Depression, Dreaming and Rehearsal learning

We all know that depression is marked by an increase in REM Sleep or dreaming and their are various theories of why this increased dreaming may be a root cause of depression itself. One theory posits that having too much dreams or emotional negativity even while sleeping (most dreams have negative content) may lead to maintenance of downward spiral of depressive cognitive and emotional style. Another theory posits that having too much negative dreams may lead us to get exhausted and the morning weariness found in depression is due to this fact.



I'll not comment regarding the purported mechanism and causal direction of link between depression and dreaming. Suffice it to note few pertinent facts:

• Depressives dream 3 -4 times more than normal people.
• Most Anti-depressants cause REM sleep to be suppressed and this may underlie their therapeutic action or may just be a side-effect.
• There is mixed evidence as to whether REM sleep is also altered in Mania (although a decrease in REM sleep is not mentioned in literature- if anything REM increases just like in depression)

Now I'll like to highlight an important experiment conducted by Wisconsin Madison scientists. They deprived rats of REM sleep and found that such rats became idiots in terms of survival sense and failed all standard test of survival. I'll first describe the procedure and their results and then theorize:

What happens when a rat stops dreaming? In 2004, researchers at the University of Wisconsin at Madison decided to find out. Their method was simple, if a bit devilish. Step 1: Strand a rat in a tub of water. In the center of this tiny sea, allot the creature its own little desert island in the form of an inverted flowerpot. The rat can swim around as much as it pleases, but come nightfall, if it wants any sleep, it has to clamber up and stretch itself across the flowerpot, its belly sagging over the drainage hole.

In this uncomfortable position, the rat is able to rest and eventually fall asleep. But as soon as the animal hits REM sleep, the muscular paralysis that accompanies this stage of vivid dreaming causes its body to slacken. The rat slips through the hole and gets dunked in the water. The surprised rat is then free to crawl back onto the pot, lick the drops off its paws, and go back to sleep—but it won't get any REM sleep.

Step 2: After several mostly dreamless nights, the creature is subjected to a virtual decathlon of physical ordeals designed to test its survival behaviors. Every rat is born with a set of instinctive reactions to threatening situations. These behaviors don't have to be learned; they're natural defenses—useful responses accrued over millennia of rat society.

The dream-deprived rats flubbed each of the tasks. When plopped down in a wide-open field, they did not scurry to the safety of a more sheltered area; instead, they recklessly wandered around exposed areas. When shocked, they paused briefly and then went about their business, rather than freezing in their tracks the way normal rats do. When confronted with a foreign object in their burrow, they did not bury it; instead, they groomed themselves. Had the animals been out in the wild, they would have made easy prey.

The surprise came during Step 3. Each rat was given amphetamines and tested again; nothing changed. If failure to be an effective rat were due to mere sleep deprivation, amphetamines would have reversed the effect. But that didn't happen. These rats weren't floundering because they were sleepy. Something else was going on—but what?

To me it seems that what is happening in these dream-deprived rats is an unlearning of learned helplessness paradigm. In learned helplessness, one stops exploring the environment and becomes extremely cautious. Learned helplessness is an extremely influential theory of depression and I have blogged about it previously. In the dream-deprived rats something exactly the opposite is happening - they are becoming more exploratory and sort of unlearning the basic survival instincts .

To me all this seems to nicely fit together. Dreams may be instrumental in rehearsal learning and when the rat (or human) has been repeatedly exposed to inescapable shocks (unavoidable stress), then it may lose the desire to explore not only in the real world, but also in the dream world - the primary purpose of which is to generate alternative strategies to previously un-encountered negative situations. When one loses or fails to find creative solutions to the inescapable situations, one falls in a negative dream loop whereby one fails to explore adequately new strategies or to reassess the environment in light of new evidences. Instead as one has failed to find creative solutions earlier, one;s dreams become pre-occupied with failure- and with each failure prompts more vigorous search for answers in the dream -thus leading to more REM sleep. Also, as REM sleep is required for thus maintaining the new (unhealthy) associations hence as long as adequate REM sleep is available one stays stuck with the learned negative associations and the learned helplessness.

