Author
Neal J. Cohen
Other affiliations: University of California, San Diego, Massachusetts Institute of Technology, Johns Hopkins University ...read more
Bio: Neal J. Cohen is an academic researcher from University of Illinois at Urbana–Champaign. The author has contributed to research in topics: Amnesia & Cognition. The author has an hindex of 73, co-authored 218 publications receiving 29871 citations. Previous affiliations of Neal J. Cohen include University of California, San Diego & Massachusetts Institute of Technology.
Topics: Amnesia, Cognition, Semantic memory, Explicit memory, Recall
Papers published on a yearly basis
Papers
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TL;DR: In this article, the authors discuss the catastrophic interference in connectionist networks and show that new learning may interfere catastrophically with old learning when networks are trained sequentially, and the analysis of the causes of interference implies that at least some interference will occur whenever new learning might alter weights involved in representing old learning.
Abstract: Publisher Summary Connectionist networks in which information is stored in weights on connections among simple processing units have attracted considerable interest in cognitive science. Much of the interest centers around two characteristics of these networks. First, the weights on connections between units need not be prewired by the model builder but rather may be established through training in which items to be learned are presented repeatedly to the network and the connection weights are adjusted in small increments according to a learning algorithm. Second, the networks may represent information in a distributed fashion. This chapter discusses the catastrophic interference in connectionist networks. Distributed representations established through the application of learning algorithms have several properties that are claimed to be desirable from the standpoint of modeling human cognition. These properties include content-addressable memory and so-called automatic generalization in which a network trained on a set of items responds correctly to other untrained items within the same domain. New learning may interfere catastrophically with old learning when networks are trained sequentially. The analysis of the causes of interference implies that at least some interference will occur whenever new learning may alter weights involved in representing old learning, and the simulation results demonstrate only that interference is catastrophic in some specific networks.
3,119 citations
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TL;DR: The results indicate that the class of preserved learning skills in amnesia is broader than previously reported and support the hypothesis that such a distinction is honored by the nervous system.
Abstract: Amnesic patients acquired a mirror-reading skill at a rate equivalent to that of matched control subjects and retained it for at least 3 months. The results indicate that the class of preserved learning skills in amnesia is broader than previously reported. Amnesia seems to spare information that is based on rules or procedures, as contrasted with information that is data-based or declarative--"knowing how rather than "knowing that." The results support the hypothesis that such a distinction is honored by the nervous system.
2,204 citations
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TL;DR: It is demonstrated for the first time to the authors' knowledge, in humans that increases in cardiovascular fitness results in increased functioning of key aspects of the attentional network of the brain during a cognitively challenging task.
Abstract: Cardiovascular fitness is thought to offset declines in cognitive performance, but little is known about the cortical mechanisms that underlie these changes in humans. Research using animal models shows that aerobic training increases cortical capillary supplies, the number of synaptic connections, and the development of new neurons. The end result is a brain that is more efficient, plastic, and adaptive, which translates into better performance in aging animals. Here, in two separate experiments, we demonstrate for the first time to our knowledge, in humans that increases in cardiovascular fitness results in increased functioning of key aspects of the attentional network of the brain during a cognitively challenging task. Specifically, highly fit (Study 1) or aerobically trained (Study 2) persons show greater task-related activity in regions of the prefrontal and parietal cortices that are involved in spatial selection and inhibitory functioning, when compared with low-fit (Study 1) or nonaerobic control (Study 2) participants. Additionally, in both studies there exist groupwise differences in activation of the anterior cingulate cortex, which is thought to monitor for conflict in the attentional system, and signal the need for adaptation in the attentional network. These data suggest that increased cardiovascular fitness can affect improvements in the plasticity of the aging human brain, and may serve to reduce both biological and cognitive senescence in humans.
1,550 citations
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01 Jan 1993
TL;DR: A cognitive neuroscience theory of memory is offered that accounts for the nature of memory impairment exhibited in human amnesia and animal models of amnesia, that specifies the functional role played by the hippocampal system in memory, and that provides further understanding of the componential structure of memory.
