Why Is Human Memory So Variable and Subjective?

I can mobilize an eidetic recall of the events at my last party in my apartment in New Orleans in May, 1969 (including the brew I was drinking), and yet a brother who visited me with a friend can't recall even being there. (I showed him the photos, and told him he was the one taking them.)  How is it I can recall this event including that he was there, in person, doing the photography, but he can't?

How is it that other events also may slip off the memory grid for him, and not for me, and in other cases slip off my memory grid but not his?  How is it my wife can exactly recall a movie we went to a year ago, but I can't? How is it I can recall exactly where my wife and I ate at Dallas-Ft. Worth airport in May, 2003 - while in transit to Barbados -but my wife can't?

All these questions and more occurred to me lately, and I began to inquire into why human memory is such a fragile, imperfect, subjective and variable thing. What we do know is that the hippocampus (named after its resemblance to the seahorse, from the Greek hippos meaning "horse" and kampos meaning "sea monster") plays important roles in the consolidation of information from short-term memory to long-term memory and spatial navigation. The hippocampus is located under the cerebral cortex . In primates it is located in the medial temporal lobe, underneath the cortical surface. It contains two main interlocking parts: Ammon's horn and and the dentate gyrus.

In Alzheimer's disease, the hippocampus is one of the first regions of the brain to suffer damage; memory loss and disorientation are included among the early symptoms. Damage to the hippocampus can also result from oxygen starvation (hypoxia), encephalitis, or medial temporal lobe epilepsy. People with extensive, bilateral hippocampal damage may experience anterograde amnesia—the inability to form or retain new memories.

In the case of Janice's cousin Desmond,  who died of Alzheimer's disease two years ago, the first memories lost were of distant events - while he retained memories of more recent ones. This is actually in contrast to how the disease usually presents, with long past events much more easily recalled than recent ones.


But let's leave out Alzheimer's and simply ask why memory varies so much in normal people, and how it is we differ so markedly in what events we can recall.  Some hints were presented in the Scientific American article 'The Language of the Brain' (October, 2012). What we learn is interesting to say the least.  This is in terms of "sequences of synchronized spikes"  in the particular cortical region to enable a critical factor in perception and memory.

As the article observes (p. 59):

"It appears that such synchrony acts to emphasize the importance of a particular perception or memory passing through conscious awareness."

In addition, evidently the degree to which we pay attention determines the frequency of the synchronized spikes in the 'gamma band' of frequencies (30 - 80 Hz).  The higher the frequency, the more numerous the synchronized spikes, the better a memory will be recalled. Further, gamma band signaling between distant cortical areas is also involved - as discovered by Pascal Fries of the Ernst Strugman Institute for Neuroscience.

Another interesting aspect of subjective memory I've found is that in places where I've actually lived over time I have much better memories of events than for the odd times I visit other locations - for relatively brief times. In the latter case, my memory is often patchy and unreliable. This is one reason whenever I travel now I keep a daily journal of events. In this way I can easily grab a journal kept over any past vacation, or brief interlude, and see what happened on such and such a day without having to play craps with my memory. (Which I admit is variable: excellent and eidetic in some realms and not so much in others!)

Research by Margarita Behrens of the Salk Institute - cited in the article - has also traced signal deficits to a neuronal cell called a "basket cell" - which is involved in synchronizing spikes in nearby circuits. An imbalance of either inhibition or excitation of these basket cells can then lead to reduced synchronized activity in the gamma band. Interestingly, this anomaly can also indicate neurological disorders such as autism and schizophrenia. These circuit anomalies may also be responsible for the thought disorders that often accompany schizophrenia.

We also learn (ibid.):

"When it comes to laying down memories, the relative timing of spikes seems to be as important as the rate of firing. In particular, the synchronized firing of spikes in the cortex is important for increasing the strengths of synapses- an important process in forming long term memories."

A synapse is "strengthened" whenever the firing of a neuron on one side of a synapse incites the neuron on the other side to register a stronger response. See e.g. the diagram below:

















How critical is this timing aspect? In 1997, researchers at the Max Planck Institute for Medical Research in Heidelberg, Germany,  found that a 20 milliseconds variance is all that's needed to throw a memory off. Thus, assuming a frequency in the gamma range, if an input at a synapse is consistently followed - within 10 milliseconds- by a spike from the neuron on the other side, then the memory is likely sealed. However, if the converse occurs, i.e. the neuron on the other side fires 10 milliseconds before the first one  all bets are off. The strength of the synapse between the cells decreases and the memory is then either fuzzy or lost.

The article ends by noting: that some of the strongest evidence that synchronized spikes may be important for memory comes from research by Gyorgy Buzsacki of New York University on the hippocampus. He found that the spiking of neurons in the hippocampus and other cortical regions it interacts with is strongly influenced by synchronous oscillations of brain waves in a range of frequencies from 4 to 8 hertz (the theta band). It seems that these theta band oscillations can coordinate the timing of spikes and have a "more permanent effect on the synapses."

This means the memory produced will be more long term, and better, more reliable.

