One of the feature of 'intense' memories is an apparent slowing of subjective time; time 'stops'.

Elsewhere I have emphasized the empirically discovered effects of fluctuations of metabolic rate on subjective time assessment.

What is common here is the increase of heart rate, and therefore metabolic processing, and the apparent slowing of time, together with the slowing of heart rate and the apparent increase in time. These rates are analogous to relativistic effects on time and matter as a result of acceleration and deceleration. Irrespective of size, we are all energy systems. (Metabolic rate is the rate at which we convert, or oxidize, mass into energy).

"Researcher John Cacioppo artificially accelerated the hearts of 14 people by adjusting their cardiac pacemakers. When he accelerated their heart rates to 88 beats per minute - 16 beats faster than the normal - their reading comprehension, ability to write complicated sentances, and capacity to develop a line of argument all showed improvement."(Omega - May/June 1981 p106)

There are "well-established effects of temperature on cell physiology: high temperatures facilitate transmitter release and hyperpolarize cell menbranes, respectively increasing synaptic potentials and decreasing the population spike." p163 (Eichenbaum & Otto 1993)

In the brain of rats, the hippocampus, an area of the brain strongly linked with memory, registers "2-3°C increases in.. temperature..during exploration" p163 (Eichenbaum & Otto 1993)

An increase in metabolic rate would slow down subjective time. If information is associated with assimilation and organization than here we have more time to gather one's thoughts.

There is a limit to this at both ends of the information processing continuum as demonstrated by hypothyroidism and hyperthyroidism. The former is a condition resulting from a slowing down of metabolic rate. With this condition, information assimilation is impossible with subjects being classified as 'cretans'. Hyperthyroidism results from an excessive metabolic rate. The condition leads to extreme agitation and hyperactivity often followed by psychosis.

Both these conditions are diseases of the thyroid gland which is controlled by hormonal signals received from the pituitary/hypothalamus system of the limbic brain. The thyroid gland produces thyroxine which affects metabolism.

It is suggested that the process of learning, the period of time in which information can be assimilated, is controlled by the metabolic rate of the person doing the learning.

This rate would be strongly correlated with rCBF and the attention system.

"The length of the period of a biological rhythm - the time [earthtime] between one peak of activity and the next - may be independant of temperature but the amplitude - the maximum peak-to-trough range of the rhythm - tends to vary with temperature"(Insight No30 p820)

Amplitude is a function of energy. A simple geometric exercise shows the point. Consider the following diagram:

                    A .....................
                     /          Z          \
                    |-----------------------|
                    x                       y

The strait line joining x and y symbolizes the passing of one second of earthtime (fixed). The line xy can be considered as a wave with amplitude of zero. Let the line A have an amplitude of Z. The distance along A is now longer than that of line xy. If we define xy as equal to one second of time, then by increasing temperature the amplitude approaches Z (line A). If we measure time using line A, although xy is unchanged in that it equals one second of 'real' time, line A is such that time is experienced as greater than one second (say 2 seconds). Of interest is the possibility that information assimilation is controlled by internal clocks. If I can assimilate x bits of information in one earth-second, than the above case shows that, with an increase in metabolism, I can assimilate 2x bits of information in one earth-second.

A good example of this distortion is found in children. The younger they are the higher their metabolic rates in proportion to their size. The time distortions can be huge, where one hour for an adult could be three hours for them. This is a possible reason for the loss of early childhood memories as we get older. Using the 'state-specific memory' model, an adult would need to raise metabolic rate to that equivalent of childhood to possibly recall memories. This may explain the tendancy for high temperatures during illness to lead to patient showing behavioural 'age' regression.

Although speeding oneself up may be advantageous, there are prices to pay:

(1) The state specific memory concept implies that to recall accellerated learning information I would have to be in the same state as when I learnt the information. (Very early childhood memories are often hard to recall even though the brain is well developed at an early age).

(2) Energy is not free. The average human breaths once for every four heartbeats, about 600,000,000 times in a lifetime. The average human burns as bright as a 60-75W lightbulb with the brain utilizing 4-10W. By speeding up metabolism without a recovery period (slowing down to compensate for the speedup) one's alloted time diminishes. This compensation is demonstrated in the fact that going to sleep with a high metabolic rate doubles the period of time one would sleep with a normal metabolic rate. In other words, the sleep period is extended. Interrupting this natural process with alarm clocks increases overall stress on the body and heightens the possibility of organ breakdowns as they near their 'best-before' dates! If we abide by the internal clock then the time we are asleep is being utilized by the 'slow' learner and the total information gain may only be the same.

(3) The thyroid diseases show that there are limits.

There seems to be a set rate for successful, longstanding, information assimilation. Within this window there seems to be a rate-bias by PROCESS or FORM dominant thinking, where the PROCESS bias is faster (relational bias) but context poor (hierarchy bias) whereas the FORM bias is slower but more detailed. These are, again, extremes. The average allows for a paced development but it is the non-average that enables us to understand the middle. My own theoretical research suggests that minimal changes in temperature (100ths of a degree) can cause significant time distortions (5 secs per minute).

Is the ability to activate, what Antonio Damasio calls, 'somatic markers' dependent on the flow of time? A high-speed individual my only be able to connect with gross markers (Schizophrenia) whereas as slow-speed individual may only be able to connect with many fine markers (Depression). Both these extremes will generate abnormal social behaviour. Both problems are tied to one event - metabolic rate and the resulting time distortion.