Monday, 27 April 2015
The Impression of Déjà Vu.
This week we’d like to suggest some readings on a strange phenomenon that people may experience when travelling, among other occasions: the impression of déjà vu.
The first link below describes just one example of this phenomenon: you are touring a castle in a country that you are visiting for the first time, when suddenly you have the impression that you have been there before. But after the tour, while visiting the castle’s gift shop, you see a postcard with a photo of the castle, and you realize that a movie that you saw several years ago was shot there. The two experiences seemed too distant or disjointed in your memory for you to make the connection explicitly, but they were close enough for you to have an implicit sense of familiarity. (more…)
The Emergence of Consciousness | Comments Closed
Monday, 13 April 2015
Recent Studies on the Role of Sleep
As Evan Thompson, a philosopher of biology and the mind, stated in a recent lecture, our Western way of life is so focused on productivity as a dominant value that when we go to bed, we are so exhausted that we literally “crash” into sleep. As a result, we very often do not even experience the special state of consciousness known as hypnagogia, which normally occurs during the first phase of falling asleep. When someone is in this state, they are still sensitive to sensory inputs from the outside world, but no longer entirely awake, and they are more likely to make all sorts of original mental associations.
In addition to watching Thompson’s lecture (see first link below), you may want to read Waking, Dreaming Being (the book on which the lecture is based, published in 2014), or his earlier, very rewarding book, Mind in Life (2007). (more…)
Monday, 30 March 2015
Is There an Evolutionary Continuity between Spatial Navigation and Declarative Memory?
Sometimes someone comes up with a hypothesis whose parts fit together so neatly that it seems amazing that no one has ever thought of it before. A good example is the hypothesis proposed by György Buzsáki and Edvard Moser in the January 2013 issue of the journal Nature Neuroscience, where they propose that there is an evolutionary continuity between the cognitive processes that we use to orient ourselves in space and and the mechanisms that underlie our declarative memory. (more…)
Memory and the Brain | Comments Closed
Saturday, 14 March 2015
The “Coming Out” of the Electrical Synapse
The first living organisms composed of more than one cell first appeared on Earth slightly over 3 billion years ago. Once they did, the need arose for all of the cells in each organism to co-ordinate their efforts toward a single goal: the survival of the organism as a whole. To do so, these cells began secreting molecules that, by binding to the surface of other cells, informed them about what was happening elsewhere in the organism.
That, in short, is the origin not only of the human hormonal system but also of human synapses: the connections between nerve cells. In general, when people talk about synapses, they are referring to chemical synapses, into which neurotransmitters are released by the presynaptic neuron, then migrate across a space measured in nanometres to bind to receptors on the postsynaptic neuron on the other side.
But there is another category of synapses as well: electrical synapses. (more…)
From the Simple to the Complex | Comments Closed
Monday, 23 February 2015
How Posture Can Affect the Brain
For decades now, scientists have had a good knowledge of the descending neural and hormonal pathways by which the human brain influences the human body. But until quite recently, there was still a tendency to underestimate just how much the human body influences the human brain. In an experiment reported in 2010, however, social psychologist Amy Cuddy showed that simply adopting a body posture associated with dominance will, within two minutes, cause measurable changes in people’s blood concentrations of certain hormones, and in certain of their behaviours, such as risk-taking. (more…)
From Thought to Language | Comments Closed
