Circuit Elements Required for Neural Systems - Brain Theory from a Circuits and Systems Perspective - page 56

Enabled Logic

13. Explain how enabled neural logic works as in this chapter?

(a) Explain the two-input enabled OR gate (HINT: 50 mV is provided for
enabling, and 50 mV or more from any input will trigger the subject soma,
assumed to trigger at 70 mV)
(b) Explain the two-input enabled AND gate (HINT: 50 mV is provided for
enabling, and 25 mV from each input will trigger the subject soma,
assumed to trigger at 70 mV)

14. Provide a table that list all:

(a) Dendritic logic elements
(b) Enabled logic elements
(c) Other types of circuit elements (HINT: Refer to symbols mentioned in this
chapter)

15. Write out a truth table for:

(a) The AND function, that is, AND(a, b)
(b) The OR function, that is, OR(a, b)
(c) An exclusive OR, that is, XOR(a, b)
(d) An exclusive NOR, that is, XNOR(a, b)
ANS.

a b AND(a, b) OR(a, b) XOR(a, b) XNOR(a, b)

0 0 0 0 0 1

0 1 0 1 1 0

1 0 0 1 1 0

1 1 1 1 0 1

(e) Locate a NOT function in the table (ANS. Let a ¼ 1 and mark the XOR

versus b)

16. Provide a diagram of the simplest possible NOT gate using a neuron and
neurotransmitters, using the symbols of this chapter. (HINT: Refer to

Fig. 3.18 .)
17. What extra requirements are there for the neural NOT gate?

(a) Using dendritic XOR gate (ANS. an auxiliary burst of synchronized pulses
is necessary during operation)
(b) Using enabled gate (ANS. inhibitory neurotransmitters and an auxiliary
burst of pulses is necessary during operation)