SSRIs and other anti-depressants , by blocking the REM sleep , may be providing one additional step whereby dreaming stops for some duration and the synapses that underlie negative associations (that were constantly strengthened during dreams) are given time to naturally become weak. Thus events no longer have automatic negative connotations, but can be appraised afresh with a new outlook. This may be one putative mechanism of how anti-depressants work. This may also explain why anti-depressants take so much time to become effective. When dreaming stops, the unlearning doesn't happen in a day- the weakening of associations would take weeks and months to materialize and have an effect.

Cognitive - behavioral theory may also be working on the level of dreams and it would be interesting to note how much dreaming is reduced and brought to normal levels as CBT starts showing effects.


The behavior of the dream deprived rat seems almost manic- unconcerned with survival and unnecessarily risk-taking. One experiment that can be conducted is to first induce learned helplessness in rats (by exposing them to unavoidable shocks) and then dream-deprive them as per the above methodology. If dream-deprivation restores the normalcy in rats and removes the depressive symptomatology we have a new theory of how depression works. This is not a difficult experiment to do and can be easily performed. I'm sure it will lead to positive results. I look forward to hearing from some readers of this blog as to how the experiment actually went (I myself am in no position to conduct such experiments). Do let me know via comments the experimental results- even if they are negative.

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Depression not only has bland taste but bland sense of smell too

In one of my earlier post on depression, I had commented on the fact that those suffering from depression have less sensitivity to sweet and bitter tastes and as such may compensate by eating more sugar thus leading to the well documented diabetes - depression linkage.

In a new study it has just been discovered that not only depressives have bland sense of taste, their sense of smell is also diminished and they may make compensations by using greater amounts of perfume. Overall it seems that those suffering from depression will have bland subjective experience of flavor(which is a combination of both smell and taste) and thus may even not really find what they eat to be tasty.

To me, this is an important finding. To my knowledge no research has been done in other sense modalities (like vision), but there is every reason to think that we may discover a bland sense of vision in depression. Why do I surmise so? this is because there is extensive literature available regarding the manic state and how things seem 'vivid' during that state including visual vividness. If depression is the converse of Mania, it follows that a corresponding blandness of vision should also be observed in those who are clinically depressed.

We also know that in extreme or psychotic forms of Mania, auditory hallucinations may arise. I am not suggesting that hallucinations are equal to vividness, but I would definitely love to see studies determining whether the auditory sense is heightened in Mania (maybe more absolute pitch perception in Mania) and a corresponding loss of auditory absolute pitch perception in depression. If so found, it may happen that music literally becomes subdued for people with depression and they sort of do not hear the music present in everyday life!

Whether other sense like touch, vestibular/ kinesthetic , proprioception (a heightened sense of which may give rise to eerie out-pf-body experiences in Mania) are also diminished in depression is another area where research may be fruitful.

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pretend play = creating new worlds?

Edge asks a question each year to prominent scientists and there question this year was "What have you changed your mind about and why?". Well, they didn't invite me to answer that question (not yet :-) , so I wont force my thoughts on the readers of this blog; but instead would like to highlight one of the answers (by Alison Gopnik).

She mentions that she though earlier that pretend play (and related to that the adult fiction reading/creation) was a spandrel and had no evolutionary significance. Now she thinks that the capacity for pretend play is necessary for imagination to develop whcih is necessary for creating new worlds. I, to say the least, am firmly entrenched in the view that treats pretend play as of fundamental importance to development and it is heartening to get support from a prominent psychologist.

I reproduce below the response of Alison in its entirety. (emphasis added by me)

Imagination is Real

Recently, I've had to change my mind about the very nature of knowledge because of an obvious, but extremely weird fact about children - they pretend all the time. Walk into any preschool and you'll be surrounded by small princesses and superheroes in overalls - three-year-olds literally spend more waking hours in imaginary worlds than in the real one. Why? Learning about the real world has obvious evolutionary advantages and kids do it better than anyone else. But why spend so much time thinking about wildly, flagrantly unreal worlds? The mystery about pretend play is connected to a mystery about adult humans - especially vivid for an English professor's daughter like me. Why do we love obviously false plays and novels and movies?

The greatest success of cognitive science has been our account of the visual system. There's a world out there sending information to our eyes, and our brains are beautifully designed to recover the nature of that world from that information. I've always thought that science, and children's learning, worked the same way. Fundamental capacities for causal inference and learning let scientists, and children, get an accurate picture of the world around them - a theory. Cognition was the way we got the world into our minds.

