Monthly Archives: June 2015

A weird model

A while ago Tiny Buddha site had an article by Lisa Esile. I often like Tiny Buddha articles but not those of this sort: “7 Secrets Your Mind Doesn’t Want You to Know”. My reaction is to wonder what is the ‘you’ that does not include ‘your mind’. There is the type of dualism that we have been encountering for many years, since Descartes’ time, and then there is this other new kind of dualism. A ‘you’ have can know things but is not ‘your mind’ seems a crazy idea. What exactly is this ‘you’ thinking with?

The article starts with, “Our mind is inherently scared. That’s its job, to be cautious; to keep us alive, to have us cross roads safely, and not get eaten by a lion. But left unchecked, it can become paralyzed with fear and meaner than a cornered crocodile.” Who says that we are likely to be paralysed with fear or mean? What sort of mind is being envisaged here? So we are careful and do not endanger our lives but that does not make us paralysed or mean. The idea is that a power struggle between ourselves and our minds is going on, with ourselves having the better judgement. Apparently judgement is some magical gift that does not require a mind to produce it. “We feel anxious, fearful, sad, or resentful when we give our mind too much power, when we follow all of its dopey ideas against our better judgment.”

There is a hint to what she means by mind. “Your mind is smart. Not wise smart, but computer smart.

Your mind isn’t into all that woolly intuition jazz. It wants facts. It likes making calculations. Running the odds.” Perhaps she is calling ‘mind’ the conscious mind and ‘you’ the unconscious mind, although this is not a very accurate description of type 2 thought. I have a big problem with her idea in that I do not see two minds any more than I see a separate mind and you. I see one mind and it is aware of only part of its functioning through consciousness. And … it is that consciousness that gives us the concept of ‘self’.

Esile goes on to describe the various fights between two sets of ideas, one ascribed to ‘mind’ and the other to ‘self’. It is almost impossible to imagine having the disagreements described. They may be descriptions that ring true to others. But I cannot shake the idea that divided our sense of self into different compartments is not helpful; having those compartments oppose one another is positively unhealthy. We have a brain and it functions as a whole not as separate parts - one of its functions is ‘mind’ or thought/memory/action/awareness/volition/emotion – ‘mind’ includes the creation of a world and ourselves in that world and a partial awareness of this creation that we experience as consciousness – so we are self-aware of a model of the world and a model of ourselves. There is absolutely no reason or advantage in modelling ourselves as two entities, ‘mind’ and ‘self’, that carry on a power struggle. Rather than struggle and fight, we can learn to think and act in ways that satisfy us and add to our confidence and happiness. We don’t do this be giving ourselves orders but by asking ourselves ‘how’, ‘why’, ‘which way’ questions.

Counting crows

It is getting to be common knowledge that some birds can count. Recent research (citation below) has shown some of the details of how crows handle numbers. They have a different brain architecture from mammals but in some ways show similar functions to our neo-cortex in their endbrain association area. This points to possible convergent evolution.

Ditz and Nieder planted electrodes in the endbrain of crows and recorded activity of NLC (nidopallium caudolaterale) neurons. The birds were shown groups of items and the NCL neurons shown activity to specific numbers of items. The activity of a particular neuron peaked at a particular number.

Here is the abstract: “It is unknown whether anatomical specializations in the endbrains of different vertebrates determine the neuronal code to represent numerical quantity. Therefore, we recorded single-neuron activity from the endbrain of crows trained to judge the number of items in displays. Many neurons were tuned for numerosities irrespective of the physical appearance of the items, and their activity correlated with performance outcome. Comparison of both behavioral and neuronal representations of numerosity revealed that the data are best described by a logarithmically compressed scaling of numerical information, as postulated by the Weber–Fechner law. The behavioral and neuronal numerosity representations in the crow reflect surprisingly well those found in the primate association cortex. This finding suggests that distantly related vertebrates with independently developed endbrains adopted similar neuronal solutions to process quantity.

It is interesting, and confirms other bird studies, that:

  • they can put items in categories in order to count them,
  • they can make a set of the items in a particular category,
  • they can assess the quantity on a logarithmic scale (like 1, 2, 3, 4, 6ish, 9ish, 15ish etc),
  • this is an abstract quantity and does not depend on the arrangement, size etc. of the items.

Citation: Helen M. Ditz and Andreas Nieder. Neurons selective to the number of visual items in the corvid songbird endbrain. PNAS, June 2015 DOI: 10.1073/pnas.1504245112

 

The smell of the land

The sense of smell is intriguing. It is not as readily conscious as sight, hearing, touch and taste; so it is often discounted. However, humans do have the ability is smell quite well and can learn to do so in sophisticated and conscious ways. Perfumers are an example of this. We also know that a particular smell can bring back the memory of a place in a flash that seems quite miraculous. It is the most important sense for many mammals – used to identify objects and places, track and navigate, and communicate emotional signals. There is no reason to think that we are that much different; we probably use smell as a background (largely unconscious) canvas on which to perceive the world.

Recent research (citation below) has indicated such a canvas. Jacobs and others experimented with human subjects to see if they could map their surroundings using odour gradients. They used a large room with two distinct sources of different odours. The subjects were disoriented, placed in a spot and asked to remember its smell. They were disoriented again and asked to find the spot using their memory of the odour. This was done first with sight and hearing blocked and only the sense of smell available, then repeated with sight as the only sense available, and finally with all three senses blocked. The subjects could come close to the target spot with scent alone, compared to the control of none of the three senses being available.

This is a distinct ability and not the same a tracking a smell or identifying an object or place. This is the formation of a map based on odour gradients. Spatial maps are created in the hippocampus and the olfactory bulb is strongly connected to the hippocampus. The authors address the relationship between the odour map, the sound map (echo location), and the visual map etc. “The ability to navigate accurately is critical to survival for most species. Perhaps for this reason, it is a general property of navigation that locations are encoded redundantly, using multiple orientation mechanisms, often from multiple sensory systems. Encoding the location with independent systems is also necessary to correct and calibrate the accuracy of any one system. As a general principle, then, navigational accuracy and robustness should increase with the number of unique properties exhibited by redundant orientation systems.

Abstract: “Although predicted by theory, there is no direct evidence that an animal can define an arbitrary location in space as a coordinate location on an odor grid. Here we show that humans can do so. Using a spatial match-to-sample procedure, humans were led to a random location within a room diffused with two odors. After brief sampling and spatial disorientation, they had to return to this location. Over three conditions, participants had access to different sensory stimuli: olfactory only, visual only, and a final control condition with no olfactory, visual, or auditory stimuli. Humans located the target with higher accuracy in the olfaction-only condition than in the control condition and showed higher accuracy than chance. Thus a mechanism long proposed for the homing pigeon, the ability to define a location on a map constructed from chemical stimuli, may also be a navigational mechanism used by humans.”

Citation: Jacobs LF, Arter J, Cook A, Sulloway FJ (2015) Olfactory Orientation and Navigation in Humans. PLoS ONE 10(6): e0129387. Doi:10.1371/ journal.pone.0129387