When infants pay attention to their caregivers, the caregivers attempt to stimulate them. When infants withdraw attention, caregivers reduce their efforts at stimulation. This illustrates the concept of

What is the procedure known as flash suppression?

a. An observer is not conscious of a stimulus that flashes onto a screen too briefly. b. Activity in the cones of the retina inhibits activity in the rods. c. Dots flashing on and off block conscious perception of a stationary object. d. A conscious observer may have brief periods of momentary unconsciousness.

Which part of a normal human neuron gets twisted together to form a neurofibrillary tangle?

a. neurotransmitters b. somas c. dendrites d. axons