But fiction doesn't fit that picture - its easy to see why we want the truth but why do we work so hard telling lies? I thought that kids' pretend play, and grown-up fiction, must be a sort of spandrel, a side-effect of some other more functional ability. I said as much in a review in Science and got floods of e-mail back from distinguished novel-reading scientists. They were all sure fiction was a Good Thing - me too, of course, - but didn't seem any closer than I was to figuring out why.

So the anomaly of pretend play has been bugging me all this time. But finally, trying to figure it out has made me change my mind about the very nature of cognition itself.

I still think that we're designed to find out about the world, but that's not our most important gift. For human beings the really important evolutionary advantage is our ability to create new worlds. Look around the room you're sitting in. Every object in that room - the right angle table, the book, the paper, the computer screen, the ceramic cup was once imaginary. Not a thing in the room existed in the pleistocene. Every one of them started out as an imaginary fantasy in someone's mind. And that's even more true of people - all the things I am, a scientist, a philosopher, an atheist, a feminist, all those kinds of people started out as imaginary ideas too. I'm not making some relativist post-modern point here, right now the computer and the cup and the scientist and the feminist are as real as anything can be. But that's just what our human minds do best - take the imaginary and make it real. I think now that cognition is also a way we impose our minds on the world.

In fact, I think now that the two abilities - finding the truth about the world and creating new worlds-are two sides of the same coins. Theories, in science or childhood, don't just tell us what's true - they tell us what's possible, and they tell us how to get to those possibilities from where we are now. When children learn and when they pretend they use their knowledge of the world to create new possibilities. So do we whether we are doing science or writing novels. I don't think anymore that Science and Fiction are just both Good Things that complement each other. I think they are, quite literally, the same thing.

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Perosnality vs situation: Mischel's cognitive person variables

I have covered a lot of personality theories , especially I am enamored by the developmental stage theories (like that of piaget/ erikson/ freud/ loveinger/ big five), but I have also linked to many relevant posts from the situationist blog and am only too aware of the power of situations.

The first person however , who took arms against the prevailing emphasis on personality and introduced the all important concept of situation in the picture was Walter Mishcel. though , he is most well known for this and his work on delay of gratification in children, he has also given an alternative to traits that we could use while assessing personality. these are the social and cognitive person variables that distinguish one person from other. It is interesting to note that these person variables too form a hierarchy and I suspect that they also follow a developmental pattern.

The five social and cognitive learning person variables Mischel uses are:

1. Competencies: skills, problem-solving strategies, concepts about the world, based on experiences; allows for successful adaptation; Cattell’s fluid intelligence; tools for “doing commerce” with the world; one’s capabilities.
2. Encoding strategies and personal constructs: attentional strategies and individual schemas: what you pay attention to, and what meaning you attach to the stimulus to attend to; categorization is a personal construct that allows one to understand the world; subjective interpretation; provides some consistency in the person’s behavior, although capable on being changed, which accounts for inconsistencies in behavior. One’s interpretations
3. Expectancies: behavior outcome expectancies: if I do this, then I can expect that; expectancies will be based on past experiences with similar situations; sometimes specific information is available that can create or change expectancies. If one’s can’t change expectancies when given new specific information, then Mischel considered the person maladaptive. The maladaptive individual is acting in accord with expectancies that do not represent the actual behavior-outcome rules in that particular situation. A second kind of expectancy relates to our confidence in our ability to perform competently, called self-efficacy. Our perceived self-efficacy is related to our capacity to do what needs to be done. A third kind of expectancy relates to the stimulus-outcome association: if this happens, I can expect this to follow.
4. Subjective values: one’s personal values are a variable in one’s decision to behave in a certain way. They are essentially the reinforcers for one's behavior
5. Self-regulatory systems and plans: behaviors depend on intrinsic reinforcement or punishment, based on our own performance standards. Future goals are made and plans are then compatible with these goals. We are teleological and purposeful in our behaviors.

