Mutable Brain: Dynamic and Plastic Features of the Developing and Mature Brain (Brain Plasticity and Reorganization) (v. 1)

Book Cover......Page 1
Half-Title......Page 2
Title......Page 4
Copyright......Page 5
Contents......Page 6
Series Preface......Page 7
Preface......Page 9
Contributors......Page 11
1. INTRODUCTION......Page 14
2. ASSUMPTIONS AND TECHNICAL LIMITATIONS......Page 15
2.1. Choice of Species......Page 16
2.2. Stages of Development and Critical Periods......Page 17
2.3.1. Technical Considerations......Page 18
2.5. Linking Assumptions......Page 19
3.1. Early Stages: Activity Independent Developmental Events......Page 20
3.2. Later Stages: Positional Cues and Activity Dependent Developmental Events......Page 25
4. DEVELOPMENT ALTERED BY SELECTIVE VISUAL DEPRIVATION......Page 28
4.1. Lid Closure: Central Changes......Page 29
4.2. Binocular Suture and Dark Rearing......Page 33
4.3. Lid Closure: Eye Development and Myopia......Page 34
4.4. Other Manipulations of the Visual Diet......Page 36
4.5. Proposed Mechanisms......Page 38
5.1. Ennucleation: Effects of Early Eye Loss......Page 43
5.2. Cortical Lesions......Page 47
5.3. Subcortical Lesions......Page 50
6. CONCLUSIONS AND SUMMARY......Page 51
REFERENCES......Page 53
2. PRINCIPLES OF SYNAPTIC TRANSMISSION AND SHORT-TERM PLASTICITY......Page 70
2.1. Release of Glutamate......Page 71
2.1.1. Short-term plasticity of glutamate release......Page 72
2.2. Postsynaptic Response to Glutamate......Page 74
2.2.1. Glutamate-gated ion channels......Page 75
2.2.3. Short-term plasticity of glutamate responses......Page 77
3. LONG-TERM PLASTICITY OF GLUTAMATERGIC SYNAPTIC TRANSMISSION......Page 78
3.1.1. Methodology......Page 79
3.1.2. LTP induction......Page 80
3.1.3. LTP expression......Page 84
3.1.4. LTP maintenance......Page 90
3.2. Long-Term Depression in the CA1 Region of Hippocampus......Page 92
3.2.1. LTD induction......Page 94
3.2.2. LTD expression......Page 95
3.3. Metaplasticity......Page 96
3.3.3. Evidence for metaplasticity in the visual cortex......Page 97
3.3.4. Intracellular mechanisms for the sliding threshold......Page 99
4. FUNCTIONAL SIGNIFICANCE OF LTP AND LTD......Page 101
4.1. LTP/D in Development and Experience-Dependent Plasticity......Page 102
4.2. LTP/D in Learning and Memory......Page 103
ACKNOWLEDGEMENTS......Page 105
REFERENCES......Page 106
1. INTRODUCTION......Page 119
2. SPATIOTEMPORAL RFS AS THE UNDERLYING SUBSTRATE FOR IMMEDIATE SENSORY PLASTICITY......Page 120
3. CIRCUIT MECHANISMS INVOLVED IN THE GENESIS OF SPATIOTEMPORAL RFS IN THE RAT SOMATOSENSORY SYSTEM......Page 125
4. SHORT-TERM SENSORY PLASTICY IN THE RAT TRIGEMINAL SOMATOSENSORY SYSTEM......Page 128
5. BEHAVIORAL MODULATION OF SOMATOSENSORY RESPONSES......Page 136
6. MOVING FROM SHORT TO LONG-TERM PLASTICITY......Page 141
7. WHY IS IT IMPORTANT TO UNDERSTAND THE TIME COURSE OF SENSORY PLASTICITY?......Page 144
REFERENCES......Page 145
1. INTRODUCTION......Page 153
1.1. Why Study the Whisker System?......Page 154
2.1. How Are Whiskers Used?......Page 156
3.1. Trigeminal Brainstem Nuclear Complex Projections to Thalamus and Cortex......Page 159
3.2. Cerebellar Efferents......Page 161
3.3. Efferent Projections of the Barrel Cortex......Page 162
3.4. Projections from the Vibrissal Region of Motor Cortex......Page 163
