Dorsolateral Prefrontal Cortex: Working Memory and Executive Functions

Preface
Acknowledgments
Contents
Chapter 1: Dorsolateral Prefrontal Cortex
	1.1 Introduction
	1.2 The Prefrontal Cortex
	1.3 Features of the Prefrontal Cortex
	1.4 Anatomical Features of the Prefrontal Cortex
		1.4.1 Cytoarchitectonic Features
		1.4.2 Cytoarchitectonic Features of the Lateral Prefrontal Cortex
		1.4.3 Relations to the Thalamic Mediodorsal Nucleus
		1.4.4 Granular Layer IV
		1.4.5 Mesulam´s Cortical Classification
	1.5 Anatomical Features of the Lateral Prefrontal Cortex
		1.5.1 Cellular Components
			1.5.1.1 Pyramidal Neurons
			1.5.1.2 Nonpyramidal Neurons
			1.5.1.3 Interactions Between Pyramidal and Nonpyramidal Neurons
			1.5.1.4 Modulation of Activity by Catecholamine and Monoamine
		1.5.2 Anatomical Heterogeneity in Area 46
		1.5.3 Cortico-Cortical Connections
			1.5.3.1 Afferent Connections
			1.5.3.2 Efferent Connections
			1.5.3.3 Callosal Connections
		1.5.4 Cortico-Subcortical Connections
			1.5.4.1 Anatomical Connections with the Thalamus
			1.5.4.2 Prefrontal Connections with the Basal Ganglia
			1.5.4.3 Prefrontal Connections with Other Subcortical Structures
		1.5.5 Intracortical Structures: Columnar Organization
	1.6 Functional Features of the Lateral Prefrontal Cortex
		1.6.1 Human Prefrontal Functions
		1.6.2 Functional Heterogeneity of the Prefrontal Cortex
		1.6.3 Functional Heterogeneity in Human Prefrontal Cortex
		1.6.4 Functional Development of the Prefrontal Cortex
	References
Chapter 2: Historical Perspective of Prefrontal Research
	2.1 Functional Localization of the Cerebral Cortex
	2.2 Historical Perspective of Frontal Lobe Functions
		2.2.1 Debate Between Holistic Theory and Localization Theory
		2.2.2 Functions of the Frontal Lobe
		2.2.3 Lashley´s Principles: Equipotentiality and Mass Action
		2.2.4 The Prefrontal Cortex Has Some Specific Function
		2.2.5 Jacobsen´s Experiments Using Delayed-Response Task
		2.2.6 Delayed-Response Deficits Caused by Prefrontal Lesions
		2.2.7 Localization of the Cortical Area Responsible for Delayed-Response Performance
		2.2.8 Delayed-Response Deficits Can Be Observed in Human Prefrontal Patients
		2.2.9 Delayed-Response Deficits Can Also Be Observed in Rats and Dogs
	2.3 Behavioral Deficits in Other Delay Tasks Caused by Prefrontal Lesions
		2.3.1 Delayed Alternation Task and Importance of Spatial Factor
		2.3.2 Delayed Matching-to-Sample Task and Other Delay Tasks
	2.4 Cryogenic Depression of Prefrontal Functions
	2.5 What Causes Delayed-Response Deficits?
		2.5.1 Factors Affecting Delayed-Response Performances
		2.5.2 Increased Susceptibility, Distractibility, and Hyperactivity to Irrelevant Stimuli
		2.5.3 Kinesthetic Effects
	2.6 Mnemonic Hypothesis of Prefrontal Function
		2.6.1 Problems of Behavior Control During the Delay Period
		2.6.2 An Oculomotor Version of the Delayed-Response Task
		2.6.3 Mnemonic Scotoma Observed in Prefrontal Lesioned Monkeys
		2.6.4 Contralateral Bias of Spatial Mnemonic Process in the Prefrontal Cortex
		2.6.5 Working Memory Is an Important Function of the Prefrontal Cortex
	References
Chapter 3: Working Memory and Prefrontal Functions
	3.1 Introduction
	3.2 Short-Term Memory and Working Memory
		3.2.1 Modal Model of Human Memory
		3.2.2 Baddeley and Hitch´s Experiment
	3.3 Working Memory
		3.3.1 Working Memory Model Proposed by Baddeley
		3.3.2 Other Models and Definitions of Working Memory
		3.3.3 Working Memory in Animal Studies
			3.3.3.1 Working Memory Versus Reference Memory
			3.3.3.2 Spatial Working Memory Tasks
			3.3.3.3 Non-spatial Working Memory Tasks and Recognition Memory Tasks
		3.3.4 Advantages of Delayed-Response Task in Searching Neural Mechanisms of Working Memory