To me this follows the five stage model. We first develop competencies , so that we can produce a range of behavioral outcomes. We then acquire knowledge using personal constructs and encoding schema's, and this is done idiosyncratically and subjectively to assess a situation. In the third step, we match situation (stimulus expectancy) and our behavior expectancies (self-efficacy expectancies) to predict how we should behave and what results we will get (outcome expectancies). In the fourth stage having assessed what outcome a behavior is likely to produce we analyze whether we subjectively value the outcome. The subjective valuation of outcome would still be guided by how others in our social circle have valuation for that outcome.In the final fifth stage, we put our individual spins on the outcome achievement by having things like intrinsic motivation and self-regulatory mechanisms. All this flows nicely and I strongly suspect that we develop a capacity to use a person variable only after a certain developmental phase is over.

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Ego Devlopment : the nine stages theory of Loevinger

As every reader of this blog knows I am hooked to developmental stage theories, so couldn't resist passing along this nine stage ego development theory of Loevinger. I will draw heavily from a course lecture by Prof. Kenneth Locke of Univ of Idaho, while describing the nine stage theory (prof Locke meanwhile clubs the 7th and 8th stage together into one, which I like and which takes the stages number to eight). Here you can find the full transcript of the lecture and here you can find the slides.


Before proceeding with the theory, let me tell you a bit about the method used by Loevinger. She used sentence completion paradigm where subjects had to complete sentences like

• My main problem is ...
• Being with other people ...
• The thing I like about myself is...

Here the responses provided were analyzed to find the process by which the ego made sense of experiences. I would request my readers to pause here and before proceeding to read the entire mail, complete these sentence stems in the comments below and let me offer them an analysis of which stage they are predominantly on. to give you an example of what you can fill, the first sentence " My main problem is ..." can be filled in many different ways like "...a slow internet connection", " ...the readability of this blog", " ...your thesis that seems too much steeped into stages mode of thinking" etc. do not worry too much about what you fill, juts go a=head and complete the sentences!!

Now lets get to the ego formation stages themselves:

The first stage is the pre-social and symbiotic stage. This is the stage that the ego is typically in during infancy. A baby has a very id-like ego that is very focused on gratifying immediate needs. They tend to be very attached to the primary caregiver, often the mother, and while they differentiate her from the rest of the world, they tend experience a cognitive confusion and emotional fusion between the caregiver and the self. But our understanding of this stage is more speculative than our understanding of other stages because pre-verbal infants we cannot use sentence completions and instead must rely on inferences based on observations.

The second stage is the impulsive stage. While this is the modal stage for toddlers, people can be in this stage for much longer, and in fact a small minority of people remain in this impulsive stage throughout their life. At this stage the ego continues to be focused on bodily feelings, basic impulses, and immediate needs. Not being particularly good at meeting these needs on their own, however, they are dependent and demanding. They are too immersed in the moment and in their own needs to think or care much about others; instead, they experience the world in egocentric terms, in terms of how things are affecting me. If something or someone meets my needs, it is good; if something or someone frustrates my needs, it is bad. Thus, their thinking is very simplistic and dichotomous.

The third stage is the self-protective stage. While this stage is particularly common in early and middle childhood, some individuals remain at this stage throughout their lives. The self-protective ego is more cognitively sophisticated than the impulsive ego, but they are still using their greater awareness of cause and effect, of rules and consequences, to get what they want from others. Therefore, they tend to be exploitive, manipulative, hedonistic, and opportunistic. Their goals is simply to “get what I want without getting caught”. Assuming others are like them, they are wary of what others want. They are also self-protective in the sense of externalizing blame--blaming others when anything goes wrong. Individuals who remain in the stage into adolescence and adulthood tend to, unless they are very smart, get into trouble; indeed, research using Loevinger’s sentence completion test shows that a high proportion of juvenile delinquents and inmates score at this self-protective stage.