In the end, memory is seen to be very dependent on synapse strengths and synchronization of specific types of waves (gamma and theta bands). If any one element is missing or off, then the memory simply can't be depended upon to yield accurate information - or maybe any information.

The moral of the story is that if we intend to trust our memories we better have those which resemble  the "memory masters" who possess the ability to recall what events happened on every day of their lives, e.g.
http://www.dailymail.co.uk/health/article-1340162/Memory-masters-The-people-rememberl-exactly-happened-day-lives.html

Failing that, we better learn to keep meticulous journals or take photographs of every major event we attend!

As for the key question: Why can't I remember that? The fault may not lie in one's 'stars' but in his synchronous spikes in the gamma band!

Is the Psycho Gaming the System? Could be....

J                
James Egan Holmes: The 'Butcher' of Aurora. Is he gaming the system?

The blogosphere buzz now is that the Aurora Mass Murderer (let's cut the crap here, and leave out all the "alleged killer" BS - he surrendered to the police decked out in his bloody kevlar and other gear) is gaming the justice system. This meme has arisen in the wake of the discovery that he sent a notebook bearing all his massacre plans to a therp that was treating him at the University of Colorado-Anshutz. Evidently, this therapist - Lynne Fenton- had been treating the guy for schizophrenia .

Left unresolved, especially after a judge has sealed further records disclosure from the university, is whether Holmes knew in advance how this would unfold. It is possible that he deliberately decided to seek therapy services from this senior person in the hope that it might later be exploited to make the basis for an "insanity" plea.  Leaving out all the other distractions, I simply believe Holmes - if this was indeed his plan - made the wrong choice of illness. He is definitely (ok, let's say instead with 90% probability) not schizophrenic - since his behaviors don't fit that cluster of traits as defined and explicated in the DSM-III and IV.  To recall for readers, The DSM-III, IV (Diagnostic and Statistic Manual of Mental Disorders) provides a classification of personality disorders and identifies 'clusters' within which specific disorders can occur. These include:

(A) Schizotypal, paranoid and schizoid personality disorders ('odd, eccentric' cluster)

(B) Borderline, narcissistic, histrionic and anti-social personality disorders ('dramatic, emotional, erratic')

(C) Submerged: Avoidant, dependent, obsessive-compulsive, passive aggressive personality disorders('anxious, fearful')

Each Cluster has discrete tendencies within itself:

(A) -> withdraw (no wants from others)

(B) -> exploit (want from others without seeing or responding to what others want from them)

(C) -> comply (want from others, but yields only to others' wants to avoid conflict)

As I showed in my several prior blogs, beginning with Deconstruction of a Psycho Holmes' profile and attributes (as we have assimilated them from sundry reports) fit in with the tendencies in the last (C) ensemble and hence fit the profile of a submerged personality, not a schizophrenic. Also, I have had the experience of observing paranoid schizophrenics at the Black Rock (Barbados) Mental Health Sanatorium in the 70s, and NONE of them demonstrated any capacity for mega-violence of the form James Eagan Holmes manifested via his aggressive pseudo-ego,  the Joker.

Now, let us bear in mind another critical aspect as this case slowly wends its way to trial (which I am now informed  may not be for two years):  A person cannot be tried for a crime unless he is competent to stand trial. To be competent, he must be oriented as to time and place, comprehend the charges against him, appreciate his legal peril, recall the events that caused him to be charged, and be able to communicate with and assist their attorneys to defend him.

It is not, at this time, evident that Holmes meets any of these criteria.  Indeed, according to the (UK) Telegraph, Holmes claims that he does not recall the incident. If that is true, he is incompetent to stand trial.

Why should he not recall it? As I explained in my 'Parsing of the Submergent Psycho- Part II  his incarceration "has torpedoed the 'Joker' (the aggressive pseudo-ago) who is thereby rendered impotent and inactive. What we are seeing is the first emergence of Holmes' authentic self and the expected SHOCK because frankly, HE doesn't know what the hell happened! After all, it was the pseudo ego 'Joker' that did the deed, then vacated or was vacated. Now, the authentic or previously submerged ego is left to wonder what the hell is going on."

So no wonder he has that vacant, million light years distant stare on his face. I also added (in the same blog):

"His self has been dissociated, and the guilty perp -ego is now gone, fled the coop as it were, to leave the authentic 'James Holmes' ego and self to bear the cost"

In other words, to spell it out, Holmes as his authentic (earlier submerged) self, truly can't recall the incident or what he did. He can't because a distinct, different ego (self) perpetrated it. This aggressive pseudo ego masterminded all the planning, as well as execution, while Holmes' submerged self was unavailable and 'out for the count'. His contact with therapist Lynne Fenton may actually have been a last ditch desperate effort to contact the mother-pseudo ego for some kind of relief. (With Fenton embodying the mother ego). We may never know.

The other real horror (apart from the lives shattered and lost at the theater) may be that the authentic self - who had no clue what was transpiring - will be executed for what his alter ego ("Joker")  did to those 70 people at an Aurora movie theater.