BiologicalHierarchyReduced

Biological Hierarchy Reduced

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This page is reduction of Full Biological Hierarchy for the purpose of modeling in aHuman.

Biological Reduction Rationale

• reduction hierarchy contains only functions copied to aHuman
• visual brain functions are regarded as generic sensory approach
• motor is replaced by effector, movement is action
• body remained as term, but its nature is completely different for aHuman

* task performed for the mind is the same - default reward system and mandatory part for any action
* hence somatosensory brain elements remained predefined mandatory sensor, body feeling.

• single hemisphere is assumed to be enough
• blood and heart are regarded as regulatory functions, controlling resources spent by brain
• thalamic area is primarily considered as relay, and to simplify picture, some direct ways, e.g. ACA to HCA are treated as passing via THA
• limbic lobe was split into parts allocated to other modules, because parts of limbic system seem to me quite different while having strong connections to specific parts

* anterior cingulate cortex has strong bidirectional connections with anterior cortex and allocated to ACA, posterior cingulate - to PCA as well
* secondary role of thalamic area is spreading of modulatory activity (sleep-awake cycle, hormones, neurotransmitters and others), and because of that septal nuclei allocated to THA 
* hippocampus is strong aligned with memory formation functions of temporal lobe - enthorinal and perirhinal cortices and eventually allocated to HCA
* fornix is hippocampus communication facility and that's why allocated also to HCA
* basal ganglia is rational primitive motor system and needs to be separate module because it is one of major non-cortical functions
* amygdala is allocated to BGA because generating movements by emotional, but not rational signals

Biological Brain Hierarchy Reduction

• neocortex

* frontal lobe
 * *prefrontal cortex* (personality, judgement, complex planning, inhibition, morality)
  * *orbitofrontal cortex* (involved in sensory integration, in representing the affective value of reinforcers, and in decision-making and expectation)
 * *premotor cortex* (patterned effector actions and planning)
 * *primary motor cortex* (individual actions)
  * *frontal eye fields* (control specific sensor)
* parietal lobe
 * *primary somatosensory cortex* (anterior, basic sensations of the body)
 * *superior parietal lobule* (posterior, body sensations relationships, locating objects in space)
 * *inferior parietal lobule* (posterior, semantics, involved in reading both in regards to meaning and phonology)
 * *intraparietal sulcus* (posterior, essential in guidance of limb and eye movement)
 * *general interpretation area* (opinions)
* occipital lobe
 * *primary visual cortex* (simple specific sensor spatial primitives)
 * *visual associations* (intermediate specific sensor spatial and temporal patterns)
 * *fusiform gyris* (object representation from specific sensor)
* temporal lobe
 * *insula* (habits, visceral sensations)
 * *parahippocampal gyrus* (formation of spatial memory, encoding and recognition of scenes)
  * anterior parahippocampal gyrus
   * *perirhinal cortex* (specific sensor perception and memory, facilitates recognition and identification of environmental stimuli)
   * *entorhinal cortex* (hub in a widespread network for memory and navigation, autobiographical/declarative/episodic memories, memory formation, memory consolidation, and memory optimization in sleep)
  * *posterior parahippocampal gyrus* (spatial declarative memory)

• limbic system

* *cingulate cortex* (life resources consumption control, cognitive and attentional processing)
 * *anterior cingulate cortex* (error and conflict detection processes)
 * *posterior cingulate cortex* (episodic memory, emotion, navigation, resting)
* amygdala (signalling cortex of motivationally significant stimuli)
* *septal nuclei* (controller of theta rhythm, major source of projections to hippocampus)
* *hippocampus* (detection of novel events, places and stimuli, spatial coding)
 * *dentate gyrus* (formation of memories, distinguishing multiple instances of similar events or multiple visits to the same location, stress and depression)
 * *subiculum* (spatial relations, working memory)
 * *fornix* (carries signals from the hippocampus)
* basal ganglia (primitive effectors system)
 * *striatum* (planning and modulation of actions)
  * *caudate nucleus* (part of the learning and memory system)
  * *putamen* (regulate actions and influence various types of learning)
  * *nucleus accumbens* (reward, pleasure, addiction, fear)
   * *nucleus accumbens core* (acquisition and maintenance of a new strategy)
   * *nucleus accumbens shell* (mediate learning about irrelevant stimuli)
 * *pallidum* (reward and incentive motivation)
  * *globus pallidus externa* (main regulator of the basal ganglia system)
  * *substantia nigra* (reward, addiction, and actions)
 * *subthalamic nucleus* (action selection)