		3.3.5 Working Memory As an Important Concept for Prefrontal Functions
	3.4 Working Memory in the Prefrontal Cortex
		3.4.1 Search for Neural Correlates of Working Memory in the Prefrontal Cortex
		3.4.2 Kubota´s and Fuster´s Studies in the Prefrontal Cortex
		3.4.3 Differential Delay-Period Activity.
		3.4.4 Delay-Period Activity Is a Neural Correlate of the Mnemonic Process in the Prefrontal Cortex?
		3.4.5 Differential Delay-Period Activity As a Neural Correlate of Mnemonic Process?
	3.5 An oculomotor Delayed-Response Task
		3.5.1 The Oculomotor Delayed-Response Task
		3.5.2 Task-Related Prefrontal Activity in the ODR Task
	3.6 Delay-Period Activity in the ODR Task
		3.6.1 Sustained Nature of Delay-Period Activity
		3.6.2 Directional Selectivity
		3.6.3 Robustness of Delay-Period Activity
		3.6.4 Learning Effects
		3.6.5 Delay-Period Activity Is a Neural Correlate of Working Memory Process
		3.6.6 Mnemonic Receptive Field
		3.6.7 Delay-Period Activity Represents Retrospective and Prospective Information
		3.6.8 Delay-Period Activity Represents Relative or Absolute Spatial Information
	3.7 Delay-Period Activity Encoding Non-spatial Visual Information
		3.7.1 Delay-Period Activity in Non-spatial Visual Working Memory Tasks
		3.7.2 Delay-Period Activity Representing Object Categories.
		3.7.3 Robustness of Delay-Period Activity
		3.7.4 Retrospective Coding Versus Prospective Coding
		3.7.5 Interactions Between Spatial and Non-spatial Information
	3.8 Delay-Period Activity Encoding Somatosensory Information
	3.9 Delay-Period Activity Representing Motor Information
	3.10 Delay-Period Activity Representing Task Difference and Behavioral Rule
	3.11 Delay-Period Activity Representing Reward Expectation
	3.12 Delay-Period Activity Representing Temporal Order of Stimulus Presentation
	3.13 Delay-Period Activity Representing Numerical Quantity
	3.14 Delay-Period Activity Representing Relative Distance Between Stimuli
	3.15 Delay-Period Activity Representing Estimation of Behavioral Timing
	3.16 Information Processing in Working Memory
		3.16.1 Information Represented by Delay-Period Activity Changes
		3.16.2 Population-Vector Analysis
		3.16.3 Population-Vector Analysis of Delay-Period Activity
		3.16.4 What Causes the Rotation of the Population Vector during the Delay Period?
		3.16.5 Interaction Between Delay-Period Activity and Saccade-Related Activity
		3.16.6 Integration of Multiple Information
		3.16.7 Dynamic Changes of Functional Interactions Among Prefrontal Neurons
	3.17 Delay-Period Activity Observed in Other Brain Areas
		3.17.1 Frontal Eye Field
		3.17.2 Orbitofrontal Cortex
		3.17.3 Parietal Cortex
		3.17.4 Inferior Temporal Cortex
		3.17.5 Other Cortical Areas
		3.17.6 Thalamus
		3.17.7 Basal Ganglia
		3.17.8 Other Subcortical Areas
	3.18 Delay-Period Activity Is a Neural Mechanism for Temporarily Maintaining Information
	References
Chapter 4: Executive Control
	4.1 Introduction
	4.2 What Is Executive Control?
	4.3 Executive Control and the Prefrontal Cortex
		4.3.1 Wisconsin Card Sorting Test
		4.3.2 Tower of London Test
		4.3.3 Self-Ordered Test
		4.3.4 Other Tests Sensitive to Prefrontal Functions
		4.3.5 Prefrontal Contribution to Executive Control
	4.4 Executive Control by the Prefrontal Cortex
		4.4.1 Control of Attention
			4.4.1.1 Attention-Related Activity Observed in the Prefrontal Cortex
			4.4.1.2 Attention-Related Activity in the Frontal Eye Field
			4.4.1.3 Top-Down Control of Visual Information Processing by the Frontal Eye Field
			4.4.1.4 Top-Down Control of Visual Information Processing by the Prefrontal Cortex
		4.4.2 Inhibitory Control
			4.4.2.1 Anti-Saccade Task
