8. Role of the hypothalamus, reticular formation, cerebellum, basal ganglia and cerebral cortex in the control ofautonomic functions. Integration of the central nervous system in the adaptation processes of the body - "alarm" or "stress" response of the sympathetic branch ofthe ANS.

8. Role of the hypothalamus, reticular formation, cerebellum, basal ganglia and cerebral cortex in the control ofautonomic functions. Integration of the central nervous system in the adaptation processes of the body - "alarm" or "stress" response of the sympathetic branch ofthe ANS.

in this title, what do you include for this whole part:

Integration of the central nervous system in the adaptation processes of the body - "alarm" or "stress" response of the sympathetic branch ofthe ANS.

the neural/hormonal pathways

role of hypothalamus

• Maintains homeostasis by regulating:

  • Sympathetic and parasympathetic balance

  • Endocrine functions

  • Emotional and behavioral responses

• Autonomic control:

  • Anterior hypothalamic nucleus:

    • Activates parasympathetic nervous system

    • ↓ Body temperature (via vasodilation, sweating)

  • Posterior hypothalamic nucleus:

    • Activates sympathetic nervous system

    • ↑ Body temperature (via vasoconstriction, shivering)

• Limbic functions:

  • Involved in emotion, memory, feeding behavior, learning

• Endocrine control:

  • CRH → ACTH → adrenal cortex → cortisol

  • TRH → TSH → thyroid gland → T₃/T₄

  • GnRH → LH & FSH → gonads → sex hormones/gametes

  • GHRH → GH → liver/tissues → IGF-1

  • Somatostatin → inhibits GH and TSH

  • PRH → Prolactin → milk production

  • ADH (from supraoptic nuclei) → acts via posterior pituitary

  • Oxytocin (from paraventricular nuclei) → acts via posterior pituitary

(this is just clarifying what they stand for:

Abbreviation	Full Form	Function

CRH

Corticotropin-Releasing Hormone

Stimulates ACTH release

GnRH

Gonadotropin-Releasing Hormone

Stimulates LH & FSH release

GHRH

Growth Hormone-Releasing Hormone

Stimulates GH release

TRH

Thyrotropin-Releasing Hormone

Stimulates TSH (and prolactin) release

ACTH

Adrenocorticotropic Hormone

Stimulates cortisol release

TSH

Thyroid-Stimulating Hormone

Stimulates thyroid hormone release

reticular formation

• Network of interconnected nuclei in the brainstem

• Acts as a relay and integrative center for vital autonomic functions

• Ascending Reticular Activating System (ARAS):

  • Regulates wakefulness, alertness, and sleep-wake transitions

• Descending pathways:

  • Modulate motor and sensory signals

  • Influence autonomic tone

• Connects with the hypothalamus to coordinate autonomic output

medulla oblongata

• Located in the brainstem; contains autonomic reflex centers

• Directly regulates vital autonomic functions:

  • Cardiovascular center:

    • Controls heart rate, blood pressure, vascular tone

  • Respiratory center:

    • Regulates breathing rate and depth

  • Centers for vomiting, coughing, sneezing, swallowing

• Nucleus of the Solitary Tract (NTS):

  • Integrates visceral afferent input (e.g. from baroreceptors) VAI like VAI MOODU (MEDU/MOODU (RIGERSA THIS IS A TAMIL MNEMONIC FOR ME TO REMEMBER IGNORE DIS)

  • Communicates with hypothalamus and reticular formation

cerebellum

• Coordinates voluntary motor activity

  • Posture, balance, speech, coordination

• Receives input from many CNS structures

• Indirectly influences autonomic functions:

  • Adjusts somatic-autonomic interactions

  • Example: helps regulate BP changes during postural shifts

• think of a princess called sara bella (cere-bellum)

• must be good at balancing, have good posture, talk to lots of ppl, coordinate with other princesses

• receive input from many members of the palace

• indirectly influences ppl (autnonmic functions)

• ADJUSTS SA interactions (sexual assault interactions) bc shes an activist for womens bodies

basal ganglia

• Group of subcortical (beneath cerebral cortex) nuclei

• Main roles:

  • Motor control

  • Motor learning (via habituation)

  • Habit formation

  • Emotional behavior

• Modulates autonomic tone indirectly:

  • Via interactions with the limbic system and hypothalamus

  • Plays a role in stress-related responses and addictive behaviors

basal ganglia is the one that stops stress

basal = basil → interacts with L and H (lemon and herbs (and basil) LIMBIC AND HYPOTHALAMUS) → modulates flavour of the dish) (modulates the autonomic tone)

and basil is calming, so plays role in stress related response

cerebral cortex

• Contains specialized functional areas:

  • Frontal lobe: motor control, decision-making, speech

  • Parietal lobe: sensory perception, proprioception (orientation)

  • Temporal lobe: hearing, language comprehension

  • Occipital lobe: vision

• (for real, please turn over) (movie star, HV)

• Autonomic modulation via:

  • Prefrontal cortex: emotional regulation of autonomic activity

  • Insular cortex: integration of visceral sensations and autonomic output

INTEGRATION OF CNS IN THE “ALARM” OR “STRESS” RESPONSE

1. Definition and Purpose

• Stress = internal or external condition disrupting homeostasis

• Alarm phase = body’s initial response to stress

• Triggered via activation of the sympathetic nervous system

Neural and hormonal Parkways

• Amygdala: (small structure in the brain that processes emotions)

  • Activated by fear, anxiety, or emotional stress

  • Signals the hypothalamus

• Hypothalamus:

  • Stimulates the sympathetic nervous system

  • Signals the adrenal medulla:

    • Releases adrenaline and noradrenaline into bloodstream

  • Activates HPA axis:

    • Releases CRH → ACTH → adrenal cortex → cortisol

• Effects of sympathetic activation:

  • ↑ Heart rate & blood pressure

  • ↑ Blood flow to skeletal muscles

  • ↑ Glucose release (glycogenolysis)

  • ↑ Metabolic rate

  • ↑ Mental alertness