methods have been created that address the multiple testing problem in neuroimaging in a principled fashion. These methods place limits on either the familywise error rate (FWER) or the false discovery rate (FDR) of the results. These principled approaches are well established in the literature and are known to properly limit the amount of false positives across …
A Functional Role For The Ventrolateral Prefrontal Cortex In Non-Spatial Auditory Cognition, Y. E. Cohen, B. E. Russ, S. J. Davis, A. E. Baker, A. L. Ackelson, R. Niteck
A Functional Role For The Ventrolateral Prefrontal Cortex In Non-Spatial Auditory Cognition, Y. E. Cohen, B. E. Russ, S. J. Davis, A. E. Baker, A. L. Ackelson, R. Niteck
Dartmouth Scholarship
Spatial and non-spatial sensory information is hypothesized to be evaluated in parallel pathways. In this study, we tested the spatial and non-spatial sensitivity of auditory neurons in the ventrolateral prefrontal cortex (vPFC), a cortical area in the non-spatial pathway. Activity was tested while non-human primates reported changes in an auditory stimulus' spatial or non-spatial features. We found that vPFC neurons were reliably modulated during a non-spatial auditory task but were not modulated during a spatial auditory task. The degree of modulation during the non-spatial task correlated positively with the monkeys' behavioral performance. These results are consistent with the hypotheses that …
Microsaccade Rate Varies With Subjective Visibility During Motion-Induced Blindness, Po-Jang Hsieh, Peter U. Tse
Microsaccade Rate Varies With Subjective Visibility During Motion-Induced Blindness, Po-Jang Hsieh, Peter U. Tse
Dartmouth Scholarship
Motion-induced blindness (MIB) occurs when a dot embedded in a motion field subjectively vanishes. Here we report the first psychophysical data concerning effects of microsaccade/eyeblink rate upon perceptual switches during MIB. We find that the rate of microsaccades/eyeblink rises before and after perceptual transitions from not seeing to seeing the dot, and decreases before perceptual transitions from seeing it to not seeing it. In addition, event-related fMRI data reveal that, when a dot subjectively reappears during MIB, the blood oxygen-level dependent (BOLD) signal increases in V1v and V2v and decreases in contralateral hMT+. These BOLD signal changes observed upon perceptual …
The Sleeping Brain's Influence On Verbal Memory: Boosting Resistance To Interference, Jeffrey M. Ellenbogen, Justin C. Hulbert, Ying Jiang, Robert Stickgold
The Sleeping Brain's Influence On Verbal Memory: Boosting Resistance To Interference, Jeffrey M. Ellenbogen, Justin C. Hulbert, Ying Jiang, Robert Stickgold
Dartmouth Scholarship
Memories evolve. After learning something new, the brain initiates a complex set of post-learning processing that facilitates recall (i.e., consolidation). Evidence points to sleep as one of the determinants of that change. But whenever a behavioral study of episodic memory shows a benefit of sleep, critics assert that sleep only leads to a temporary shelter from the damaging effects of interference that would otherwise accrue during wakefulness. To evaluate the potentially active role of sleep for verbal memory, we compared memory recall after sleep, with and without interference before testing. We demonstrated that recall performance for verbal memory was greater …
Medial Temporal Lobe Bold Activity At Rest Predicts Individual Differences In Memory Ability In Hhealthy Young Adults, Gagan S. Wig, Scott T. Grafton, Kathryn E. Demos, George L. Wolford, Steven E. Petersen, William M. Kelley
Medial Temporal Lobe Bold Activity At Rest Predicts Individual Differences In Memory Ability In Hhealthy Young Adults, Gagan S. Wig, Scott T. Grafton, Kathryn E. Demos, George L. Wolford, Steven E. Petersen, William M. Kelley
Dartmouth Scholarship
Human beings differ in their ability to form and retrieve lasting long-term memories. To explore the source of these individual differences, we used functional magnetic resonance imaging to measure blood-oxygen-level-dependent (BOLD) activity in healthy young adults (n = 50) during periods of resting fixation that were interleaved with periods of simple cognitive tasks. We report that medial temporal lobe BOLD activity during periods of rest predicts individual differences in memory ability. Specifically, individuals who exhibited greater magnitudes of task-induced deactivations in medial temporal lobe BOLD signal (as compared to periods of rest) demonstrated superior memory during offline testing. This relationship …
Switching Language Switches Mind: Linguistic Effects On Developmental Neural Bases Of ‘Theory Of Mind’, Chiyoko Kobayashi, Gary H. Glover, Elise Temple