			4.4.2.2 Stop-Signal Paradigm
			4.4.2.3 No-Go Dominant Activity
			4.4.2.4 Conflict Conditions
		4.4.3 Task Management
		4.4.4 Shifting Stimulus or Action Categories
		4.4.5 Planning
	4.5 How Does the Prefrontal Cortex Achieve Executive Control?
	4.6 Interactions between the Prefrontal Cortex and Other Cortical Areas
	4.7 Conclusions
	References
Chapter 5: Sensory and Motor Processing
	5.1 Sensory Processing
		5.1.1 Visual Processing
			5.1.1.1 Characteristics of Visual Responses
			5.1.1.2 Topographic Representation of Visual Response Features
			5.1.1.3 Cue-Period Activity Observed During Performance of Cognitive Tasks
				5.1.1.3.1 Visual Responses Observed During Delayed-Response Performances
				5.1.1.3.2 Visual Responses in the ODR Task
				5.1.1.3.3 Visual Responses in Matching-to-Sample Tasks and Discrimination Tasks
			5.1.1.4 Discrimination of Relevant Visual Stimuli from Irrelevant Ones
			5.1.1.5 Behavioral Context-Dependent Visual Responses
		5.1.2 Auditory Processing
			5.1.2.1 Auditory Projections to the Prefrontal Cortex
			5.1.2.2 Auditory Responses in the Prefrontal Cortex
			5.1.2.3 Selectivity of Auditory Responses and Participation in Vocal Communication
		5.1.3 Somatosensory Processing
	5.2 Skeletomotor Control
		5.2.1 Anatomical Connections Between the Prefrontal Cortex and Cortical Motor Areas
		5.2.2 Movement-Related Activity in the Prefrontal Cortex
		5.2.3 Response-Period Activity Is Context Dependent
	5.3 Eye Movement Control
		5.3.1 Historical Perspective on the Prefrontal Contribution to Eye Movement Control
			5.3.1.1 Effects of Electrical Stimulation in the Frontal Lobe
			5.3.1.2 Saccade-Related Single-Neuron Activity in the Frontal Eye Field
		5.3.2 Saccade-Related Activity in the Dorsolateral Prefrontal Cortex
		5.3.3 Comparison of Saccade-Related Activity Between the Prefrontal Cortex and the Frontal Eye Field
		5.3.4 Contribution of Post-Saccadic Activity in Cognitive Functions
			5.3.4.1 Post-Trial Activity Observed in the Prefrontal Cortex
			5.3.4.2 Post-Saccadic Activity Has Function to Terminate Delay-Period Activity
			5.3.4.3 Post-Saccadic Activity May Participate in Performance Monitoring
		5.3.5 Other Features of Prefrontal Saccade-Related Activity
	References
Chapter 6: Cognitive Control
	6.1 Dual-Task Interference, Interference Control, and Cognitive Control
	6.2 Theories of Cognitive Resource
		6.2.1 Overlap Hypothesis: Modality-Specific Multiple Resource Model
		6.2.2 Modality-General Single Resource Model
	6.3 Dual-Task Paradigm as a Tool to Examine Dual-Task Interference
	6.4 Prefrontal Cortex and Dual-Task Performance
		6.4.1 Human Neuropsychological Studies
		6.4.2 Human fMRI Studies
		6.4.3 Is the Prefrontal Cortex a Specific Area for Dual-Task Performance?
		6.4.4 Limitations of Neuroimaging Studies
	6.5 Search for Neural Mechanisms of Dual-Task Interference by Animal Studies
		6.5.1 Advantages of Animal Studies
		6.5.2 Behavioral Studies Using Rats
		6.5.3 Behavioral Studies Using Monkeys
	6.6 Neural Mechanisms of Dual-Task Interference
		6.6.1 Rats
		6.6.2 Monkeys
		6.6.3 Researches by Wise and Colleagues
		6.6.4 Researches by Watanabe and Funahashi
			6.6.4.1 Dual-Task Paradigm
			6.6.4.2 Behavioral Performance
			6.6.4.3 Single-Neuron Activity
			6.6.4.4 Temporal Dynamics of Adaptive Allocation of Cognitive Resource
	6.7 What Is Next?
	References
Chapter 7: Decision-Making
	7.1 Decision-Making
		7.1.1 Memory-Based Decision-Making
		7.1.2 Value-Based Decision-Making
		7.1.3 Free-Choice Decision-Making
	7.2 Prefrontal Contribution to Free-Choice Decision-Making: Human Imaging Studies
	7.3 Prefrontal Contribution to Free-Choice Decision-Making: Animal Physiological Studies