The fourth stage is the conformist stage. We tend to see this stage emerging at the time Freud said the superego first emerges, around five or six, and is the most common stage later in elementary school and in junior high school. However, a number of people remain at this stage throughout their lives. Conformist individuals are very invested in belonging to and obtaining the approval of important reference groups, such as peer groups. They tend to view and evaluate themselves and others in terms of externals—how one looks, the music that you listen to, the words or slang that you use, the roles people assume to show what group they are in and their status within the group. They view themselves and others in terms of stereotypes—broad generalizations about what members of certain groups are or are not like. While from the outside such individuals may seem superficial or phony, they do not experience it that way because this group self is their real self. More generally, they tend to view the world in simple, conventional, rule-bound and moralistic ways. What is right and wrong is clear to them—namely, what their group thinks is right or wrong. Their feelings also tend to be simple and rule-governed, in the sense that there are some situations in which one feels happy, and other situations in which one feels sad. While Loevinger does try to avoid describing some stages as better than others, she does use the somewhat pejorative terms "banal" and “clichéd” to describe the conformist understanding of feelings. Interestingly, both feelings of happiness and feelings of shame tend to peak at this stage. Shame peaks because they are so concerned about approval from their group; consequently, the threat of shame is a powerful tool that groups can use to control individuals at this stage. On the other hand, as long as their place in the group is not threatened, conformist egos are quite happy, even happier than egos at the later stages, where right and wrong can never again be so simple and clear.

The fifth stage is the self-aware stage. This stage is the most common stage among adults in the United States. The self-aware ego shows an increased but still limited awareness deeper issues and the inner lives of themselves and others. The being to wonder what do I think as opposed to what my parents and peers think about such issues as God and religion, morality, mortality, love and relationships. They tend to not be at the point where they reach much resolution on these issues, but they are thinking about them. They are also more aware that they and others have unique feelings and motives, different from those that might be prescribed by the feeling rules they have learned from movies and books and other people. They recognize that just because one is part of the group does not mean that one always feels or thinks the same as the other group members and that’s true for other people in other groups as well. In short, they are appreciating themselves and others as unique. Increasing awareness of one’s unique feelings and motives creates tension between the “real me” and the “expected me”, which can lead to increased conflicts with family and peers. Finally, this ability to wonder whether your family or peers are right about what is right and wrong, to question whether you have been right about what is right and wrong, can lead to increased self-criticism.
At the sixth stage, the conscientious stage, this tendency towards self-evaluation and self-criticism continues. The conscientious ego values responsibility, achievement and the pursuit of high ideals and long-term goals. Morality is based on personally-evaluated principles, and behavior is guided by self-evaluated standards. Consequently, violating one’s standards induces guilt. This differs from the conformist stage where the tendency is to feel shame. Shame arises from not meeting the others’ expectations; guilt arises from not meeting one’s own expectations. Greater self-reflection leads to greater conceptual complexity; experiencing the self and the world in more complex ways; and this includes experiencing one’s own feelings and motives in more accurate and differentiated ways and expressing them in more unique and personal terms. Finally, with increasing awareness of the depth and uniqueness of others’ feelings and motives as well comes increasing concern with mutuality and empathy in relationships.

Before going on I should mention that the preceding three stages—the conformist, self-aware, and conscientious stages—are the most common for adults in the United States, and there are fewer and fewer people at the stages we are about to examine. Moreover, Loevinger suggested that we all have a hard time understanding stages that are more than one level above our own, so for many of us who are at the middle stages it can be hard to fully grasp the highest stages.

At the seventh stage, the individualistic stage, the focus on relationships increases, and although achievement is still valued, relationships tend to be more valued even more. The individualistic ego shows a broad-minded tolerance of and respect for the autonomy of both the self and others. But a wish gives others the autonomy to be who they really are can conflict with needs for connection and intimacy. The heightened sense of individuality and self-understanding can lead to vivid and unique ways of expressing the self as well as to an awareness of inner conflicts and personal paradoxes. But this is an incipient awareness of conflicting wishes and thoughts and feelings—for closeness and distance, for achievement and acceptance, and so on—but there is unlikely to yet be any resolution or integration of these inner conflicts.

At stage eight, the autonomous stage, there is increasing respect for one’s own and others’ autonomy. The autonomous ego cherishes individuality and uniqueness and self-actualization; individuals’ unique and unexpected paths are a source of joy. And these independent paths are no longer seen in opposition to depending on each other; rather relationships are appreciated as an interdependent system of mutual support; in other words, it takes a village to raise and sustain an autonomous ego. There is also greater tolerance of ambiguity. In particular, conflicts—both inner conflicts and conflicts between people—are appreciated as inevitable expressions of the fluid and multifaceted nature of people and of life in general; and accepted as such, they are more easier faced and coped with. Finally, the heightened and acute awareness of one’s own inner space is manifest in vivid ways of articulating feelings.