3.6. Sensory and Motor Convergence......Page 165
4.1.1. Trigeminal ganglion cells......Page 166
4.1.3. Thalamus......Page 167
4.1.4. Cortex......Page 168
4.1.5. Other subcortical structures......Page 169
4.4. Adaptation Properties of Vibrissa Related Neurons......Page 170
4.6. Directional Selectivity......Page 171
5. PLASTICITY IN THE VIBRISSAL CORTEX: CAN THE WHISKER REPRESENTATION BE MODIFIED BY EXPERIENCE?......Page 173
6. WHAT CAN WE LEARN FROM STUDIES OF AWAKE, BEHAVING ANIMALS?......Page 175
6.1. Awake Rat S1 Cortex......Page 176
6.3. Multiple Recordings from the Trigeminal Neuraxis in Awake Rodents......Page 177
7. WHISKING BEHAVIOR: ADVANCES IN CONTROL AND MEASUREMENT......Page 178
8. DO MULTIPLE REPRESENTATIONS REFLECT MULTIPLE FUNCTIONS?......Page 183
9. UNANSWERED QUESTIONS IN THE VIBRISSAL SENSORIMOTOR SYSTEM?......Page 188
REFERENCES......Page 191
1. INTRODUCTION......Page 202
2. BRAIN MAPS ARE NORMALLY STABLE......Page 204
3.1 Normal Organization......Page 206
3.2 Reorganization of Somatosensory Cortex Due to Sensory Experience......Page 207
3.3.1. Digit loss......Page 210
3.3.2. Section of sensory nerves of the hand......Page 213
3.3.3. Nerve regeneration......Page 216
3.3.4. Limb deafferentation......Page 218
3.3.5. Dorsal column sections......Page 222
3.3.6. Cortical ablations......Page 224
3.4 Subcortical Plasticity......Page 226
4.1 Cortical Reorganization after Retinal Lesions......Page 231
4.3. Reorganization in the Lateral Geniculate Nucleus......Page 234
5.1 Plasticity in Auditory Cortex......Page 235
6. MOTOR CORTEX REORGANIZATION......Page 238
6.1 Plasticity in the Other Sensory Systems......Page 241
7. MECHANISMS OF PLASTICITY......Page 242
7.1.1. Dynamic Regulation of Receptive Field Sizes and Properties......Page 243
7.1.3. Neuromodulation from extrinsic sources......Page 245
7.1.4. Other Short-term Changes in Synaptic Efficacy......Page 247
7.1.5. Long-term Potentiation, Long-term Depression, and Hebbian-like Plasticity......Page 248
7.1.6. Activity based regulation of inhibition......Page 249
7.1.7. Activity-based regulation of excitation......Page 250
7.2.1. Dendritic growth and modification......Page 251
7.2.2. Axon growth......Page 252
8. FUNCTIONAL CONSEQUENCES OF PLASTICITY......Page 256
8.1 Perceptual Learning and Motor Skills......Page 257
8.2. Recovery from Brain Damage and Sensory Loss......Page 258
8.3. Focal Dystonias......Page 259
8.4. Phantom Sensations and Mislocalizations......Page 260
9. CONCLUSIONS......Page 263
REFERENCES......Page 265
1. INTRODUCTION......Page 293
2.1.1. Behavioral evidence......Page 294
2.1.2. Neural changes in visually deprived cats......Page 295
2.2.1. Behavioral evidence for auditory compensation in blind humans......Page 297
2.2.2. Neuroimaging studies in blind humans......Page 299
2.3. Comparison of Human and Animal Data......Page 300
3.1.1. Tactile behavior in visually deprived animals......Page 301
3.1.2. Tactile compensation in blind animals......Page 302
3.2. Human Studies of Tactile Compensation......Page 304
4. CROSSMODAL COMPENSATION IN THE DEAF......Page 306
5. CONCLUDING REMARKS......Page 307
REFERENCES......Page 308
1. INTRODUCTION......Page 313
2.2. New Anatomy-Connections Between Cortical and Hippocampal Structures......Page 315
