Another Apology

I apologize to readers for going nearly a month without a post.  I've been unusually busy.  I will try to post more often now.

Thank you for your patience.

Thoughts on Why Younger Men and Older Women Sometimes Mate

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It is cliche to note that men are often attracted to younger women, and women to older men.  The typical evolutionary explanation(page 9) is that men generally prefer younger women, because the latter are more fertile on average.  Women usually prefer older men, because the men can command more resources on average, including experience, among other factors.

In recent years however, the phenomenon of the mutual attraction of younger men and older women is gaining attention.  Older women, roughly referring to women aged 35 or older, are popularly referred to as "cougars," while the men who share a mutual attraction are referred to as "cubs."

While a few recent demographic trends may provide some insight into the higher frequency of this relationship pattern, there are some purer evolutionary explanations as well.

When it comes to why older women may sometimes choose younger men, the former may find fewer mating opportunities with preferred older men(page 6, last 2 paragraphs), and hence settle for younger.  But, why would younger men find older women attractive?

Perhaps the reason is the same as that above for women sometimes dating younger men.  It could be due to a lack of younger mate availabity.   However, there may be an additional dimension to the attractiveness of older women to men, at least when the women look younger than their age.  Perhaps these women send signals of genetically-determined longer fertility lives, and hence represent an optimal mating strategy even in absence of a scarcity of younger or same-aged women. 

Of course, that last point is mere speculation, as I haven't found any research support for it yet.  If any of you find some, please let me know.

Horrible Reporting

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Here is a nice, quick post I can offer.  It's in reference to a report that appeared last month in Science Daily.  The report tries to make novelty out of a conclusion that deliberate and unconscious memory retrieval are facilitated by different pathways in the brain.  Well, how could it be otherwise?

The report goes on to claim that the processes involved in unconsciously retrieving memories and likewise forgetting them are mysteries.  This is simply untrue, except for purely neurophysiological mechanisms, though many of these are known too.  To quote here:

Science still does not fully understand why our brain sometimes automatically supplies us with a memory that we have done nothing to deliberately call to mind, whereas why, on other occasions, we cannot remember things even though we make efforts to recall them.

There are several memory systems in the brain, but the two major ones are the explicit and implicit.  The former is responsible for conscious, deliberate recall and the latter for unconscious recall.  The explicit allows attempts to connect with previously stored predictive contexts for sought (net rewarding)memories.  This is facilitated by the elicitation of incomplete predictive contexts, triggered consciously and unconscously.  There are no memories without contexts, so explicit memories require these partial predictive contexts and then use associational methods, including those involving metacognition, to try to connect with the more complete contexts.  The explicit system is involved to the degree that a context is new, so there is incomplete generalization.  Thus, this process only works some of the time. 

The implicit system involves well-learned habits that require little awareness.  Examples include motor learning, but can occur with any type of behavior strongly generalized across predictive contexts.

Even considering the normally awful media reporting of scientific work, this example stands out.  And this is worse for a publication that solely reports on science.

Posts in Progress

I apologize for going nearly a week-and-a-half without a post, but I've been very busy and working on some posts that are taking longer than anticipated.

For example, I'm considering whether antisocial behavior(sociopathic) can result from extreme depression, and how to formalize such a relationship.

I am also considering cases in which general intelligence, defined as relatively high stimulus processing rates, can make for less intelligent decisions.

Another post in progress is one on the attractiveness of older women to younger men.

And, there is consideration of the reason bullying occurs among children.

So, please have patience as I try to put as much quality into my posts as possible.

Yes, maybe I'm spreading my attention too thin by simultaneously working on so many posts, but I've been shifting toward topics that I've incorrectly thought would take less time to complete.

Artificial Emotions

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This article in New Scientist has me thinking about how to endow artificially intelligent machines with emotions.  This shouldn't be a hard task.

Referring to a previous post on mood, as well as one on emotions, a computerized machine can be fitted with sensors to facilitate machine learning, with unconditioned and conditioned stimuli as incentives.  Reward would be determined by the required rate intake of resources, and the net intake of resources deemed available.  Resources can include energy, and even social approval.  In the latter case, machines can detect facial features and be programmed to associate them with social signals, such as those revealed by facial expressions, for example.  The sum of all available  resources can be operationalized as mood.

The machine is then capable of attaching values to various stimuli and now emotions can be added.  Anger, for example, can be programmed as an unexpected subjective loss.  But could machines feel?

I think emotional feelings in human beings serve as signals to the working memory in the prefrontal cortex, allowing for metacognitive differentiation.  That is, with regard to our thinking about our emotional reactions, it helps to be able to distinguish each emotional response from others.  Hence, there is no reason to think such differentiation cannot be programmed into artificial intellgence systems.

Free Will Absolution?