		7.3.1 Neural Correlates of Free-Choice Decision-Making in the Prefrontal Cortex
		7.3.2 Study by Watanabe et al. (2006)
		7.3.3 Studies by Mochizuki and Funahashi (2014, 2016)
		7.3.4 Choice-Predictive Activity in the Prefrontal Cortex
		7.3.5 Anticipatory Bias and Pre-Stimulus Activity
		7.3.6 What Causes Choice-Predictive Activity?
		7.3.7 Functional Relations Between Choice-Predictive Activity and Delay-Period Activity
	7.4 Neural Mechanism for Free-Choice Decision-Making in the Prefrontal Cortex
	7.5 Prefrontal Contribution to Other Types of Decision-Making
		7.5.1 Perceptual Decision-Making
		7.5.2 Value-Based Decision-Making
		7.5.3 Decision-Making Under Competitive Conditions
		7.5.4 Decision-Making in Conflict Conditions
	7.6 Conclusions
	References
Chapter 8: Metacognition
	8.1 Metacognition
	8.2 Metamemory
	8.3 Metamemory: Human Studies
	8.4 Prefrontal Contribution to Metamemory and Metacognition
		8.4.1 Human Neuropsychological Studies
		8.4.2 Human Brain Imaging Studies
	8.5 Metamemory Studies Using Non-Human Animals
		8.5.1 Behavioral Paradigms for Animal Studies
			8.5.1.1 Prospective Paradigm
			8.5.1.2 Experiments by Smith et al.
			8.5.1.3 Experiments by Hampton
			8.5.1.4 Experiments by Fujita
		8.5.2 Retrospective Paradigms
	8.6 Examination of Neural Mechanisms of Metamemory
		8.6.1 Experiment by Tanaka and Funahashi (2012)
		8.6.2 Experiments by Middlebrooks and Sommer (2011, 2012)
		8.6.3 Experiments by Miyamoto et al. (2017, 2018)
		8.6.4 Metacognition and Confidence Judgment
	8.7 Conclusions
	References
Chapter 9: Top-Down Control
	9.1 Evidences of Top-Down Control by the Prefrontal Cortex
	9.2 Top-Down Control and Contribution of the Prefrontal Cortex
		9.2.1 Top-Down Interactions between the Prefrontal Cortex and Other Cortical and Subcortical Areas
			9.2.1.1 Reversible Inactivation Studies
			9.2.1.2 TMS Studies
		9.2.2 Top-Down Control of Attention by the Prefrontal Cortex
			9.2.2.1 Top-Down Control of Attention by the Frontal Eye Field
			9.2.2.2 Top-Down Control of Attention by the Dorsolateral Prefrontal Cortex
		9.2.3 Top-Down Control of Object Recognition by the Prefrontal Cortex
		9.2.4 Top-Down Modulation of Long-Term Memory Process by the Prefrontal Cortex
	9.3 Search for Top-Down Signals in the Prefrontal Cortex
		9.3.1 Neural Activity Related to Long-Term Memory in the Inferior Temporal Cortex
		9.3.2 Prefrontal Activity During a Visual Paired Association Task
			9.3.2.1 Prefrontal Activity During the Sample Period
			9.3.2.2 Prefrontal Activity During the Delay Period
	9.4 Conclusions
	References
Chapter 10: Prefrontal Cortex and Working Memory
	10.1 Baddeley´s Working Memory Model
	10.2 Physiologically Plausible Model of Working Memory
	10.3 Working Memory-Related Activities in the Prefrontal Cortex
	10.4 A Process-Based Model of Working Memory
	10.5 Temporary Information-Storage Process
	10.6 Information Processing
		10.6.1 Temporal Change of Delay-Period Activity Along the Delay Period
		10.6.2 Delay-Period Activity Representing Composite Information
		10.6.3 Interactions Among Neurons Having Different Task-Related Activity
		10.6.4 Information Transformation During the Delay Period
	10.7 Interactions Among Prefrontal Neurons
		10.7.1 Information Flow During a Trial
		10.7.2 Dynamic Modulation of Functional Interactions Among Neurons
	10.8 Process-Based Model of Working Memory Can Be Applied to Many Information Processes
	10.9 Hierarchical Model of Working Memory
	10.10 Dynamic Interactions Between the Prefrontal Cortex and Other Cortical Areas
		10.10.1 Anatomical Evidences
		10.10.2 Non-Invasive Brain Imaging Studies
		10.10.3 Top-Down Modulation
	10.11 Conclusions
	References