2.3. What Information is Transmitted to Hippocampus from the Cortex?......Page 318
3.1. Potentiation and Depression in Hippocampal Synaptic Connections......Page 319
3.2. New Dynamics of Hippocampal Synaptic interactions......Page 321
4.1. What is Disrupted by Hippocampal Removal or Damage?......Page 322
4.2. Is the Hippocampus Part of the Memory Circuit?......Page 324
5.1.1. What are place fields?......Page 327
5.1.2. What information is encoded in place fields?......Page 328
5.1.3. Factors affecting place cell plasticity......Page 329
5.1.5. Place cells: some remaining issues......Page 330
5.1.6. “Navigation” and place fields examined from a behavioral perspective......Page 332
5.2. Nonspatial Correlates of Hippocampal Cell Firing......Page 333
5.2.1. Task-relevant factors control hippocampal cell firing......Page 334
5.2.2. Integration of spatial and task-relevant firing......Page 335
6.1. Hippocampal Encoding During DNMS Performance......Page 337
6.2. Nature of Hippocampal Ensemble Codes......Page 339
6.3. WHAT IS “REPRESENTED” IN THE HIPPOCAMPAL ENSEMBLE CODE......Page 341
6.4 Delay Firing and Hippocampal Ensemble Activity......Page 344
6.4. Anatomic Representation of Memory in Hippocampus: What is the Default Code?......Page 345
7. SUMMARY AND CONCLUSIONS......Page 346
ACKNOWLEDGMENTS......Page 347
REFERENCES......Page 348
NOTES......Page 364
1. INTRODUCTION......Page 365
2. BIRD SONG AND ITS DEVELOPMENT......Page 366
3. ANATOMY OF THE ADULT SONG SYSTEM......Page 371
4. JUVENILE PLASTICITY IN THE SONG SYSTEM......Page 374
4.1. Changes in Nuclear Volume and Neuronal Number......Page 375
4.2. Changes in Neuronal Connections and Dendritic Spines......Page 377
4.3 Changes in Neurochemistry......Page 379
4.4. Changes in Neurophysiology......Page 380
4.5. Changes in the Behavioral Effects of Brain Lesions......Page 385
4.6. Causality from Correlation......Page 386
5. ADULT PLASTICITY IN THE SONG SYSTEM......Page 391
6. VOCAL LEARNING IN PARROTS......Page 395
7. CONCLUSION......Page 399
ACKNOWLEDGMENTS......Page 402
REFERENCES......Page 403
NOTES......Page 413
2. ROLE OF VISUALLY DRIVEN AND SPONTANEOUS NEURAL ACTIVITY IN THE DEVELOPMENT AND PLASTICITY OF CORTICAL CIRCUITRY AND FUNCTION......Page 414
2.1.1. Ocular dominance columns and bands......Page 415
2.1.2. Role of visual experience......Page 416
2.1.3. Role of spontaneous neural activity......Page 419
2.2.1. Orientation selectivity and maps......Page 422
2.2.2. Role of visual experience......Page 424
2.2.3. Role of spontaneous neural activity......Page 427
2.3.1. Development of horizontal connections......Page 428
2.3.2. Role of spontaneous and visually-guided neural activity......Page 431
3. ROLE OF PATTERNED AFFERENT ACTIVITY IN THE DEVELOPMENT OF CORTICAL CIRCUITS AND FUNCTIONS......Page 432
3.1. Artificial Strabismus......Page 433
3.2. Artificial Stimulation of the Optic Nerves......Page 435
3.3. Cross-modal Plasticity......Page 437
3.3.1. Activity-dependent sorting of retinothalamic projections and thalamocortical synapses......Page 438
3.3.2. Orientation selectivity and orientation maps in rewired cortex......Page 441
3.3.3. Visual behavior mediated by the rewired pathway......Page 448
REFERENCES......Page 449
Subject Index......Page 461