Abstract: In this text, Neal J. Cohen and Howard Eichenbaum bring together converging findings from neuropsychology, neuroscience and cognitive science that provide the critical clues and constraints for developing a more comprehensive understanding of memory. Specifically, they offer a cognitive neuroscience theory of memory that accounts for the nature of memory impairment exhibited in human amnesia and animal models of amnesia, that specifies the functional role played by the hippocampal system in memory, and that provides further understanding of the componential structure of memory. The authors' central thesis is that the hippocampal system mediates a capacity for declarative memory, the kind of memory that in humans supports conscious recollection and the explicit and flexible expression of memories. They argue that this capacity emerges from a representation of critical relations among items in memory, and that such a relational representation supports the ability to make inferences and generalizations from memory, and to manipulate and flexibly express memory in countless ways. In articulating such a description of the fundamental nature of declarative representation and of the mnemonic capabilities to which it gives rise, the authors' theory constitutes a major extension and elaboration of the earlier procedural-declarative account of memory. Support for this view is taken from a variety of experimental studies of amnesia in humans, non-human primates, and rodents. Additional support is drawn from observations concerning the neuroanatomy and neurophysiology of the hippocampal system. The data taken from divergent literatures are shown to converge on the cental theme of hippocampal involvement in declarative memory across species and across behavioural paradigms.
1,437 citations
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TL;DR: It is found that those who received aerobic training showed substantial improvements in performance on tasks requiring executive control compared with anaerobically trained subjects.
Abstract: In the ageing process, neural areas1,2 and cognitive processes3,4 do not degrade uniformly. Executive control processes and the prefrontal and frontal brain regions that support them show large and disproportionate changes with age. Studies of adult animals indicate that metabolic5 and neurochemical6 functions improve with aerobic fitness. We therefore investigated whether greater aerobic fitness in adults would result in selective improvements in executive control processes, such as planning, scheduling, inhibition and working memory. Over a period of six months, we studied 124 previously sedentary adults, 60 to 75 years old, who were randomly assigned to either aerobic (walking) or anaerobic (stretching and toning) exercise. We found that those who received aerobic training showed substantial improvements in performance on tasks requiring executive control compared with anaerobically trained subjects.
1,340 citations
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01 Jan 1988TL;DR: This book provides a clear and simple account of the key ideas and algorithms of reinforcement learning, which ranges from the history of the field's intellectual foundations to the most recent developments and applications.
Abstract: Reinforcement learning, one of the most active research areas in artificial intelligence, is a computational approach to learning whereby an agent tries to maximize the total amount of reward it receives when interacting with a complex, uncertain environment. In Reinforcement Learning, Richard Sutton and Andrew Barto provide a clear and simple account of the key ideas and algorithms of reinforcement learning. Their discussion ranges from the history of the field's intellectual foundations to the most recent developments and applications. The only necessary mathematical background is familiarity with elementary concepts of probability. The book is divided into three parts. Part I defines the reinforcement learning problem in terms of Markov decision processes. Part II provides basic solution methods: dynamic programming, Monte Carlo methods, and temporal-difference learning. Part III presents a unified view of the solution methods and incorporates artificial neural networks, eligibility traces, and planning; the two final chapters present case studies and consider the future of reinforcement learning.
37,989 citations
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TL;DR: It is proposed that cognitive control stems from the active maintenance of patterns of activity in the prefrontal cortex that represent goals and the means to achieve them, which provide bias signals to other brain structures whose net effect is to guide the flow of activity along neural pathways that establish the proper mappings between inputs, internal states, and outputs needed to perform a given task.
Abstract: ▪ Abstract The prefrontal cortex has long been suspected to play an important role in cognitive control, in the ability to orchestrate thought and action in accordance with internal goals. Its neural basis, however, has remained a mystery. Here, we propose that cognitive control stems from the active maintenance of patterns of activity in the prefrontal cortex that represent goals and the means to achieve them. They provide bias signals to other brain structures whose net effect is to guide the flow of activity along neural pathways that establish the proper mappings between inputs, internal states, and outputs needed to perform a given task. We review neurophysiological, neurobiological, neuroimaging, and computational studies that support this theory and discuss its implications as well as further issues to be addressed
10,943 citations
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9,362 citations
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TL;DR: The meaning of the terms "method" and "method bias" are explored and whether method biases influence all measures equally are examined, and the evidence of the effects that method biases have on individual measures and on the covariation between different constructs is reviewed.
Abstract: Despite the concern that has been expressed about potential method biases, and the pervasiveness of research settings with the potential to produce them, there is disagreement about whether they really are a problem for researchers in the behavioral sciences. Therefore, the purpose of this review is to explore the current state of knowledge about method biases. First, we explore the meaning of the terms “method” and “method bias” and then we examine whether method biases influence all measures equally. Next, we review the evidence of the effects that method biases have on individual measures and on the covariation between different constructs. Following this, we evaluate the procedural and statistical remedies that have been used to control method biases and provide recommendations for minimizing method bias.
