Darlene Forde's blog

Book Review: In Search of Memory: the emergence of a new science of the mind.
Eric R. Kandel. W. W. Norton, 2006.

After a semester of exploring the workings of the brain and the mind, what (and how) will you remember? In his book In search of memory: the emergence of the mind, Eric Kandel—2000 Nobel Prize winner in Physiology or Medicine for his work on signal transduction in the nervous system—presents a personal account of his lifelong attempt to understand the biological basis for memory set against a background of the development of modern cognitive neuroscience and the evolution of a new scientific paradigm. Kandel touches upon practically all of the topics explored this semester: the structure and function of neurons, how cells communicate via action potentials and neurotransmitter, the dynamic nature and multi-routed nature neuronal systems that incorporate both excitatory and inhibitory signals, how synaptic signals are strengthened. He also explores in greater detail the nature of short-term and long-term memory and the role that genes play with much more beside. Reminiscent of Watson’s Double Helix, In Search of Memory conveys a passion and excitement for scientific discovery; but where Watson’s 1968 work reflected his youthfulness, Kandel’s work demonstrates his sensitivity and maturity. Kandel’s familiarity with the key players and important contributions to his field of scientists and post-doctoral students is inspiring. We are presented with an almost Kuhninan intellectual account of the structure of the scientist revolution/evolution of neuroscience. We see how new ideas arise out of a mosaic of existing beliefs. Indeed, after reading Kandel’s five hundred page book, one gets the sense of seeing not merely the forest of memory and neurons, but also of the trees proteins and genes that play a role in the strengthening of synaptic connections.

In this course, I have become intrigued by cultural attempts to access and control the “unconscious” parts of the nervous system. Non-western cultures have established methods which allow (or purport to allow) untraditional connections to be made in the nervous system, methods which allow the practitioner to transcend ordinary levels of consciousness and reach higher states of consciousness (i.e. meditation, yoga, Buteyo, martial arts). On a physiological level, we can say that masters of these arts may possess the ability to make direct connections between the part of the neocortex we call the I-function and the autonomic division of the nervous system—the unconscious. These methods violate many of the neuronal networks and associations that we expect in the nervous system. For example, it is difficult for me to imagine that I might directly control the movements of my small intestine. How could a neuronal network be established that might run from my I-function to the motor neurons in my small intestine in the encouraging it to contract shortly after a meal? Whether the direction is direct—a neurons pathway leading directly from my neocortex to the motor neurons in the smooth muscle—or indirect—a neuronal path that takes a bridge between neighboring “counties” of the nervous system—is irrelevant as long as these pathways or roads can be maintained and utilized consistently and without difficulty.

It happens to all of us occasionally. As you walk down the hallway you see a familiar face—someone you have recently met—you reach into your brain expecting a complicated series of synaptic firing to bring forth the name person in front of you only to be disappointed. Although you know it is there in the recesses of your mind, you cannot summon the name of your new acquaintance. You settle instead for the ubiquitous nod and the word “hello”.

Where failure to occasionally recall the name of new acquaintance may feel uncomfortable, it typically does not create huge difficulties. For me this scenario happens all too often. Names of acquaintances and friends of less than a year’s duration frequently elude me at pivotal movements. Although my problem with name recall is worse for personal names, I also occasionally experience difficulties recalling the name of specific objects or “common names”. Indeed my friends and colleagues are familiar with me using the most round-about ways to identify specific people or objects. Physicians and psychologists have several clinical terms to describe this word-finding problem. Anomia is one general term for problems with word finding or recall that occurs with no impairment of comprehension or the capacity to repeat the words; the terms anomic and nominal aphasia are also used. (1)

Ask a random person walking down the street whether scents or odours can have an impact on behaviour and the answer will undoubtedly be yes. If the person had an interest in science they might even give you a concise explanation of the process. “When odour molecules are inhaled they pass up the nostrils until they arrive at a postage-stamp sized region known as the olfactory epithelium,” she might say. “Here the odor molecules are picked up my chemoreceptors, initiating action potentials, sending messages to the brain. Once recognized by the limbic system, this information is received, interpreted and possibly initiates a response,” she might conclude. (1)