Brain Models Built From Timing Devices:
Eyes That Look at Objects

Viewed from an alternative approach, an Eye for Sharp Contrast offers numerous opportunities for improvement and development. This page proposes some improvements and possible developments.

As a place for ongoing development, this page is subject to supersession. The present first publication identifies matters for further detailed development.

Proposed Improvements

 

1. Frequency multiplication of the edge signal.

Reduces waiting time, W, by as much as 2/3.

2. Bursting timing devices.

Four pulses per δ for as many as 4 δ, balanced by a long recovery period between bursts.

3. Echelon design for the Bundle Cycler.

Reduces cycle time from 20 δ₀ to about 7 or 8 δ₀.

4. Development of the Edge Detector.

A single Edge Detector becomes the point of origin of a kit of parts of various Edge Detectors and sub-parts of Edge Detectors. Edge signals from multiple Edge Detectors function like Intermediate Outputs and can be assembled into hierarchical structures with many variations. A retina-like area can be mapped into a checkerboard pattern of Edge Detectors with alternating horizontal and vertical sensitivities.

5. Hierarchical vs. Quad Net sensory systems.

Hierarchical methods that combine and extract useful signals from area arrangements of Edge Detectors require long processing times. Quad Nets appear to offer possibilities for faster processing with more capacities. For purposes of comparing timing device processes and Quad Net processes, it is useful to recall the Carnot cycle from thermodynamics. The Carnot cycle has two kinds of processes: isothermal processes and adiabatic processes. In timing device processes, timing intervals such as β's and δ's remain constant while input pulse patterns change; these are like isothermal processes. Quad Net processes are more general. Some Quad Net processes are like adiabatic processes: pulse patterns within device parts are subjected to changing β's and δ's and changes occur without external inputs. Shimmering Sensitivity can be generated in a Quad Net device part during such an "adiabatic process" as δ > β changes to δ < β and a phase change occurs. When such a Quad Net device part is hooked up to a source of sensation, processing can be carried out in a single cycle of the Quad Net device part. [In the theory of simple engines, any process can be approximated by a sequence of alternating isothermal and adiabatic processes, like approximating a smooth curve by a sequence of flats and jumps.]

6. Saccadic (jumping) activity of the Level Shifter.

Additional inputs to the Level Shifter can allow for random access to particular levels, in addition to the linked action of the present design. To the extent the material properties of the Lens allow, an improved Eye should be able to jump from one focal point to another focal point, where now it is necessary to crawl between them.

7. Detection and following of transverse motion and perhaps color.

The path of construction leads to combination of previous proposed improvements, which are adapted to drive the more complex muscular system that moves the Eye in its orbit so that it can look in variable directions. Eyes that Look at Objects are designed to detect and follow objects that are moving across the field of vision. The four-fold (plus two) musculature of the human eye that controls such capacities appears to be congruent with Quad Net capacities. In addition, aspects of color vision (involving red-green and blue-yellow balances between color-specific sensors) suggests that color patches may also be amenable to Quad Net detection in a similar fashion.

8. Simultaneous operations using multiple capacities.

We use our eyes as an instrument of our wills, looking where we please and taking advantage of multiple visual capacities, including those that operate reflexively such as looking toward a source of sound or the Vestibular-Optical Reflex discussed in the technical paper, ( ... ) "An Ear for Pythagorean Harmonics." A chief goal of development is a visual system that performs multiple tasks with respect to edges and patches and that coordinates simultaneous operations, including happenstance interruptions and seizures of control by an external volition.

( ... ) Link List

( ... ) top of page

Frequency multiplication of the edge signal.

In present designs of the Eye for Sharp Contrast, a large amount of time is spent "waiting" for a possible output signal from the comparison unit. The wait is needed to detect a low frequency signal. To detect a signal with 2 to 3 pulses per second requires .33. sec to .5 sec. for assured detection.

It is possible to insert a frequency multiplication device in the line carrying the edge signal to the comparison unit, as shown in the adjacent Figure. A 3-to-1 multiplication is proposed. Suppose that during operations the edge signal goes down from 19 pulses per second in one cycle to 17 pulses per second in the next cycle, a difference of 2 pulses per second that should be detected for successful performance, requiring 0.5 sec. to detect with assurance. When the edge signal is multiplied by 3, the resulting frequencies are 57 pulses per second and 51 pulses per second, with a difference of 6. Only .17 sec. is required to detect this signal with assurance, a third of the value without the frequency multiplication device.

An appropriate frequency multiplication device is a ( ... ) streaming device from the Kit of Parts. The desired streaming device has a specification of 1/3. This means that the input signal is treated as a succession of periods between pulses. The most recent input period is the time interval between the most recent input pulse and its predecessor. When a new input pulse arrives, a new most recent input period is determined. The output period is based on the most recent input period. When an output pulse is discharged, the device sets the period to the next output pulse discharge and that period is 1/3 of the most recent input period.

The effect of the 1/3 streaming device is to produce an output signal with a pulse frequency that is three times that of the input signal.

Use of the 1/3 streaming device requires adjusting the system to meet increased demands. The maximum edge signal is 33 pulses per second, based on a juxtaposition of the two end-of-range limit points of sensorial response, dark and bright extremes. That is, the maximum edge signal, 33 pulses per second, is a difference signal produced from two sensory-modulated signal generators generating 17 and 50 pulses per second respectively. Multiplying that maximum edge signal by 3 produces 99 pulses per second.