Switching Language Switches Mind: Linguistic Effects On Developmental Neural Bases Of ‘Theory Of Mind’, Chiyoko Kobayashi, Gary H. Glover, Elise Temple
Dartmouth Scholarship
Theory of mind (ToM)—our ability to predict behaviors of others in terms of their underlying intentions—has been examined through false-belief (FB) tasks. We studied 12 Japanese early bilingual children (8−12 years of age) and 16 late bilingual adults (18−40 years of age) with FB tasks in Japanese [first language (L1)] and English [second language (L2)], using fMRI. Children recruited more brain regions than adults for processing ToM tasks in both languages. Moreover, children showed an overlap in brain activity between the L1 and L2 ToM conditions in the medial prefrontal cortex (mPFC). Adults did not show such a convergent activity …
Detecting Agency From The Biological Motion Of Veridical Vs Animated Agents, Raymond A. Mar, William M. Kelley, Todd F. Heatherton, C. Neil Macrae
Detecting Agency From The Biological Motion Of Veridical Vs Animated Agents, Raymond A. Mar, William M. Kelley, Todd F. Heatherton, C. Neil Macrae
Dartmouth Scholarship
The ability to detect agency is fundamental for understanding the social world. Underlying this capacity are neural circuits that respond to patterns of intentional biological motion in the superior temporal sulcus and temporoparietal junction. Here we show that the brain's blood oxygenation level dependent (BOLD) response to such motion is modulated by the representation of the actor. Dynamic social interactions were portrayed by either live-action agents or computer-animated agents, enacting the exact same patterns of biological motion. Using an event-related design, we found that the BOLD response associated with the perception and interpretation of agency was greater when identical physical …
Prior Experience As A Stimulus Category Confound: An Example Using Facial Expressions Of Emotion, Leah H. Somerville, Paul J. Whalen
Prior Experience As A Stimulus Category Confound: An Example Using Facial Expressions Of Emotion, Leah H. Somerville, Paul J. Whalen
Dartmouth Scholarship
Facial expressions of emotion represent a stimulus set widely used to assess a broad range of psychological processes. However, a consideration of systematic differences between expression categories, other than differences relating to characteristics of the expressions themselves, has remained largely unaddressed. By collecting experience rankings in a large sample of undergraduates, we observed that the amount of reported experience individuals have had with different facial expressions of emotion systematically differed between all expression categories. These findings shed light on the potential for identifying confounds inherent to comparing some stimulus categories and, in this case, may aid in the interpretation of …
Medial Prefrontal Activity Differentiates Self From Close Others, Todd F. Heatherton, Carrie L. Wyland, C. Neil Macrae, Kathryn E. Demos, Bryan T. Denny, William M. Kelley
Medial Prefrontal Activity Differentiates Self From Close Others, Todd F. Heatherton, Carrie L. Wyland, C. Neil Macrae, Kathryn E. Demos, Bryan T. Denny, William M. Kelley
Dartmouth Scholarship
No abstract provided.
Visibility, Visual Awareness, And Visual Masking Of Simple Unattended Targets Are Confined To Areas In The Occipital Cortex Beyond Human V1/V2, Peter U. Tse, Susanna Martinez-Conde, Alexander A. Schlegel, Stephen L. Macknik
Visibility, Visual Awareness, And Visual Masking Of Simple Unattended Targets Are Confined To Areas In The Occipital Cortex Beyond Human V1/V2, Peter U. Tse, Susanna Martinez-Conde, Alexander A. Schlegel, Stephen L. Macknik
Dartmouth Scholarship
In visual masking, visible targets are rendered invisible by modifying the context in which they are presented, but not by modifying the targets themselves. Here, we localize the neuronal correlates of visual awareness in the human brain by using visual masking illusions. We compare monoptic visual masking activation, which we find within all retinotopic visual areas, with dichoptic masking activation, which we find only in those retinotopic areas downstream of V2. Because monoptic and dichoptic masking are equivalent in magnitude perceptually, the present results establish a lower bound for maintenance of visual awareness of simple unattended targets. Moreover, we find …
Donepezil Effects On Mood In Patients With Schizophrenia And Schizoaffective Disorder, S Craig Risch, Michael D. Horner, Susan R. Mcgurk, Simmy Palecko, John S. Markowitz, Ziad Nahas, C. Lindsay Devane
Donepezil Effects On Mood In Patients With Schizophrenia And Schizoaffective Disorder, S Craig Risch, Michael D. Horner, Susan R. Mcgurk, Simmy Palecko, John S. Markowitz, Ziad Nahas, C. Lindsay Devane
Dartmouth Scholarship
