The Brain From Inside Out

Question 1

Explain how the good enough and precision brain work

Answer 1

Good enough- networks of neurons with stronger operating characteristics, that allow any situation to be deemed known

Precision- majority of plastic neurons that help redefine events (learning)

Question 2

In the preconfigured brain, learning is a…?

Answer 2

Matching process, in which preexisting neuronal patterns acquire meaning with experience, which requires grounding in action

Question 3

Explain: brains do not process information: they create it

Answer 3

The brain interacts with the outside world through actions, and through those interactions derives meaning/information

Question 4

Why is causation difficult to comprehend in the brain?

Answer 4

The brain is a self-organized, complex system where events “emerge” from the interaction of elements, not linear causation

Question 5

The process of updating predictions of the world is…?

Answer 5

Perception

Question 6

How do growing axons know which to innervate? Explain via spindle-shaped oscillatory patterns

Answer 6

During infancy, the spindle oscillation binds together neuronal groups that are coactivated in sensory cortical areas as a result of simultaneous muscular movement

Question 7

What is a neuronal cell assembly?

Answer 7

A population of neurons upstream, whether directly synapsed together or not, that lead to a discharge of their target neuron within 10-30ms of each other. This window is needed for the downstream reader to integrate the incoming signals

Question 8

Explain, cognition depends on prior action-based experiences of the world

Answer 8

Action based experiences lead to internally generated sequences being able to test “what if” scenarios and anticipate consequences

Question 9

How does the hippocampus interact with thalamocortical loops?

Answer 9

The hippocampus generates sequential neuronal activity to organize thalamocortical activity into orderly trajectories (allowing memory and planning)

Question 10

How is dead-reckoning navigation and episodic memory related?

Answer 10

They require self-referencing and travel through time and space

Question 11

how are allocentric/map based navigation and semantic memories similar?

Answer 11

Both require exploration and lead to explicit knowledge, not tied to a self-referencing

Question 12

Describe the role of interneurons

Answer 12

Route excitatory information at correct time and target direction

Question 13

Neural networks fall within certain frequency bands of oscillation, how do those lead to brain states?

Answer 13

Neighboring frequency bands within the same neuronal network are typically associated with different brain states and com- pete with each other

Question 14

How do slow oscillations effect fast?

Answer 14

widespread slow oscil- lations modulate faster local events

Question 15

What is the relationship between neural network size and frequency of oscillation

Answer 15

Higher frequen- cy oscillations are confined to a small neuro- nal space, whereas very large networks are recruited during slow oscillations

Question 16

What is the relationship between synchrony and integration of neural inputs?

Answer 16

Integration of information requires “synchrony” of the convergent inputs. Synchrony is defined by the temporal window within which some trace of an earlier event is retained, which then alters the response to a subsequent event.

Question 17

How do oscillation effect perception?

Answer 17

The systems level implica- tion of these oscillation-gating functions is
that perception is not a continuous event but is subject to the cyclic changes of the net- works processing the input

Question 18

What are the two ways to create neuronal sequences?

Answer 18

Changing environmental or proprioceptive stimuli

Internally driven self-organized patterning

Question 19

How do oscillations coordinate sender and receiver neuron activity?

Answer 19

They temporally coordinate the activity of sender and receiver populations to ensure proper timing

Question 20

What does active sensing mean?

Answer 20

A motor command informs the sensory system via a corollary charge adjusting the sensor

Question 21

Describe the reader sender relationship between the hippocampus and neocortex

Answer 21

The hippocampus (reader) initiates transfer of neuronal messages via theta phase control of neocortical networks. Hippocampal theta oscillations can bias gamma oscillations at neocortical locations, leading to neocortical messages contained in gamma waves arriving at the hippocampus in the best phase of theta cycle to absorb the info. During sleep this happens in reverse

Question 22

What is the call up hypothesis of information exchange?

Answer 22

Information transfer in the brain is initiated by slow oscillations produced by the receiver. The sender thus delivers info during sensitive phases

Question 23

Describe the interaction between internal and external mechanisms in neural trajectories

Answer 23

Internal self-organized networks are periodically disrupted or influenced by external stimuli

Question 24

What is the difference in information flow direction between encoding and recall?

Answer 24

During encoding- outside in to neocortex to hippocampus

Recall- hippocampus to neocortex

Question 25

How does learning occur from preexisting neural trajectories?

Answer 25

When a spontaneous neural trajectory coincides with a useful action, meaning of the trajectory is obtained.

Question 26

Why the size of the mammalian neocortex so key in learning?

Answer 26

The neocortex acts as the “reader” to hippocampal generated neural trajectories. Through experience dependent events, the neocortex can link the trajectories to meaningful action

Question 27

What is the role of sharp wave ripples in the hippocampus?

Answer 27

Compresses the discrete concepts of past and future into a continuous stream.
Acts to predict upcoming behavior and assess previous behavior outcomes

Question 28

Explain the consolidation model of memory formation?

Answer 28

During learning, afferent activity from neocortex-entorhinal pathway brings about a change of synaptic strengths in hippocampus. The learned info is temporarily held here. A period follows where the neurons and synapses that were used during learning process are reactivated via sharp wave ripples. During non-REM sleep, this activity repeats over and over again

Question 29

How does the prefrontal cortex act as an action simulator?

Answer 29

The PFC connects to autonomic and limbic sites, where it sends corollary discharges to inform motivation/action preparing structures about pending action plans.