The maximum carrying capacity of a timing device where δ = δ₀ and β = 0.1 δ₀ is 1/(1.1 δ₀); in the case where δ₀ = 0.01 sec., the maximum carrying capacity is about 90 pulses per second. However, another standard timing device specification used in the Eye for Sharp Contrast is δ' = 0.8 δ₀ and, for such a specification and the same β, the carrying capacity is 111 pulses per second, sufficient for operations using 3-to-1 frequency multiplier.

The improvement requires additional modifications in other parts of the system, e.g., to the Ξ bundle storage device.

( ... ) top of page

Bursting timing devices.

The bursting timing device generates a number of pulses with a very short period between pulses. In a specific proposed design, pulses are produced at a rate of 4 per δ in a burst of up to 16 pulses. Bursting timing devices use a different way of organizing response periods and refractory periods. In the bursting timing device, there still a response period between the arrival of a trigger pulse and the first pulse of a burst; but there is neither response period nor refractory period for later pulses in the burst. A single long recovery period occurs after all the pulses in the burst. The single long recovery period plus one responding period is equal to the sum of the response periods and refractory periods for all the separate pulses.

The principles that govern the bursting timing device are those discussed in the Quad Net Model. The principles involve "virtual energy." A steady stream of virtual energy fuels the operations of each timing device. If a timing device operates with δ = 0.008 sec. and β = 0.001 sec., as in the original Bundle Cycler, enough virtual energy flows into a device in 0.009 sec. to generate a pulse. In the primal timing device, there is only enough storage for one pulse; energy arriving after the first 0.009 sec. is dissipated. For 16 pulses, .144 sec. is required. The bursting timing device has enough storage for 16 pulses and 0.144 sec. are required between bursts so that this storage can be filled if necessary. Because one response period is still required to generate the first pulse after the arrival of the trigger pulse and because the signal bloc of 4 δ is separate, the recovery period for the bursting timing device is 0.144 sec. and the minimum cycle period is 0.184 sec. If the period between bursts is more than 0.184 sec., the excess time is spent in the "readiness" condition.

The bursting timing device suggested here has a counter that enables it to discharge the same number of pulses as it receives. A more complex bursting device generates a variable number of pulses that is controlled through an additional input.

The chief advantage of the bursting timing device is finer control over activity of muscle fibers. Multiple bursting devices can stimulate a single muscle fiber, which can be re-configured for faster response and smaller twitches. A second finer system can be interwoven with the first coarser system. Having two systems provides possibilities for enhanced control and for combinations.

( ... ) top of page

Echelon design for the Bundle Cycler.

The Figure below shows a revised design for the Bundle Cycler. The purpose of the revision is to enable faster muscular response; new motor signals can be introduced more quickly, almost four times as fast. The design employs bursting timing devices.

The proposed system uses four of the revised bundle cyclers. The four cyclers are themselves connected in a cycling way through links involving "unattached" projections from timing devices 13 and onto linking timing devices 17, which serve as circulation connectors. Alternative operations allow for slow changes with a single motor signal input and sequential transmission through 4 bundle cyclers or for fast changes with a fresh motor signal seizing control of all bundle cyclers in one swoop. Using figures from the discussion on bursting timing devices, fast changes can occur four times in 0.184 sec. or about every 0.046 sec., equal to about 6 δ..

( ... ) top of page

Development of the Edge Detector.

The Edge Detector has potential for development in several directions.

As shown in the adjacent Figure, Intermediate Outputs can be generated that are additional to those in the original Edge Detector. Classes of Intermediate Outputs are generated simultaneously and may be useful in controlling operations.

As shown in the adjacent Figure, an Edge Detector can be symbolized and viewed as two "sub-parts" connected through Intermediate Outputs. The "primary sub-part" contains the light-sensing devices and generates Intermediate Outputs. The "secondary sub-part" receives Intermediate Outputs and generates the edge signal. Edge Detectors and sub-parts become units in various possible constructions.

In the assembly shown in the adjacent Figure, Edge Detectors generate edge signals and the edge signals function like Intermediate Outputs that are received by the secondary sub-part. The result is a hierarchical structure that can be extended for an indefinite number of layers with controllable interfaces between levels.

The adjacent Figure shows development of the Edge Detector into a two-dimensional area. Edge Detectors and/or sub-parts are alternatively oriented in horizontal and vertical directions. Construction methods can potentially combine classes of Intermediate Outputs, hierarchical processing and two-dimensional configurations.

( ... ) top of page

Hierarchical vs. Quad Net sensory systems.

No content at this time.

( ... ) top of page

Saccadic (jumping) activity of the Level Shifter.

No content at this time.

( ... ) top of page

Detection and following of transverse motion and perhaps color.

No content at this time.

( ... ) top of page

Simultaneous operations using multiple capacities.

No content at this time.

( ... ) top of page

Link List

"Brain Models Built From Timing Devices"

( ... ) top of page

Related Materials

Your comments and suggestions are welcome. Please write to the adjacent email address (shown in an image to minimize spam).

2/5/11

Copyright © 2011 Robert Kovsky