Amygdala-hippocampus dynamic interaction in relation to memory

Typically the term “memory” refers to the ability to consciously remember past experiences or previously learned information. This kind of memory is considered to be dependent upon the hippocampal system. However, our emotional state seems to considerably affect the way in which we retain information and the accuracy with which the retention occurs. The amygdala is the most notably involved brain structure in emotional responses and the formation of emotional memories. In this review we describe a system, composed of the amygdala and the hippocampus, that acts synergistically to form long-term memories of significantly emotional events. These brain structures are activated following an emotional event and cross-talk with each other in the process of consolidation. This dual activation of the amygdala and the hippocampus and the dynamics between them may be what gives emotionally based memories their uniqueness.

Indelibility SubCortical Emotional Memories

Acquisition and extinction of fear responses conditioned to a visual stimulus were examined in rats with ablations of visual cortex. Visual cortex lesions did not interfere with acquisition, indicating that visual fear conditioning, like auditory fear conditioning, is mediated by sub-cortical, probably thalamo-amygdala, sensory pathways. In contrast to acquisition, extinction was greatly prolonged, if not prevented, by cortical ablation. This resistance to extinction of sub cortical emotional memories may explain certain aspects of emotional memory in man.

Closed-loop brain training: The science of neurofeedback

Neurofeedback is a psychophysiological procedure in which online feedback of neural activation is provided to the participant for the purpose of self-regulation. Learning control over specific neural substrates has been shown to change specific behaviours. As a progenitor of brain–machine interfaces, neurofeedback has provided a novel way to investigate brain function and neuroplasticity. In this Review, we examine the mechanisms underlying neurofeedback, which have started to be uncovered. We also discuss how neurofeedback is being used in novel experimental and clinical paradigms from a multidisciplinary perspective, encompassing neuroscientific, neuroengineering and learning-science viewpoints.

Neuroception: A Subconscious System for Detecting Threats and Safety

The author describes recent findings on the neurobiological mechanisms involved in perceptions of risk and safety. The term “Neuroception” describes how neural circuits distinguish whether situations or people are safe, dangerous, or life threatening. Neuroception explains why a baby coos at a caregiver but cries at a stranger, or why a toddler enjoys a parent’s embrace but views a hug from a stranger as an assault. The author explains the Polyvagal Theory, which posits that mammals–especially primates–have evolved brain structures that regulate both social and defensive behaviors. The Polyvagal Theory describes three developmental stages of a mammal’s autonomic nervous system: immobilization, mobilization, and social communication or social engagement. A neuroception of safety is necessary before social engagement behaviors can occur. Infants, young children, and adults need appropriate social engagement strategies in order to form positive attachments and social bonds. Faulty neuroception might lie at the root of several psychiatric disorders, including autism, schizophrenia, anxiety disorders, depression, and Reactive Attachment Disorder.

Science and Sanity: An Introduction to Non-Aristotelian Systems and General Semantics

Selections from Science and Sanity represents Alfred Korzybski’s authorized abridgement of his magnum opus, Science and Sanity: An Introduction to Non-Aristotelian Systems and General Semantics. This second edition, published in response to the recent Korzybski revival, adds new introductory material and a revised index, providing an accessible introduction to Korzybski’s arguments concerning the need for a non-Aristotelian approach to knowledge, thought, perception, and language, to coincide with our non-Newtonian physics and non-Euclidean geometries, to Korzybski’s practical philosophy, applied psychology, pragmatics of human communication, and educational program. Selections from Science and Sanity serves as an excellent introduction to general semantics as a system intended to aid the individual’s adjustment to reality, enhance intellectual and creative activities, and alleviate the many social ills that have plagued humanity throughout our history.

Language in Thought and Action

Renowned professor and former U.S. Senator S. I. Hayakawa discusses the role of language in human life, the many functions of language, and how language – sometimes without our knowing – shapes our thinking in this engaging and highly respected book. Provocative and erudite, it examines the relationship between language and racial and religious prejudice; the nature and dangers of advertising from a linguistic point of view; and, in an additional chapter called The Empty Eye, the content, form, and hidden message of television, from situation comedies to news coverage to political advertising.

Bodily Changes in Pain, Hunger, Fear and Rage: An Account of Recent Researches Into the Function of Emotional Excitement

Cannon is best known for his work on the “Fight or Flight” response. In 1915, he coined the term “fight or flight” to describe an animal’s response to threats in “Bodily Changes in Pain, Hunger, Fear and Rage: An Account of Recent Researches into the Function of Emotional Excitement.” He is also credited with being one of the first to understand the significance of “Homeostasis” in the self-regulation of each human being. He developed the concept of “Homeostasis” from the earlier idea of Claude Bernard of milieu interieur, and popularized it in his book “The Wisdom of the Body” in 1932. Cannon presented four tentative propositions to describe the general features of homeostasis:

Constancy in an open system, such as our bodies represent, requires mechanisms that act to maintain this constancy. Cannon based this proposition on insights into the ways by which steady states such as glucose concentrations, body temperature and acid-base balance were regulated.

Steady-state conditions require that any tendency toward change automatically meets with factors that resist change. An increase in blood sugar results in thirst as the body attempts to dilute the concentration of sugar in the extracellular fluid.

The regulating system that determines the homeostatic state consists of a number of cooperating mechanisms acting simultaneously or successively. Blood sugar is regulated by insulin and other hormones that control its release from the liver or its uptake by the tissues.

Homeostasis does not occur by chance, but is the result of organized self-government.