Central Luzon is the social center of The Country . Easily 30% of the nation's popula-tion live here. And the actual central urban area not only contains the 7.9 million people (May 1990) of Metro Manila with its 4 cities and 13 munici-palities but stretches beyond the capital's boundary to the north, the south and the east.

In the north beyond the border of Metro Manila are the towns of Meycauayan, Bocaue and Malolos, each with around 100,000 inhabitants. To the south are Cavite City, Bacoor and Imus, with no visible boundary to Las Piñas, the southernmost part of Metro Manila. And to the east are the towns of Cainta, Antipolo, and Taytay.

Anyone who wants to explain central Luzon mostly has to talk about Metro Manila. This book contains an exten-sive chapter on the national capital before this chapter on Central Luzon. Therefore, in these paragraphs we only deal with central Luzon excluding Manila.

To the north of Metro Manila lie the central Luzon plains constituting parts of the provinces of Bulacan, Pampanga, Tarlac, Nueva Ecija, and Pangasinan. The area is known as the rice bowl of the Philippines, as indeed, a large share of The Country 's rice is grown there. Tarlac province also produces a lot of sugar on Hacienda Luisita, owned by the family of former President Corazon Aquino. It is one of the biggest haciendas in the archipelago. Other crops of the plains north of Manila are corn and tobacco.

To the south of Metro Manila lie the provinces of Cavite, Laguna and Batangas which also have fertile soil; however, the terrain is not as advantageous for rice as it is hilly and even partially mountainous. Principal crops there are sugar and coconuts.

To the east of the capital, only the shore-line of Laguna de Bay is densely populated. What lies beyond are the not very inviting mountains of the Sierra Madre that do not allow much agricultural or other economic activity.

A volcano, Mt Pinatubo, dormant for over 600 years began erupting June 9, 1991, and has altered the landscape and geographical features of the plains of Central Luzon, especially of those provinces nearest the volcano - Zambales, Pampanga and Tarlac. Rivers have changed their courses and overflowed their banks clogged with volcanic debris having the consistency and appearance of wet cement. Vast agricultural lands were turned into a virtual wasteland of mud and ashes. The volcanic materials are acidic and most lands are covered with mud and ash too deep for it to be plowed under. The coral in surrounding waters has been silted and dying and the fish population has rapidly decreased. Smaller trees, brush and forage for animals began dying under the load of volcanic ash.

Whole villages have been swept away by the mud flows caused by rain on volcanic materials and people displaced number in the hundreds of thousands.

Expert volcanologists of the Philippines headed by Raymundo Punongbayan estimate that Mt Pinatubo emitted two cubic kilometers of volcanic debris including rock, sand, ash and other materials in the first eruptions after June 9, 1991.

Engineer Fortunato Dejoras, chief of the Philippine Office of Civil Defense (OCD), expressed fear that a large part of Luzon's useful land will turn into a vast desert. (See entries below for more information on the eruptions of Mt. Pinatubo.)

Of course, with the national capital in its midst, central Luzon has always been the po-litically decisive part of the islands. Apart from events taking place in the capital, a number of central Luzon towns have figured prominently in Philippine history.

In Malolos, Bulacan, the first constitution of an independent Philippines was promulgated January 21, 1899.

The town of Tarlac was the seat of a Philippine government for one month, March 1899, after President Aguinaldo had fled from Bulacan because of the approaching forces of the new colonial master, the US.

In Cavite province, many revolutionary events took place at the turn of the century. It started January 20, 1872 when in Cavite City some 200 Filipino soldiers mutinied and killed their officers. The event is known as the Cavite Conspiracy which led to the execution of three martyr priests, Jose Burgos, Mariano Gomez and Jacinto Zamora February 17, 1872.

Again 13 persons were executed in Cavite City September 12, 1896, as a retaliatory act of the Spanish for the Katipunan revolution of the same year. In memoriam of this execution, the capital town of Cavite Province was named Trece Martires. On June 12, 1898, the Philippines declared itself independent of Spain in Kawit, Cavite.

The east coast of central Luzon, administratively part of Quezon and Aurora provinces, is considered grossly neglected by the national gov-ernment and presumed under NPA control. On June 30, 1986, the NPA dared to permit full media coverage of an ambush of a government convoy near the town of Gumaca. The ambush left 21 soldiers dead.

On the mountainous peninsula of Bataan, the NPA is also considered strong. The communists had chosen the town of Samal in this province to stage its own armed parade December 14, 1986, the day a 3-month ceasefire between the government military and the NPA became effective. Several thousand armed rebels had gathered for that event. In Bataan province, the CPP and NPA also established their first local and regional alternative government bodies.

Bataan has a military tradition. The peninsula was chosen by US and Philippine troops in World War II as the last bastion of defense against the Japanese invasion forces. The US and Philippine forces only surrendered after heavy fighting on April 9, 1942.

It was followed by the infamous Death March of 36,000 US and Philippine soldiers from the town of Mariveles in Bataan province to Camp O'Donnel in the town of Capas in Tarlac province. It was a painful trek without food or water which many of the prisoners of war did not survive.

Capas, some 25 years later, on March 19. 1969, was the site for the founding of the New People's Army. From there, the NPA had extended its influence over the plains of central Luzon. This region had long been a hotbed for rebellions. In the 1950's the populist communist Huks had their stronghold in the central Luzon plains, mainly the province of Pampanga. Pampanga province also had been the site of several early revolts, in 1660 of Filipino natives against the Spanish, in 1762 of the Chinese against the Spanish and Philippine natives.

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The objective of the present review is to propose that dysfunctions in the central serotonergic system might be involved in the neurobiology of these 'sinful' behaviour patterns.