8,719 citations
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TL;DR: In this paper, a randomized clinical trial was conducted to evaluate the effect of preterax and Diamicron Modified Release Controlled Evaluation (MDE) on the risk of stroke.
Abstract: ABI
: ankle–brachial index
ACCORD
: Action to Control Cardiovascular Risk in Diabetes
ADVANCE
: Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation
AGREE
: Appraisal of Guidelines Research and Evaluation
AHA
: American Heart Association
apoA1
: apolipoprotein A1
apoB
: apolipoprotein B
CABG
: coronary artery bypass graft surgery
CARDS
: Collaborative AtoRvastatin Diabetes Study
CCNAP
: Council on Cardiovascular Nursing and Allied Professions
CHARISMA
: Clopidogrel for High Athero-thrombotic Risk and Ischemic Stabilisation, Management, and Avoidance
CHD
: coronary heart disease
CKD
: chronic kidney disease
COMMIT
: Clopidogrel and Metoprolol in Myocardial Infarction Trial
CRP
: C-reactive protein
CURE
: Clopidogrel in Unstable Angina to Prevent Recurrent Events
CVD
: cardiovascular disease
DALYs
: disability-adjusted life years
DBP
: diastolic blood pressure
DCCT
: Diabetes Control and Complications Trial
ED
: erectile dysfunction
eGFR
: estimated glomerular filtration rate
EHN
: European Heart Network
EPIC
: European Prospective Investigation into Cancer and Nutrition
EUROASPIRE
: European Action on Secondary and Primary Prevention through Intervention to Reduce Events
GFR
: glomerular filtration rate
GOSPEL
: Global Secondary Prevention Strategies to Limit Event Recurrence After MI
GRADE
: Grading of Recommendations Assessment, Development and Evaluation
HbA1c
: glycated haemoglobin
HDL
: high-density lipoprotein
HF-ACTION
: Heart Failure and A Controlled Trial Investigating Outcomes of Exercise TraiNing
HOT
: Hypertension Optimal Treatment Study
HPS
: Heart Protection Study
HR
: hazard ratio
hsCRP
: high-sensitivity C-reactive protein
HYVET
: Hypertension in the Very Elderly Trial
ICD
: International Classification of Diseases
IMT
: intima-media thickness
INVEST
: International Verapamil SR/Trandolapril
JTF
: Joint Task Force
LDL
: low-density lipoprotein
Lp(a)
: lipoprotein(a)
LpPLA2
: lipoprotein-associated phospholipase 2
LVH
: left ventricular hypertrophy
MATCH
: Management of Atherothrombosis with Clopidogrel in High-risk Patients with Recent Transient Ischaemic Attack or Ischaemic Stroke
MDRD
: Modification of Diet in Renal Disease
MET
: metabolic equivalent
MONICA
: Multinational MONItoring of trends and determinants in CArdiovascular disease
NICE
: National Institute of Health and Clinical Excellence
NRT
: nicotine replacement therapy
NSTEMI
: non-ST elevation myocardial infarction
ONTARGET
: Ongoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial
OSA
: obstructive sleep apnoea
PAD
: peripheral artery disease
PCI
: percutaneous coronary intervention
PROactive
: Prospective Pioglitazone Clinical Trial in Macrovascular Events
PWV
: pulse wave velocity
QOF
: Quality and Outcomes Framework
RCT
: randomized clinical trial
RR
: relative risk
SBP
: systolic blood pressure
SCORE
: Systematic Coronary Risk Evaluation Project
SEARCH
: Study of the Effectiveness of Additional Reductions in Cholesterol and
SHEP
: Systolic Hypertension in the Elderly Program
STEMI
: ST-elevation myocardial infarction
SU.FOL.OM3
: SUpplementation with FOlate, vitamin B6 and B12 and/or OMega-3 fatty acids
Syst-Eur
: Systolic Hypertension in Europe
TNT
: Treating to New Targets
UKPDS
: United Kingdom Prospective Diabetes Study
VADT
: Veterans Affairs Diabetes Trial
VALUE
: Valsartan Antihypertensive Long-term Use
VITATOPS
: VITAmins TO Prevent Stroke
VLDL
: very low-density lipoprotein
WHO
: World Health Organization
### 1.1 Introduction
Atherosclerotic cardiovascular disease (CVD) is a chronic disorder developing insidiously throughout life and usually progressing to an advanced stage by the time symptoms occur. It remains the major cause of premature death in Europe, even though CVD mortality has …
7,482 citations