At the final stage, the integrated stage, the ego shows wisdom, broad empathy towards oneself and others, and a capacity to not just be aware inner conflicts like the individualistic ego or tolerate inner conflicts like the autonomous ego, but reconcile a number or inner conflicts and make peace with those issues that will remain unsolvable and those experiences that will remain unattainable. The integrated ego finally has a full sense of identity, of what it is, and at this stage it is seeking to understand and actualize my own potentials and to achieve integration of all those multi-faceted aspects of myself that have become increasing vivid as I’ve moved through the preceding three stages. In Loevinger’s research this highest stage is reached by less than 1% of adults in the United States.

Prof. Locke, does a good job of describing the stages, so I have juts copied the relevant sections from the transcript. Its however important to note the parallels here with other eight stage developmental theories. The first stage has to do with the differentiation of self from world and formation of ego in the first place. The second stage has to do with egocentric ego formation. The third with manipulative ego formation. The fourth with societal and conformist ego formation. The fifth stage with a self -aware or reflective ego formation. The sixth stage is qualitatively different and involves issues such as relationships with others and issues of intimacy and ego involved in relationships. The seventh and eighth stages have to do with interpersonal ego and the last with an integrative ego. All this follows the general developmental template and framework.

So don't forget to fill the sentences completion exercise and let me speculate on the ego stage of my readership!

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Developmental Stages: New Age concurs

I recently came across a series of article by Bill Harris, director of Centerpointe institute, regarding cognitive development and I found them relatively well-informed. Bill is a new Age Guru, but his articles were relatively well -informed regarding Piaget's developmental stages; moreover he shares my enthusiasm for developmental stages and believes in extending these stages beyond Piaget's four. The series is still incomplete and I link to the first two posts in the series.

I liked his linking these stages with the Jean Gebser's structure of consciousness and the consequent archaic, magical, mythical, mental and integral stages. I also liked his emphasis on perspective taking as an integral part of developmental process and I have covered that in detail here. However, he doesn't differentiate between the stages whereby one starts understanding that others have a different viewpoint/ perspective ( social-informational perspective) vis-a-vis when one starts adopting the viewpoint of another (self-reflective perspective). See my earlier post for more on these perspective stages as outlined by Robert Selman.

What I didn't like though, and found many issues with , was the various pathologies he associated with failures of developmental tasks at each stage. These he seemed to just pull out of his hat , with neither empirical support or strong theoretical foundations. Nevertheless, the series of articles may serve as a good refreshed for Piaget's theories of cognitive development for readers of this blog.

Some excerpts:

Cognitive development refers to our ability to perform various types of operations on what we encounter in the world and in our awareness. To live in the world, accomplish various things, and deal with the challenge of being human, we first learn to ”work with” (deal with, manage, get things done with) our body, then with objects, then with symbols, concepts, and ideas, and–if development continues to the highest transpersonal or transrational levels of development–we eventually add ways of dealing with life that are beyond the realm of ideas.

Sensorimotor, Piaget’s first stage (the stage before preoperational), is sometimes referred to as archaic in other naming conventions (in this case, in that of Jean Gebser).

Piaget divided cognitive development into four broad stages: 1) sensorimotor (0-2 years), 2) preoperational, or “preop” (2-7 years), concrete operational, or “conop” (7-11 years), and formal operational, or “formop” (11 years onward). Each of these can be divided into several substages. The ages are averages, and since a person could stop and remain at any level, you can find many adults at each level (though not many are found at the sensorimotor stage).

In this discussion I’ll also use some of the stage names used by Jean Gebser and Ken Wilber: archaic (similar to sensorimotor), magic (similar to early preoperational), magic-mythic (late preoperational), mythic (early concrete operational), mythic-rational (late concrete operational), and rational (formal operational). This is just to confuse you, of course.

In the sensorimotor stage, the infant uses senses and motor abilities to understand the world, beginning at first with reflexes and eventually using complex combinations of sensorimotor skills. At the beginning of this stage, the infant cannot yet distinguish itself from its environment (what some have called an experience of oceanic oneness). This has also been called a state of “primary narcissism,” because the infant is embedded in or undifferentiated from the environment.

I suggest, this should be enough to whet your appetite and that you go to the original source to get additional servings.