Donepezil, 5 mg/d for 6 wk then 10 mg/d for 6 wk, and placebo daily for 12 wk in a double-blind cross-over paradigm, was added to the therapeutic regimen of 13 patients with schizophrenia or schizoaffective disorders, clinically stable on atypical antipsychotic medications. Patients had varying degrees of depressive symptoms, ranging from no depression to clinically significant depression. There was no worsening or induction of depression in individual patients or the group as a whole. In addition there was a statistically significant antidepressant effect in the group as a whole during the donepezil condition and a clinically significant antidepressant effect …
Il-23 Produced By Cns-Resident Cells Controls T Cell Encephalitogenicity During The Effector Phase Of Experimental Autoimmune Encephalomyelitis, Burkhard Becher, Brigit G. Durell, Randolph J. Noelle
Il-23 Produced By Cns-Resident Cells Controls T Cell Encephalitogenicity During The Effector Phase Of Experimental Autoimmune Encephalomyelitis, Burkhard Becher, Brigit G. Durell, Randolph J. Noelle
Dartmouth Scholarship
CNS-resident cells, in particular microglia and macrophages, are a source of inflammatory cytokines during inflammation within the CNS. Expression of IL-23, a recently discovered cytokine, has been shown to be critical for the development of experimental autoimmune encephalomyelitis (EAE) in mice. Expression of the p40 subunit of IL-12 and IL-23 by microglia has been shown in situ and in vitro, but direct evidence for a functional significance of p40 expression by CNS cells during an immune response in vivo is still lacking. Here we report that p40 plays a critical role in maintaining encephalitogenicity during the disease course. By using …
Distinct Neural Systems Subserve Person And Object Knowledge, Jason P. Mitchell, Todd F. Heatherton, C. Neil Macrae
Distinct Neural Systems Subserve Person And Object Knowledge, Jason P. Mitchell, Todd F. Heatherton, C. Neil Macrae
Dartmouth Scholarship
Studies using functional neuroimaging and patient populations have demonstrated that distinct brain regions subserve semantic knowledge for different classes of inanimate objects (e.g., tools, musical instruments, and houses). What this work has yet to consider, however, is how conceptual knowledge about people may be organized in the brain. In particular, is there a distinct functional neuroanatomy associated with person knowledge? By using event-related functional magnetic resonance imaging (fMRI), we measured neural activity while participants made semantic judgments about people or objects. A unique pattern of brain activity was associated with person judgments and included brain regions previously implicated in other …
The Interaction Between Cytoplasmic Dynein And Dynactin Is Required For Fast Axonal Transport, Clare M. Waterman-Storer, Sher B. Karki, Sergei A. Kuznetsov, Joel S. Tabb, Dieter G. Weiss, George M. Langford, Erika L. F. Holzbaur
The Interaction Between Cytoplasmic Dynein And Dynactin Is Required For Fast Axonal Transport, Clare M. Waterman-Storer, Sher B. Karki, Sergei A. Kuznetsov, Joel S. Tabb, Dieter G. Weiss, George M. Langford, Erika L. F. Holzbaur
Dartmouth Scholarship
Fast axonal transport is characterized by the bidirectional, microtubule-based movement of membranous organelles. Cytoplasmic dynein is necessary but not sufficient for retrograde transport directed from the synapse to the cell body. Dynactin is a heteromultimeric protein complex, enriched in neurons, that binds to both microtubules and cytoplasmic dynein. To determine whether dynactin is required for retrograde axonal transport, we examined the effects of anti-dynactin antibodies on organelle transport in extruded axoplasm. Treatment of axoplasm with antibodies to the p150(Glued) subunit of dynactin resulted in a significant decrease in the velocity of microtubule-based organelle transport, with many organelles bound along microtubules. …
Head Direction Cells And Episodic Spatial Information In Rats Without A Hippocampus, Edward J. Golob, Jeffrey S. Taube
Head Direction Cells And Episodic Spatial Information In Rats Without A Hippocampus, Edward J. Golob, Jeffrey S. Taube
Dartmouth Scholarship
To successfully navigate through the environment animals rely on information concerning their directional heading and location. Many cells within the postsubiculum and anterior thalamus discharge as a function of the animal’s head direction (HD), while many cells in the hippocampus discharge in relation to the animal’s location. We placed lesions in the hippocampus and recorded from HD cells in the postsubiculum and anterior thalamus. Lesions of the hippocampus did not disrupt the HD cell signal in either brain area, indicating that the HD cell signal must be generated by structures external to the hippocampus. In addition, each cell’s preferred firing …