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This book review has spurred me to offer a brief follow up to a previous post on free will.

 I agree with the review author Holly Anderson,  who dismisses the idea that "emergence," or the consideration that brain functioning as a whole is more than the sum of its parts, by pointing out that any process governed by the brain is deterministic. However, focus of this post is on the issue of whether this means people shouldn't be held responsible for their actions.

The answer, in my opinion, is that in a pure abstract moral sense they can't be, but we have to assign responsibility to those who engage in externally damaging behavior anyway, for practical reasons.  We have to protect society. 

By the way, it is interesting to me that the question of whether a lack free will cancels moral responsibility is only considered with respect to negative behavior, at least in my experience.

Suicide is Adaptive(Evolutionarily)

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Update:  This post is not meant to advocate suicide.  It only speaks to evoluationary motives.

Suicide is often a natural behavior.  This is because it may help to pass genes. 

This seeming paradox is resolved when you consider the implications of inclusive fitness, or more specifically with regard to kinship selection.  This refers to the fact that close relatives have a high number of genes in common, the hence the passing on of shared genes sometimes benefits from sacrifices at the expense of one or more relatives, even leading to death.  Particularly, individuals with low access to resources needed to pass genes directly, relative to family members, become a drag on the resources of others in the family.

This idea was perhaps first put forth by Denys deCatanzaro, but the logic first appealed to me years before I found this paper and related research. 

This is not to say that all cases of suicide are related to kinship selection, but does suggest the existence of a sort of "mental program" that is activated by low moods, relative to family members.  Other causes for suicide include the metacognitive avoidance of psychical and or physical pain, the influence of psychoactive drugs, and more purely neurological causes.

6 Days and No Longer Counting

I apologize for my lack of posts over the last six days.  Everyday, I've been busier than anticipated, always thinking that finishing one or more posts I've been working on was coming the very next day or night.  Hence, I didn't post a message revealing any intention to take a break from posting.

Unfortunately, my posts sometimes take hours to complete, given the research requirements.  Sometimes searching for and/or actually obtaining relevant papers create unanticipated delays, apart from unexpected changes in my general schedule. 

I will try to post more frequently whatever my schedule, but let you know when I'm not certain about the length of a delay.  Thank you for sticking with me.

Depressed Parents Play Favorites

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The model of behavioral investment as determined by mood that I previously presented has an interesting implication for the way parents treat their children.  That is, depressed parents are more likely to succumb to favoritism.  Specifically, as mood decreases, parental investment shifts toward children deemed more reproductively fit(1).

Parental investment involves the amount of time, energy, and other resources offered each child by their parents(2), and reproductive fitness(3) can be revealed in signals related to physical attractiveness(cuteness, etc), physical fitness, intelligence, emotional robustness, susceptibility to illness, ability to make friends, and even resemblance to one or both parents, among other cues.  There is even evidence that birth weight is moderated by a mother's stress levels(lower mood), with higher stress associated with lower weights.

This is part of a larger phenomenon(first link above) in which depressed parents often unconsciously develop high quantity, low parental investment reproductive strategies in environments peceived as hostile to higher per-child investment strategies. 


1. D. Beaulieu, D. Bugental (July 2008)  Contingent parental investment: an evolutionary framework for understanding early interaction between mothers and children.
Evolution and Human Behavior, Volume 29, Issue 4, Pages 249-255

2. Trivers, R.L. (1972). Parental investment and sexual selection. In B. Campbell (Ed.), Sexual selection and the descent of man, 1871-1971 (pp. 136-179). Chicago, IL: Aldine.

3. Hamilton, W.D. 1964. The genetical evolution of social behavior. Journal of Theoretical Biology 7:1-52

No Allergies or Immunity to Learning

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This post can be considered an extension of my last one on learned tolerance to addictive substances. 

Like reactions to addictive substances, allergic and immune responses are influenced by external environments and mental states.  Both can be learned and forgotten, depending on the contexts.  I lump them together here, because they are actually both functions of the immune system.

Both types of responses can be triggered by external environments and mental states that are similar to those in which allergens(former) or pathogens(for example, latter) were previously encountered.  Likewise, learned responses can fail to occur in environments and or mental states that are subjectively dissimilar.  So, when it comes to the acquisition and extinction(unlearning) of allergies and specific immune responses, all of the principles of learning apply.

One implication is that exposure treatments, involving the gradual presentation of contexts(stimuli) previously experienced with an allergen or pathogen, sans those threats, should sometimes diminish learned allergic and immune responses.  This is similar to systematic desensitization treatments used to treat phobias and more general anxiety disorders.  Perhaps this approach can also apply to treatment for some cases of autoimmune disorders.

So, this is just another example of how psychology can touch upon elements of the functioning of our bodies in what may be unexpected ways for many.