• diencephalon (relay system between sensory input neurons and other parts of the brain)

* thalamus (relaying sensation, spatial sense and motor signals to the cerebral cortex, regulation of consciousness, sleep and alertness)
 * *specific relay nuclei* (project to/from specific functional area of neocortex)
  * *lateral geniculate body* (specific sensor -> specific sensor cortex area)
  * ventral posterior nucleus
   * *ventral posterior lateral nucleus* (body sensations -> primary somesthetic area)
  * *ventral lateral/anterior nucleus* (effector control feedback from cerebellum and striatum -> primary effector cortex)
 * *association nuclei* (project to association areas)
  * *anterior nucleus* (mammillary bodies, hypothalamus, cingulate gyrus -> cingulate gyrus, hypothalamus, and hippocampus)
  * *medial nucleus* (somatic sensory input from hypothalamus, amygdala -> prefrontal cortex, hypothalamus, hippocampus, striatum)
  * *lateral nucleus* (hypothalamus, cingulate gyrus -> cingulate gyrus)
  * *posterior group nuclei* (pain from spinothalamic tract and 5th cranial nerve -> insula)
  * *pulvinar nuclei* (reciprocal connections with association areas)
 * non-specific nuclei
  * *intralaminar nuclei* (basal ganglia, reticular formation -> all parts of neocortex, effector control system, perceptions of various modalities)
  * *reticular nuclei* (from all fibers leaving and entering the thalamus -> all thalamic nuclei, cortical regulation of the thalamic activity)
* *hypothalamus* (modulatory, life support and the sleep/wake cycle)
 * *mammillary body* (relay from the amygdala and hippocampus to thalamus)
 * *median eminence* (stimulate or inhibit the release of hormones from the anterior pituitary)

• *brain stem* (main sensory innervation)

* *medulla oblongata* (autonomic, involuntary functions, relays nerve signals between the brain and spinal cord)
* midbrain
 * tectum
  * *superior colliculus* (preliminary specific sensor processing and control of specific sensor)
 * cerebral peduncle
  * *midbrain tegmentum* (involved in many unconscious homeostatic and reflexive pathways)
  * *crus cerebri* (contains effector tracts)
  * *substantia nigra* (sensor control, effector planning, reward seeking, learning, and addiction)
* *pons* (relay signals from the forebrain to the cerebellum, along with nuclei that deal primarily with sleep, equilibrium, sensor control, expressing emotions)
 * cranial nerves
  * 2 - *optic nerve* (transmits specific sensor information to the brain)
  * 3 - *oculomotor nerve* (perform most sensor control)
  * 4 - *trochlear nerve* (perform certain sensor control)
  * 6 - *abducens nerve* (perform certain sensor control)

• *cerebellum* (complex actions, sequential thinking, attention, coordination, precision, and accurate timing)

* peduncles
 * *inferior cerebellar peduncle* (to/from medulla/spinal cord)
 * *middle cerebellar peduncle* (from pons)
 * *superior cerebellar peduncle* (to midbrain)
 * *arbor vitae* (brings sensory/motor information to/from cerebellum)
* *spinocerebellum* (control actions power and coordination of multiple actions, cerebellum/basal ganglia/neocortex effector actions)
* *cerebrocerebellum* (participates in planning actions, sensory/prefrontal -> cerebellum -> thalamus -> motor cortex -> effectors
* *choroid plexus* (inhibits neuronal maturation)

• spinal cord

* *anterolateral system* (body feeling pathway)
* *corticospinal tract* (effector pathway for upper effector neuronal signals coming from the cerebral cortex/basal ganglia)
 * *lateral corticospinal tract* (distal effector actions)
 * *anterior cortical spinal tract* (affect general body state)
* *ventral spinocerebellar tract* (proprioceptive information travels up the spinal cord)
* *dorsal spinocerebellar tract* (conveys inconscient proprioceptive information)