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Memory formed more easily in daytime

As per a new Nature Reviews Neuroscience research highlight , conditioning in zebrafish happened better during subjective daytime (SD) as compared to subjective nighttime (SN) and this effect was mediated by the release of Melatonin during nighttime. the authors conclude that Melatonin suppresses memory formation in Zebrafish.

Learning and memory are known to be influenced by the time of day, but the nature and mechanism of this modulation has been elusive. Now, a new study shows that melatonin, a hormone released in a circadian fashion, affects memory consolidation in zebrafish.

Melatonin release peaks during the night and falls during the day, and melatonin has been shown to affect neuronal firing in the hippocampus. The authors therefore decided to investigate whether melatonin mediates the effects of the circadian system on memory formation. They found that bathing the zebrafish in 50 M melatonin prior to SD conditioning significantly suppressed memory formation, whereas administration after conditioning or prior to testing had no effect. Furthermore, administration of a melatonin-receptor antagonist prior to SN conditioning significantly improved memory retention, as did removal of the pineal gland, the site of melatonin release.

Taken together, these results show that memory formation in zebrafish is inhibited during the night relative to the day, and that this modulation is mediated at least in part by circadian melatonin release. This might direct future research into improving mental performance in humans.

While extending the research results from zebrafish to humans may be premature, some simple studies with human subjects can confirm the effect of melatonin on human learning. and memory formation.

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The Five Core Social Motives

Susan Fiske in a popular needs model has identified Five Core Social Motives , easily remembered by the acronym BUC(k)ET standing for (Belonging, Understanding, Controlling, Enhancing Self, and Trusting) . In this system, belonging is the root need, the essential core social motive. The others are all said to be in service to, facilitating, or making possible effective functioning in social groups.

I now, give detailed descriptions of each motive based on Fiske's chapter in Motivated Social Perception book.

1. Belonging: People are motivated to affiliate and bond with each other.
2. Understanding: to belong , people are motivated to create an accurate-enough shared social understanding.
3. Controlling:People are motivated to feel competitive and effective in their dealings with the animate and inanimate environment.
4. Enhancing Self: Hoping that other will see you as socially worthy fits the core social motive of enhancing self.
5. Trusting:Viewing the world as benevolent enables people to participate in many group activities without undue suspicion or vigilance.

I also came across an interesting paper that discusses many need theories. They have this to say about Fiske's theory:

Based on a comprehensive literature review of a wide variety of writings on basic needs and motives, Stevens and Fiske (1995) argued that there was overall agreement on five basic needs. Fiske (2002; 2004) continued to develop and elaborate this set of basic needs, or core social motives, using the BUC(K)ET acronym as a mnemonic device for the five motives: Belonging, Understanding, Controlling, Enhancing Self, and Trusting (leaving the K for students to play with if they would like to imagine a sixth motive). In this system, belonging is the root need, the essential core social motive. The others are all said to be in service to, facilitating, or making possible effective functioning in social groups.

As implied by its name, this theory is specifically designed to apply to needs that arise in social settings. "Core Social Motives describe fundamental, underlying psychological processes that impel people’s thinking, feeling, and behaving in situations involving other people" (Fiske, 2004, p. 14). A basic assumption of this theory is that underlying all of the basic needs is an evolutionary process that has led to these characteristics of human nature because they promote survival of the individual through belonging in groups. Although this kind of imagined evolutionary, survival-oriented thinking is not logically a required aspect of a theory of basic needs with a root need structure, in fact such thinking has been employed in the development of all three of the root need theories.

I am compelled to chalk the five social motives in terms of the first five developmental tasks.

1. Belongingness. In the absence of bonding and affiliating with other people, one would not be able to acquire the feelings of trust necessary to operate smoothly in society.
2. Understanding: When people create accurate-enough shared social understanding they are not hounded by feelings of doubt and shame in relation to social relationships and society functioning.
3. Controlling: By feeling competitive and effective in dealing with one's animate and inanimate environment one can generate positive feelings of initiative in relation to social functioning and void any guilt over ineffectiveness.
4. Enhancing Self: If others see one as socially worthy, then this gives rise to feelings of industry.
5. Trusting: One needs a trusting environment to be able to brood over subtle questions like those of personal identity.

The core Social Motives seems to be a very promising theory that lets us analyse motives and needs at the social level of analysis . As such it deserves greater attention from the research community.

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